LIQUID PUMP

Abstract

A fluid pump for conveying a fluid may include an internal rotor rotatable about an axis of rotation relative to an external stator and an impeller connected to the internal rotor in a rotationally fixed manner configured to convey a fluid. The internal rotor may include a rotor receiving sleeve having a base body. The base body may include a receiving chamber configured to receive an anchor unit. The internal rotor may further include a bearing bushing penetrating the rotor receiving sleeve coaxially to the axis of rotation. The bearing bushing may be configured to receive a rotor shaft. The impeller may be directly connected to the rotor receiving sleeve in a rotationally fixed manner.

Claims

1. A fluid pump for conveying a fluid, comprising: an internal rotor about an axis of rotation relative to an external stator; an impeller connected to the internal rotor in a rotationally fixed manner for conveying a fluid; the internal rotor including a rotor receiving sleeve, the rotor receiving sleeve including a base body having a receiving chamber configured to receive an anchor unit; the internal rotor further including a bearing bushing structured and arranged to penetrate the rotor receiving sleeve coaxially to the axis of rotation, the bearing bushing configured to receive a rotor shaft; wherein the impeller is directly connected to the rotor receiving sleeve in a rotationally fixed manner.

2. The fluid pump according to claim 1, wherein the receiving chamber is closable by a cover, and the cover is a separate component from the impeller.

3. The fluid pump according to claim 2, wherein the impeller is directly connected to the base body in a rotationally fixed manner.

4. The fluid pump according to claim 1, wherein the receiving chamber is closable by a cover and the impeller is directly connected to the cover in a rotationally fixed manner.

5. The fluid pump according to claim 4, wherein the impeller and the cover are integrally provided as a single piece.

6. The fluid pump according to claim 1, wherein the receiving chamber is annular and is defined radially on an inside by a cylindrical inner wall of the base body and radially on an outside by a cylindrical outer wall of the base body.

7. The fluid pump according to claim 6, wherein the base body has an axial end facing away from the impeller, the axial end including a bottom connecting the inner wall of the base body and the outer wall of the base body.

8. The fluid pump according to claim 7, wherein the base body, the inner wall of the base body, the outer wall of the base body, and the bottom are integrally provided as a single piece.

9. The fluid pump according to claim 6, wherein the impeller is coupled to the inner wall of the base body via an internal welded connection and to the outer wall of the base body via an external welded connection.

10. The fluid pump according to claim 9, wherein the internal welded connection and the external welded connection fluidicially seal the receiving chamber.

11. The fluid pump according to claim 1, wherein the impeller is directly connected in a rotationally fixed manner to an impeller holder disposed on the base body.

12. The fluid pump according to claim 11, wherein the impeller holder is integrally molded on the base body.

13. The fluid pump according to claim 1, further comprising two bearing sleeves arranged axially spaced apart from one another and configured to receive the rotor shaft, the two bearing sleeves arranged such that an annular chamber is defined radially between the bearing bushing and the rotor shaft when the rotor shaft is received within the bearing bushing and the two bearing sleeves.

14. The fluid pump according to claim 13, wherein the two bearing sleeves are arranged on opposing longitudinal ends of the bearing bushing.

15. The fluid pump according to claim 13, wherein a first bearing sleeve of the two bearing sleeves is arranged on a longitudinal end of the bearing bushing facing away from the impeller and a second bearing sleeve of the two bearing sleeves is arranged in the impeller at an axial distance from the bearing bushing.

16. The fluid pump according to claim 1, wherein the rotor receiving sleeve at least one of: at least partially radially encloses the bearing bushing at least on an outer jacket surface thereof; at least partially axially engages around the bearing bushing.

17. The fluid pump according to claim 1, wherein: the rotor receiving sleeve is a plastic injection molded part; the rotor receiving sleeve is secured via direct injection onto the bearing bushing; and the rotor receiving sleeve and the bearing bushing are operatively connected via at least one of a positive connection and a frictional connection.

18. The fluid pump according to claim 11, wherein the impeller holder includes an annular collar on a side, facing the impeller.

19. The fluid pump according to claim 11, wherein the impeller includes an annular web on a side of the impeller facing the impeller holder, the annular web enclosed by two radially spaced apart annular grooves and configured to support an annular collar of the impeller holder.

20. The fluid pump according to claim 19, wherein the impeller has a support surface on a side facing away from the annular web, the support surface having a diameter that is equal to or larger than a diameter of the annular web.

21. The fluid pump according claim 1, wherein the rotor receiving sleeve, on a side facing away from the impeller, includes at least two positioning noses, the at least two positioning noses arranged offset by 180 in a circumferential direction of the axis of rotation and disposed radially outside of the bearing bushing.

22. The fluid pump according to claim 1, wherein the impeller includes a passage opening concentric to the bearing bushing.

23. The fluid pump according to claim 1, wherein the impeller and the rotor receiving sleeve are composed of the same material.

24. The fluid pump according to claim 1, wherein the rotor receiving sleeve is connected to the impeller via at least one of ultrasonic welding, rotational friction welding, and laser beam welding.

25. The fluid pump according to claim 1, wherein the impeller is adhered to the rotor receiving sleeve.

26. The fluid pump according to claim 1, wherein the impeller is connected to the rotor receiving sleeve via a positive connection.

27. A method for installing an impeller on a rotor of an electric motor, comprising: positioning an internal rotor relative to an external stator via at least two positioning noses arranged offset from one another by 180 in a circumferential direction of a rotation axis of the internal rotor and clamping the internal rotor in place, the internal rotor including a rotor receiving sleeve and a bearing bushing, the rotor receiving sleeve including a base body having a receiving chamber configured to receive an anchor unit, wherein positioning the internal rotor includes arranging the bearing bushing so as to penetrate the rotor receiving sleeve coaxially to the rotation axis for receiving a rotor shaft attaching an impeller to the internal rotor on a side opposite the at least two positioning noses and ultrasonically welding between the impeller and the rotor receiving sleeve to connect the impeller to the internal rotor; and monitoring the ultrasonic welding by measuring at least one of a force level and a displacement level.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In each case schematically,

[0036] FIG. 1 shows a sectional illustration of the fluid pump according to the invention comprising an impeller arranged on a rotor receiving sleeve of a rotor,

[0037] FIG. 2 shows a sectional illustration of the rotor, wherein the rotor receiving sleeve is injected onto a bearing bushing,

[0038] FIG. 3 shows a sectional illustration of the impeller comprising a concentric passage opening,

[0039] FIG. 4 shows an isometric view of the fluid pump from a side, which faces away from the impeller,

[0040] FIG. 5 shows a sectional illustration of the rotor with arranged impeller and a schematically suggested sonotrode,

[0041] FIG. 6 shows a sectional illustration of the fluid pump as in FIG. 1, but in a different embodiment.

DETAILED DESCRIPTION

[0042] FIGS. 1 and 6 in each case show a sectional illustration of a fluid pump 1, in particular for a motor vehicle 2, which is otherwise not shown, which is formed at least of a non-illustrated electric motor 23 and an impeller 13 arranged thereon, for conveying a fluid 10. As is well-known, such an electric motor 23 can have an external stator 4, which is not illustrated in detail, and an internal rotor 3. The rotor 3 is supported so as to be capable of being rotated about an axis of rotation 5 relative to the stator 4 and comprises at least one rotor receiving sleeve 7. The rotor receiving sleeve 7 has a base body 24 comprising a receiving chamber 25 for receiving an anchor unit 8, and according to the embodiment shown in FIG. 1, a cover 9 for closing the receiving chamber 25. According to the embodiment shown in FIG. 6, this cover 9 is integrated into the impeller 13 or is formed by the impeller 13 itself, respectively, so that the impeller 13 quasi has a cover section 9. The anchor unit 8 can for example have a laminated core and permanent magnets arranged on this laminated core. The cover 9 or the cover section 9, respectively, can hermetically seal the receiving chamber 25 and can thus protect such an anchor unit 8, which is arranged in the receiving chamber 25, against such a fluid 10. The rotor 3 further has a bearing bushing 11, which is provided to receive a rotor shaft 6 and which penetrates the rotor receiving sleeve 7 of the rotor 3 coaxially to the axis of rotation 5. According to the embodiment shown in FIG. 1, the rotor shaft 6 can be radially pressed with bearing sleeves 12a and 12b, which are in each case inserted on the longitudinal ends of the bearing bushing 11. The impeller 13 is connected to the rotor 3 in a rotationally fixed manner.

[0043] FIG. 2 shows a sectional illustration of the rotor 3, in which the rotor receiving sleeve 7 is injected onto a bearing bushing 11. It is important to note that the base body 24 of the rotor receiving sleeve 7 can substantially be meant when referring to an injection onto or an encasement of the rotor receiving sleeve 7 on such a bearing bushing 11 or on such a bearing sleeve 12a, 12b. According to FIG. 1, the bearing bushing 11 can in each case have such a bearing sleeve 12a, 12b on the longitudinal ends thereof, which is provided for receiving the rotor shaft 6 and with which the rotor shaft 6 can be pressed together radially. The rotor shaft 6, the bearing sleeves 12a, 12b and the bearing bushing 11 are connected to one another in a rotationally fixed manner. The rotor receiving sleeve 7 can at least partially radially enclose the bearing bushing 11 and in particular the bearing sleeves 12a, 12b, which are arranged on the bearing bushing 11, at least on the outer jacket surface thereof. The rotor receiving sleeve 7 can further at least partially axially engage around the bearing bushing 11 and in particular the bearing sleeves 12a, 12b, which are arranged on the bearing bushing 11. The rotor receiving sleeve 7 can be embodied as plastic injection molded part and can be directly injected onto the bearing bushing 11. In addition, the rotor receiving sleeve 7 and the bearing bushing 11 can advantageously be in a positive and/or frictional operative connection with one another. An impeller holder 14 can be arranged on a side of the rotor receiving sleeve 7, which faces an impeller 13, which is to be attached subsequently. The impeller holder 14 is preferably integrally molded on the rotor receiving sleeve 7. The impeller holder 14 of the rotor receiving sleeve 7 can have an annular collar 15 on a side, which faces the impeller 13. In the annular receiving chamber 25, the rotor receiving sleeve 7 can have the anchor unit 8 and can be hermetically sealed by means of such a cover 9 or cover section 9, respectively. The separate cover 9 can be connected to the rotor receiving sleeve 7 by means of ultrasonic welding, rotational friction welding or laser beam welding. The separate cover 9 can further be adhered to the rotor receiving sleeve 7 or can be pressed together with it.

[0044] FIG. 3 shows a sectional illustration of the impeller 13 of a fluid pump 1 according to FIG. 1. On a side facing the impeller holder 14 of the rotor receiving sleeve 7, the impeller 13 can have an annular web 16, which is enclosed by two radially spaced apart annular grooves 17. The annular collar 15, which is not shown here, of the impeller holder 14 of the rotor receiving sleeve 7 can support itself on the annular web 16. On a side facing away from the annular web 16, the impeller 13 can furthermore have a support surface 18, which can for example be provided for receiving a sonotrode 19. The diameter of the support surface 18 advantageously corresponds at least to the diameter of the annular web 16 of the impeller 13 or at least to a diameter, respectively, which assumes an area of the operative connection between the impeller 13 and the rotor receiving sleeve 7. The impeller 13 can have a concentric passage opening 22 to the bearing bushing 11 of the rotor 3.

[0045] FIG. 4 shows an isometric view of the fluid pump 1 on an axial side, which faces away from the impeller 13. On a side, which faces away from the impeller 13, the rotor 3, in particular the rotor receiving sleeve 7, can have at least two positioning noses 20, which are arranged so as to be shifted for example by 180 in the circumferential direction 21 and which are arranged at least radially outside of the bearing bushing 11. The positioning noses 20 protrude at least partially axially from the rotor receiving sleeve 7.

[0046] FIG. 5 shows a sectional illustration of the rotor 3 with arranged impeller 13 and a schematically suggested sonotrode 19, which is mentioned further above. The impeller 13 and preferably the area of the impeller holder 14 of the rotor receiving sleeve 7 can preferably be made of an identical material, in particular of a plastic. A desired rotationally fixed operative connection between the impeller holder 14 on the rotor receiving sleeve 7 and the impeller 13 can be established by means of ultrasonic welding, rotational friction welding or laser beam welding. The impeller 13 can further be adhered to the impeller holder 14 of the rotor receiving sleeve 7. In addition, the operative connection between the impeller 13 and the rotor 3, in particular the rotor receiving sleeve 7, can be established by means of a positive connection, which is brought about in particular by means of a clipping or a pressing together.

[0047] As mentioned, the receiving chamber 25 in the base body 24 is advantageously open on an axial side, which faces the impeller 13, so that the anchor unit 8 can be inserted axially on this axial side. To seal with respect to the conveyed fluid 10, the receiving space 25 is closed in the assembled state of the rotor 3. For this purpose, said cover 9 can be used, which is a separate component with respect to the impeller 13 and with respect to the base body 24.

[0048] In a non-illustrated embodiment, provision can be made for the impeller 13 to be directly connected to the separate cover 9 in a rotationally fixed manner, which cover, in turn, is connected to the base body 24 in a rotationally fixed manner.

[0049] FIG. 6 now shows an embodiment, in which the impeller 13 and the cover 9 are embodied in one piece. In other words, the cover 9 is integrally molded on the impeller 13 in this case. This is also synonymous with the fact that the impeller 13 simultaneously forms the cover as additional function. As a result, the impeller 13 has said cover section 9. In FIG. 6, the impeller 13 or the cover section 9 thereof, respectively, thus closes the receiving chamber 25 of the rotor receiving sleeve 7.

[0050] According to FIGS. 1, 2, 5 and 6, the receiving chamber 25 is embodied annularly and is defined by a cylindrical inner wall 26 of the base body 24 radially on the inside and by a cylindrical outer wall 27 of the base body 24 radially on the outside. The anchor unit 8 thus does not have any contact with the bearing bushing 11.

[0051] On its axial end, which faces away from the impeller 13, the base body 24 preferably has a bottom 28, which connects the inner wall 26 to the outer wall 27. This means that the receiving chamber 25 of the base body 24 is open on the axial side facing the impeller 13, so that the anchor unit 8 can be inserted on this axial side. Provision can preferably also be made for the base body 24 comprising the inner wall 26, the outer wall 27, and the bottom 28, to be produced in one piece. The base body 24 comprising inner wall 26, outer wall 27 and bottom 28 is thus also produced monolithically, e.g. as injection molded part. The above-mentioned positioning noses 20 can be integrally molded on this bottom 28.

[0052] According to Fig., the impeller 13, which forms the cover 9 or which has the cover section 9, respectively, can be fastened to the inner wall 26 by means of an internal welded connection 30 and to the outer wall 27 by means of an external welded connection 31. The external welded connection 31 seals the receiving chamber 25 to the outside with respect to the fluid 10, which surrounds the rotor 3. The internal welded connection 30 also seals the receiving chamber 25 to the outside with respect to the fluid 10, which can enter into the chamber, which is enclosed by the inner wall 26, along the rotor shaft 6 past the bearing sleeves 12a, 12b.

[0053] According to the embodiments of FIGS. 1, 2, 5 and 6 shown here, provision can be made for the two bearing sleeves 12a, 12b, which are axially spaced apart from one another, for the improved integration of the rotor shaft 6 into the rotor 3. The two bearing sleeves 12a, 12b are thereby embodied and are adapted to the rotor shaft 6 and the bearing bushing 11 in such a way that an annular chamber 29 is formed radially between the bearing bushing 11 and the rotor shaft 6.

[0054] In the examples of FIGS. 1, 2 and 5, the two bearing sleeves 12a, 12b are arranged on the two longitudinal ends of the bearing bushing 11. In the example shown in FIG. 6, in contrast, provision is made for the one bearing sleeve 12a to be arranged on the bearing bushing 11 on a longitudinal end of the bearing bushing 11, which faces away from the impeller 13, while the other bearing bushing 12b is arranged in or on the impeller 13, respectively, axially spaced apart from the bearing bushing 11. The axial length of the rotor 3 comprising impeller 13 can thus be reduced.