Pump Assembly Having an Axial-Flux Electric Drive

Abstract

The invention relates to a pump assembly, at least comprising a first housing, in which at least one first drive means for conveying a fluid is rotatably mounted, wherein a first drive shaft of the first drive means extends at least through a first side wall of the first housing in an axial direction; wherein, outside of the first housing, at least one first rotor of a first axial-flux electric drive is arranged on the first drive shaft, wherein the first axial-flux electric drive has only one stator.

Claims

1. A pump arrangement comprising a first housing in which there is arranged in a rotatably mounted manner a first drive for delivering a fluid, wherein a first drive shaft of the first drive extends through a first side wall of the first housing along an axial direction, wherein, outside the first housing, a first rotor of a first axial flux electric drive is arranged on the first drive shaft, wherein the first axial flux electric drive has only one stator.

2. The pump arrangement as claimed in claim 1, wherein, outside the first housing, the first drive shaft is not mounted or is mounted by way of a bearing, which exclusively accommodates forces acting in the axial direction.

3. The pump arrangement as claimed in claim 1, wherein the first axial flux electric drive is arranged in a second housing which connectable in a repeatably detachable manner to the first housing.

4. The pump arrangement as claimed in claim 1, wherein the first rotor is arranged directly adjacent to the first side wall and between the first side wall and a stator of the first axial flux electric drive.

5. The pump arrangement as claimed in claim 1, wherein the stator is arranged directly adjacent to the first side wall and between the first side wall and the first rotor.

6. The pump arrangement as claimed in claim 5, wherein the stator is arranged outside the first drive in a radial direction.

7. The pump arrangement as claimed in claim 6, wherein the stator is arranged so as to overlap the first housing along the axial direction.

8. The pump arrangement as claimed in claim 7, wherein the stator is arranged so as to overlap the first drive along the axial direction.

9. The pump arrangement as claimed in claim 5, wherein the stator is inseparably connected to the first side wall.

10. The pump arrangement as claimed in claim 1, wherein the first drive is a first gearwheel rotor.

11. The pump arrangement as claimed in claim 1, wherein the stator of the axial flux electric drive comprises materials which comprise soft magnetic composite.

12. The pump arrangement as claimed in claim 1, wherein the first axial flux electric drive forms a heating element which is connected in a heat-conducting manner to the first side wall via a heat-conducting structure.

13. The pump arrangement as claimed in claim 1, wherein a second axial flux electric drive is arranged outside the first housing and on a second side wall, opposite the first side wall, of the first housing, wherein the second axial flux electric drive is connected in a torque-transmitting manner either to the first drive shaft or to a second drive shaft of a second drive which is arranged in the first housing.

14. The pump arrangement as claimed in claim 13, wherein the second axial flux electric drive is connected in a torque-transmitting manner to the second drive shaft, and wherein the second drive is a second gearwheel rotor which is arranged so as to mesh with the first gearwheel rotor for delivering the fluid, wherein the two gearwheel rotors are arranged so as to be braced with respect to one another via the two axial flux electric drives.

15. The use of the pump arrangement as claimed in claim 1, for delivering a water-urea solution in a motor vehicle.

Description

[0040] The invention and the technical field will be explained in more detail below on the basis of the figures. It is to be noted that the invention is not intended to be limited by the exemplary embodiments shown. In particular, unless explicitly stated otherwise, it is also possible to extract partial aspects of the explanatory substantive matter in the figures and to combine these with other parts and findings from the present description including figures. The same reference signs are used to denote identical objects, and so, if appropriate, explanations from other figures may be used in a supplementary manner. In the drawings:

[0041] FIG. 1 schematically shows an exploded illustration of a first pump arrangement in a perspective view;

[0042] FIG. 2 schematically shows the exploded illustration of the first pump arrangement as per FIG. 1 in a side view in section;

[0043] FIG. 3 schematically shows the first pump arrangement as per FIGS. 1 and 2 in a side view in section;

[0044] FIG. 4 schematically shows the first pump arrangement as per FIG. 3 in a plan view;

[0045] FIG. 5 schematically shows an exploded illustration of a second pump arrangement in a perspective view;

[0046] FIG. 6 schematically shows the exploded illustration of the second pump arrangement as per FIG. 5 in a side view in section;

[0047] FIG. 7 schematically shows the second pump arrangement as per FIGS. 5 and 6 in a side view in section;

[0048] FIG. 8 schematically shows a third pump arrangement in a side view;

[0049] FIG. 9 schematically shows a fourth pump arrangement in a side view;

[0050] FIG. 10 schematically shows a fifth pump arrangement in a side view; and

[0051] FIG. 11 schematically shows a sixth pump arrangement in a side view.

[0052] FIG. 1 shows an exploded illustration of a first pump arrangement 1 in a perspective view. FIG. 2 shows the exploded illustration of the first pump arrangement 1 as per FIG. 1 in a side view in section. FIG. 3 shows the first pump arrangement 1 as per FIGS. 1 and 2 in a side view in section, and FIG. 4 shows the first pump arrangement 1 as per FIG. 3 in a plan view. FIGS. 1 to 4 will be described jointly below. Feed and discharge lines for the fluid 4 and electrical components (control unit, electrical connections, etc.) are not shown here since the arrangement thereof is normally known to a person skilled in the art.

[0053] The pump arrangement 1 comprises a first housing 2, which has a first side wall 6 and a receptacle 10 for the drive means 3, 21 (two intermeshing gearwheel rotors in this case). The drive means 3, 21 are arranged in a rotatably mounted manner in the first housing 2 for delivering a fluid 4, wherein a first drive shaft 5 of the first drive means 3 extends through the first side wall 6 of the first housing 2 along an axial direction 7. Outside the first housing 2, a first rotor 8 of a first axial flux electric drive 9 is arranged on the first drive shaft 5.

[0054] The first housing 2 encloses the drive means 3, 21 in particular in a vapor-tight and liquid-tight manner, wherein connections for feeding and discharging the fluid 4 to be delivered are provided. The first drive shaft 5 extends through a first side wall 6 of the first housing 2, wherein also here, liquid-tight sealing between the first side wall 6 and the first drive shaft 5 is provided. The first axial flux electric drive 9 comprises a (first) stator 13 and a first rotor 8, which are arranged coaxially with respect to one another. The coils 15 of the stator 13 interact with magnets 22 of the first rotor 8 to generate a torque for driving the first rotor 8, and thus the first drive shaft 5, in the circumferential direction 16. The stator 13 has a plurality of coils 15 which are arranged uniformly spaced apart from one another in a circumferential direction 16 on a return plate of the stator 13.

[0055] The first drive shaft 5 is mounted via radial bearings (which accommodate forces in the radial direction 24) and, if appropriate, axial bearings (which accommodate forces in the axial direction 7) only within the first housing 2. Outside the first housing 2, the first drive shaft 5 is arranged in a non-mounted manner.

[0056] The first axial flux electric drive 9 is arranged in a second housing 12 which is able to be connected in a repeatably detachable manner to the first housing 2. In this way, the first axial flux electric drive 9 is arranged so as to be protected with respect to the fluid 4 to be delivered, wherein the individual components of the pump arrangement 1 are replaceable, and/or to be maintained, independently of one another.

[0057] Here, the first rotor 8 is arranged directly adjacent to the first side wall 6 and between the first side wall 6 and the stator 13 of the first axial flux electric drive 9. With this arrangement, the first drive shaft 5 can be of very short form since the first rotor 8, which is connected to the first drive shaft 5, is arranged directly adjacent to the first face wall 6, through which the first drive shaft 5 extends into the second housing 12 from the first housing 2.

[0058] The stator 13 comprises a soft magnetic material 17, for example a so-called soft magnetic composite (SMC), or a combination of electric sheet steels and SMC.

[0059] FIGS. 5 to 7 show a second pump arrangement 1. FIG. 5 shows an exploded illustration of a second pump arrangement 1 in a perspective view. FIG. 6 shows the exploded illustration of the second pump arrangement 1 as per FIG. 5 in a side view in section. FIG. 7 shows the second pump arrangement 1 as per FIGS. 5 and 6 in a side view in section.

[0060] Reference is made to the embodiments relating to FIGS. 1 to 4. Here, by contrast to the first pump arrangement 1, the first rotor 8 and the stator 13 are arranged the other way round. Here, the stator 13 of the first axial flux electric drive 9 is arranged directly adjacent to the first side wall 6 and between the first side wall 6 and the first rotor 8. Here, the first drive shaft 5 is to be of longer form since it extends to the first rotor 8 also through the stator 13.

[0061] Here, as a heating element 25 of the first housing 2, use may be made of the stator 13 with its coils 15. The heat generation arising there may, for example, be introduced in a conductive manner into the first housing 2 via the first side wall 6. For this purpose, the power electronics allow for example a corresponding current to be provided, which flows through the coils 15 of the stator poles of the stator 13. In order to provide good heat transfer, the stator 13 is, with its rear surface, fully connected to the first housing 2, and thus to the first side wall 6 here.

[0062] The first side wall 6 forms at least a part of a fluid 4-conducting channel (in the region of the first drive means 3 and of the second drive means 21). In this case, at least a part of the first side wall 6 makes contact with the delivered fluid 4 in the region of the channel (for example in the region of the drive means 3, 21). Here, a heat-conducting structure 26 is formed only in this part-region, with the result that the heat generated in the region of the stator 15 can be released in a targeted manner to the fluid 4 via the heat-conducting structure 26.

[0063] FIG. 8 shows a third pump arrangement 1 in a side view. Reference is made to the embodiments relating to FIGS. 1 to 7. Here, by contrast to the first and second pump arrangement 1, a second axial flux electric drive 18 is arranged outside the first housing 2 in a third housing 23 and on a second side wall 19, opposite the first side wall 6, of the first housing 2. The second axial flux electric drive 18 is connected in a torque-transmitting manner to a second drive shaft 20 of the second drive means 21, which means is arranged in the first housing 2, wherein the second drive means 21 is a second gearwheel rotor which is arranged so as to mesh with the first gearwheel rotor for delivering the fluid 4.

[0064] FIG. 9 shows a fourth pump arrangement 1 in a side view. Reference is made to the embodiments relating to FIG. 8. By contrast to the third pump arrangement 1, the second axial flux electric drive 18 is connected in a torque-transmitting manner to the first drive shaft 5.

[0065] FIG. 10 shows a fifth pump arrangement 1 in a side view. Reference is made to the embodiments relating to FIGS. 5 to 7. By contrast to FIGS. 5 to 7, the stator 13 (that is to say its components coils 15, cores and return ring 14) is arranged outside the at least one first drive means 3 in a radial direction 24. In this case, the stator 13 (that is to say at least one of the components of coils 15, cores and return ring 14) is arranged so as to overlap the first housing 2, in this case so as to overlap at least one bearing 11 (radial bearing, axial bearing, slide bearing, friction bearing) of the first drive shaft 5 and so as to overlap the at least one first drive means 3, along the axial direction 7. This preferred embodiment allows a particularly compact construction of the pump arrangement 1, wherein (exclusively) the at least one first drive means 3, the first side wall 6 (with the bearing 11 for example as a constituent part of the first side wall 6) and the first rotor 8 are arranged next to one another along the axial direction 7 and thus determine the structural size of the pump arrangement 1 along the axial direction 7.

[0066] FIG. 11 shows a sixth pump arrangement 1 in a side view. Reference is made to the embodiments relating to FIGS. 1 to 4. Here, by contrast to the first pump arrangement 1, the first drive shaft 5 is arranged so as to be mounted by way of a bearing 11 outside the first housing 2, wherein the bearing 11 exclusively accommodates forces acting in the axial direction 7. It is thus the case here that no radial bearing, that is to say a bearing 11 which serves for providing support with respect to forces acting in the radial direction 24, is arranged outside the first housing 2. Also here, the first drive shaft 5 is exclusively mounted in the first housing 2, with the result that there is no requirement for the structural space for bearings 11, which are otherwise needed, outside the first housing 2. In this way, a particularly compact design of the pump arrangement 1 is possible.

LIST OF REFERENCE SIGNS

[0067] 1 Pump arrangement [0068] 2 First housing [0069] 3 First drive means [0070] 4 Fluid [0071] 5 First drive shaft [0072] 6 First side wall [0073] 7 Axial direction [0074] 8 First rotor [0075] 9 First axial flux electric drive [0076] 10 Receptacle [0077] 11 Bearing [0078] 12 Second housing [0079] 13 Stator [0080] 14 Return ring [0081] 15 Coil [0082] 16 Circumferential direction [0083] 17 Material [0084] 18 Second axial flux electric drive [0085] 19 Second side wall [0086] 20 Second drive shaft [0087] 21 Second drive means [0088] 22 Magnet [0089] 23 Third housing [0090] 24 Radial direction [0091] 25 Heating element [0092] 26 Heat-conducting structure