PUMP-MOTOR UNIT COMPRISING AN INTEGRATIVE HOUSING COVER

Abstract

A pump-motor unit for delivering a fluid, for example gear oil and/or lubricating oil in motor vehicles, includes: a housing having a housing cover, an intermediate housing structure and a motor cover, wherein the housing cover and the intermediate housing structure define a delivery chamber axially on both end-facing sides and circumferentially in the radial direction; a delivery device featuring a delivery member, which can be rotated within the delivery chamber, for delivering the fluid; and a drive motor which is connected to the delivery device via a drive shaft, wherein the housing cover forms an accommodating well, and the drive motor and the intermediate housing structure are arranged in the accommodating well.

Claims

1.-15. (canceled)

16. A pump-motor unit for delivering a fluid, for example gear oil and/or lubricating oil in motor vehicles, comprising: a housing comprising a housing cover, an intermediate housing structure and a motor cover, wherein the housing cover and the intermediate housing structure define a delivery chamber axially on both end-facing sides and circumferentially in the radial direction; a delivery device featuring a delivery member, which can be rotated within the delivery chamber, for delivering the fluid; and a drive motor which is connected to the delivery device via a drive shaft, wherein the housing cover forms an accommodating well, and the drive motor and the intermediate housing structure are arranged in the accommodating well.

17. The pump-motor unit according to claim 16, wherein the intermediate housing structure defines the delivery chamber axially on an end-facing side and circumferentially, and the housing cover defines the delivery chamber axially on an end-facing side.

18. The pump-motor unit according to claim 16, wherein the drive motor is arranged between the motor cover and the intermediate housing structure in the axial direction.

19. The pump-motor unit according to claim 16, wherein the drive motor is an electric motor comprising a rotor and a stator, and the rotor is non-rotationally connected to the drive shaft.

20. The pump-motor unit according to claim 16, wherein the delivery member is non-rotationally connected to the drive shaft.

21. The pump-motor unit according to claim 16, wherein a stator of the drive motor is held axially by the intermediate housing structure and the motor cover.

22. The pump-motor unit according to claim 16, wherein a radial gap is formed between a stator of the drive motor and the housing cover.

23. The pump-motor unit according to claim 16, wherein the motor cover seals off the accommodating well of the housing cover on the side which faces axially away from the delivery chamber.

24. The pump-motor unit according to claim 16, wherein the housing cover comprises a housing cover circumferential wall, and the motor cover comprises a motor cover circumferential wall, wherein the housing cover circumferential wall and the motor cover circumferential wall axially overlap each other, and wherein at least one gasket is formed between the motor cover and the housing cover, in order to seal off the accommodating well in a fluid-proof seal.

25. The pump-motor unit according to claim 16, wherein the motor cover protrudes in the axial direction at least partially into the accommodating well of the housing cover.

26. The pump-motor unit according to claim 16, wherein the accommodating well is connected in fluid communication with a suction port of the pump-motor unit via a connecting channel in the region of the drive motor, and the connecting channel is formed as a passage through the intermediate housing structure.

27. The pump-motor unit according to claim 16, wherein the housing cover and/or the intermediate housing structure mounts or jointly mount the drive shaft.

28. The pump-motor unit according to claim 16, wherein the pump-motor unit comprises an electronics cover which is arranged on the end-facing side on the side of the motor cover which faces axially away from the drive motor, and wherein an electronics space formed between the motor cover and the electronics cover is defined in the axial direction by the electronics cover and/or the motor cover, and control electronics are formed in the electronics space.

29. The pump-motor unit according to claim 28, wherein the electronics cover and/or the motor cover surrounds the control electronics on the radially outer side, and wherein at least one gasket is formed between the electronics cover and the motor cover, in order to seal off the electronics space in a fluid-proof seal.

30. The pump-motor unit according to claim 28, wherein the electronics cover comprises cooling fins for cooling the pump-motor unit.

31. The pump-motor unit according to claim 19, wherein the drive motor is an electric internal-rotor motor.

32. The pump-motor unit according to claim 19, wherein the rotor is non-rotationally connected to the drive shaft such that it is fixed against shifting in the axial direction.

33. The pump-motor unit according to claim 20, wherein the delivery member is non-rotationally connected to the drive shaft such that it is fixed against shifting in the axial direction.

34. The pump-motor unit according to claim 23, wherein the motor cover seals off the accommodating well of the housing cover in a fluid-proof seal, on the side which faces axially away from the delivery chamber.

35. The pump-motor unit according to claim 24, wherein the at least one gasket is a radial gasket.

36. The pump-motor unit according to claim 29, wherein the at least one gasket is a radial gasket.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0099] FIG. 1 a cross-section of the pump-motor unit along the drive shaft;

[0100] FIG. 2 a cross-section of the pump-motor unit through a second sectional plane;

[0101] FIG. 3 an isometric view of the pump-motor unit.

DETAILED DESCRIPTION OF THE INVENTION

[0102] FIGS. 1 and 2 each show a cross-section through the pump-motor unit along the drive shaft 4, wherein the sectional planes of the two figures are perpendicular to each other. The pump-motor unit comprises a housing featuring a housing cover 1, an intermediate housing structure 12 and a motor cover 2, wherein the housing cover 1 and the intermediate housing structure 12 define a delivery chamber axially on both end-facing sides and circumferentially in the radial direction. The pump-motor unit also comprises: a delivery device 10 featuring a delivery member 13, 14, which can be rotated within the delivery chamber, for delivering a fluid; and a drive motor 20 which is connected to the delivery device 10 via a drive shaft 4. The housing cover 1 and the intermediate housing structure 12 and the housing cover are formed by components which are formed separately from each other.

[0103] As shown in FIG. 1, the pump-motor unit comprises a fitting structure 40 which is formed by the housing cover 1. The fitting structure 40 protrudes radially from the housing cover circumferential wall and, as shown in FIG. 3, comprises passages 41 for fastening elements. When fitted in a fitting well of a gearbox, for example, the pump-motor unit can be fastened by means of the fitting structure 40. The pump-motor unit in accordance with an aspect of the invention is preferably an exterior pump-motor unit which is not designed to be accommodated in a fitting well and can for example be screwed onto a gearbox from the outside. The person skilled in the art will be aware of a multitude of ways of fitting and in particular fastening pump-motor units, such that this will not be discussed in further detail at this juncture. The pump-motor unit in accordance with an aspect of the invention need not then be fastened via fastening elements, but rather could for example also be glued or clamped via the fitting structure.

[0104] The housing cover 1 of the housing of the pump-motor unit is integrally formed. The housing cover 1 is preferably molded in an original-molding method or a reshaping method or consists of parts which are joined in a material fit. The housing cover 1 is preferably originally molded from metal. The housing cover 1 of the housing of the pump-motor unit comprises an accommodating well 11 in which the intermediate housing structure 12 is arranged. In this way, the housing cover 1 and in particular the accommodating well 11 of the housing cover 1 encloses the intermediate housing structure 12 on the radially outer side. The intermediate housing structure 12 is supported radially and axially in the accommodating well 11 of the housing cover 1, wherein an end-facing side of the intermediate housing structure 12 which faces the housing cover 1 is supported axially on the base of the accommodating well 11.

[0105] In addition to the intermediate housing structure 12, the drive motor 20 is also arranged in the accommodating well 11 of the housing cover 1, such that the accommodating well 11 also encloses the drive motor 20 on the radially outer side. The intermediate housing structure 12 is arranged between the housing cover 1 and the drive motor 20 in the axial direction.

[0106] The intermediate housing structure 12 and the housing cover 1 define the delivery chamber axially on both end-facing sides and circumferentially in the radial direction. The intermediate housing structure 12 defines the delivery chamber on a first end-facing side of the delivery chamber and circumferentially in the radial direction, and the housing cover 1 defines the delivery chamber on a second end-facing side. The intermediate housing structure 12 comprises a cavity in which the delivery chamber is formed and which defines the delivery chamber on the end-facing side and circumferentially.

[0107] The housing cover 1 forms a pressure port 5 and a suction port 6. Both the pressure port 5 and the suction port 6 are formed in the end-facing side of the housing cover 1 which faces axially away from the delivery chamber. The pressure port 5 is connected in fluid communication with a delivery chamber outlet, and the suction port 6 is connected in fluid communication with a delivery chamber inlet. The delivery chamber outlet and the delivery chamber inlet are formed in the housing cover 1 in the end-facing side of the housing cover 1 which axially faces the delivery chamber, preferably in the form of a pressure pocket and a suction pocket.

[0108] A recess groove 17 which encircles a rotational axis of the drive shaft 4 is formed between the intermediate housing structure 12 and the housing cover 1. The recess groove 17 is formed in the end-facing side of the intermediate housing structure 12 which axially faces the housing cover 1 and in the end-facing side of the housing cover 1 which axially faces the intermediate housing structure 12. The recess groove 17 formed in the intermediate housing structure 12 overlaps, preferably completely, in the radial direction with the recess groove 17 formed in the housing cover 1. The recess groove 17 in the intermediate housing structure 12 can extend in the radial direction not as far as or further than the recess groove 17 in the housing cover 1. The recess groove 17 in the intermediate housing structure 12 preferably extends in the radial direction about as far as the recess groove 17 in the housing cover 1. The recess groove 17 is preferably connected in fluid communication with the suction port 6 of the pump-motor unit. In addition to reducing weight, the recess groove 17 serves in particular to reduce cost when machining the end-facing side of the intermediate housing structure 12 which faces the housing cover 1 and the end-facing side of the housing cover 1 which faces the intermediate housing structure 12.

[0109] The delivery member 13, 14 is rotatably arranged in the delivery chamber. The delivery member 14 is formed by an externally toothed internal gear which is surrounded by a second delivery member 13 which is formed by an internally toothed gear. The rotational axis of the first delivery member 14 and the rotational axis of the second delivery member 13 extend parallel to each other at a distance. The delivery member 14 and the second delivery member 13, in particular the teeth of the externally toothed delivery member 4 and the teeth of the internally toothed second delivery member 13, are in engagement such that a rotation of the delivery member 14 is transmitted onto the second delivery member 13. Delivery cells are formed between the engaging teeth of the delivery member 14 and the second delivery member 13, which change their volume in the circumferential direction, such that fluid can be delivered from a low-pressure side of the pump to a high-pressure side of the pump. Internal gear pumps of this type are known to the person skilled in the art, for which reason a detailed description shall be omitted here. An aspect of the invention is not explicitly limited to internal gear pumps, and vane cell pumps or external gear pumps can for example also be used.

[0110] The delivery member 14 is non-rotationally connected to the drive shaft 4 and can also be connected to the drive shaft 4 such that it is fixed against shifting in the axial direction. Preferably, the delivery member 14 is non-rotationally connected to the drive shaft 4 and can be shifted on the drive shaft 4 in the axial direction. The delivery member 14 is rotary-driven by the drive shaft 4. The drive shaft 4 protrudes through both the delivery member 14 and the second delivery member 13 in the axial direction and protrudes from both the delivery member 14 and the second delivery member 13 on both sides in the axial direction.

[0111] The drive shaft 4 is mounted by the housing cover 1 and the intermediate housing structure 12, wherein the delivery member 14 is arranged between the bearing point of the housing cover 1 and the bearing point of the intermediate housing structure 12. The housing cover 1 and the intermediate housing structure 12 each form a slide bearing for the drive shaft 4.

[0112] The slide bearing of the intermediate housing structure 12 is connected in fluid communication with the delivery chamber via a leakage. The leakage is preferably created via a radial gap between the drive shaft 4 and the intermediate housing structure 12 in the region of the bearing point of the intermediate housing structure 12 for the drive shaft 4. The radial gap can surround the drive shaft 4 in the circumferential direction over a certain angle or over 360°. The slide bearing of the intermediate housing structure 12 is preferably connected in fluid communication with the high-pressure side of the delivery chamber, such that pressure fluid passes from the delivery chamber into the slide bearing of the intermediate housing structure 12. In preferred embodiments, the slide bearing of the housing cover 1 is also connected in fluid communication with the delivery chamber, particularly preferably with the high-pressure side of the delivery chamber.

[0113] The drive motor 20 of the pump-motor unit is an electric motor, in particular an electric internal-rotor motor, comprising a rotor 24 and a stator 23, wherein the rotor 24 is non-rotationally connected to the drive shaft 4, preferably such that it is fixed against shifting in the axial direction. The drive motor 20 is arranged in the accommodating well 11 of the housing cover 1. The stator 23 of the drive motor 20 is held axially by the intermediate housing structure 12 and the motor cover 2. A radial gap which is formed between the stator 23 and the housing cover 1 surrounds the stator over 360°.

[0114] The motor cover 2 seals off the accommodating well 11 of the housing cover 1, in a fluid-proof seal, on the side which faces axially away from the delivery chamber. To this end, the housing cover 1 comprises a housing cover circumferential wall, and the motor cover 2 comprises a motor cover circumferential wall, wherein the housing cover circumferential wall and the motor cover circumferential wall axially overlap each other and at least one gasket 25 is formed between the motor cover 2 and the housing cover 1. The motor cover 2 protrudes in the axial direction at least partially into the accommodating well 11 of the housing cover 1, such that the housing cover circumferential wall at least partially encloses the motor cover circumferential wall on the outside in the axial direction.

[0115] The drive motor 20 is preferably a wet-running electric motor. To this end, the accommodating well 11 of the housing cover 1 is connected in fluid communication with the delivery chamber in the region of the drive motor 20. The accommodating well 11 of the housing cover 1 is preferably connected in fluid communication with the high-pressure side of the delivery chamber in the region of the drive motor 20, in particular via the slide bearing of the intermediate housing structure 12.

[0116] In order that the fluid can flow off from the accommodating well 11 in the region of the drive motor 20, the accommodating well 11 is connected in fluid communication with the suction port 6 of the pump-motor unit via a connecting channel 16 in the region of the drive motor 20. The connecting channel 16 is formed as a passage through the intermediate housing structure 12. The accommodating well 11 is thus also connected in fluid communication with the delivery chamber inlet in the region of the drive motor 20. In this way, fluid which is situated in the region of the drive motor 20 can flow off from the accommodating well 11 via the connecting channel 16. Fluid from the delivery chamber thus continuously flows around and cools the drive motor 20.

[0117] The pump-motor unit also comprises an electronics cover 3 which is arranged on the end-facing side on the side of the motor cover 2 which faces axially away from the drive motor 20. An electronics space formed between the motor cover 2 and the electronics cover 3 is defined in the axial direction and in the circumferential direction by the electronics cover 3 and the motor cover 2, wherein the electronics cover 3 defines the electronics space circumferentially and on the end-facing side which faces axially away from the drive motor 20. The motor cover 2 defines the electronics space on the end-facing side which axially faces the drive motor 20.

[0118] The motor cover 2 seals off the electronics space, in a fluid-proof seal, on the end-facing side on the side which axially faces the drive motor 20. To this end, the motor cover circumferential wall overlaps in the axial direction with an electronics cover circumferential wall, wherein a gasket 35 is formed between the motor cover circumferential wall and the electronics cover circumferential wall. The gasket 35 is formed as a radial gasket. The motor cover 2 protrudes axially into a cavity in the electronics cover 3, such that the motor cover circumferential wall is enclosed on the radially outer side by the electronics cover circumferential wall.

[0119] The electronics cover 3 comprises cooling elements, in particular cooling fins, for cooling the pump-motor unit on the end-facing side which faces axially away from the drive motor 20. The cooling fins are preferably formed from metal. The electronics cover 3 and the cooling elements can be integrally formed together, for example molded in an original-molding method or a reshaping method, or can consist of parts which are joined in a material fit, for example by means of sintering. It is however also possible to join the cooling elements to the electronics cover 3 in a subsequent manufacturing step. The electronics cover 3 can then for example be formed from a different material to the cooling fins. Preferably, the electronics cover 3 and the cooling fins comprise the same material.

[0120] Control electronics 32 are formed in the electronics space. The control electronics 32 serve to control the drive motor 20. The control electronics 32 are surrounded on the radially outer side by the electronics cover 3. The rear side of the control electronics 32, which lies axially opposite the electronics cover 3, is connected to the electronics cover 3 in a thermally conductive way. The control electronics 32 are preferably connected to the electronics cover 3 in a thermally conductive way by means of a thermally conductive paste.

[0121] The housing cover 1 and/or the intermediate housing structure 12 are preferably manufactured from metal, but can for example also be manufactured from plastic. The motor cover 2 in particular is preferably manufactured from plastic, but can for example also be manufactured from metal.

[0122] FIG. 3 shows an isometric view of the pump-motor unit. The housing of the pump-motor unit is held together by means of holding elements 7, wherein the holding elements 7 are preferably formed by screws. The holding elements 7 protrude through the housing cover 1 and/or the electronics cover 3, wherein the motor cover 2 is held axially between the housing cover 1 and the electronics cover 3. The holding elements 7 can also protrude through the motor cover 2. Alternatively, the motor cover 2 can also be clamped exclusively between the housing cover 1 and the electronics cover 3.

[0123] FIG. 3 also shows how the suction port 6 and the pressure port 5 are each surrounded by a gasket, wherein the gasket of the suction port 6 surrounds both the pressure port 5 and the suction port 6 radially. The gasket of the pressure port 5 serves to seal off the pressure port 5 from the suction port 6, while the gasket of the suction port 6 serves to seal it off from the outside. The two gaskets can be formed together or as individual gaskets.

REFERENCE SIGNS

[0124] 1 housing cover [0125] 2 motor cover [0126] 3 electronics cover [0127] 4 drive shaft [0128] 5 pressure port [0129] 6 suction port [0130] 7 holding element [0131] 10 delivery device [0132] 11 accommodating well [0133] 12 intermediate housing structure [0134] 13 second delivery member [0135] 14 delivery member [0136] 15 gasket [0137] 16 connecting channel [0138] 17 recess groove [0139] 20 drive motor [0140] 23 stator [0141] 24 rotor [0142] 25 gasket [0143] 32 control electronics [0144] 35 gasket [0145] 40 fitting structure [0146] 41 passages