WO2013037534A1

WO2013037534A1 - Pump comprising an electric motor

Info

Publication number: WO2013037534A1
Application number: PCT/EP2012/064048
Authority: WO
Inventors: Alexander Fuchs; Ralf Rainer
Original assignee: Robert Bosch Gmbh
Priority date: 2011-09-13
Filing date: 2012-07-18
Publication date: 2013-03-21
Also published as: DE102011082587A1; EP2756195A1

Abstract

Disclosed is a pump (5) that has an electric motor (4) and is used to deliver a fluid, in particular in a motor vehicle. Said pump comprises at least one impeller (18) that has delivering elements (19) and can rotate about an axis of rotation (27), a working chamber on the at least one impeller (18), an electric motor (4) including a stator (13) and a rotor (16), a housing (8) that has an intake port (29) for feeding the fluid to be delivered into the working chamber (47) and a pressure port (30) for discharging the fluid to be delivered from the working chamber. The at least one impeller (18) including the delivering elements (19) as well as the electric motor (4) are arranged inside the housing (8), and the stator (13) is at least partly, in particular entirely, sealed by a sealing sleeve which forms a plain bearing unit for the at least one impeller (18), at least one impeller (18) being mounted on the plain bearing unit of the sealing sleeve. The stator (13) has one or more openings that are filled by the sealing sleeve, the plain bearing unit having a depression on each of the one or more openings.

Description

Description title

Pump with electric motor

The present invention relates to a pump with electric motor according to the preamble of claims 1 and 3, a method for manufacturing a pump with electric motor according to the preamble of claims 8 and 12 and a high-pressure injection system according to the preamble of claim 15.

State of the art

Pumps with electric motor are used for a wide variety of technical

Applications for conveying a fluid used. For example, fuel pumps are used to deliver fuel to an internal combustion engine. The electric motor of the pump comprises a stator and a rotor with

Permanent magnets.

In this case, the electric motor and the pump are arranged within a housing. Within the housing thus creates a space, in particular a working space in which there is the fluid to be pumped. Outside the housing, substances may be arranged, for example liquids, such as salt water, whose penetration is to be prevented within the housing of the pump, because this example, damage to the stator by corrosion

can cause. Also solids, such as

Dust or minute particles may cause damage to both the electric motor and the pump as it enters the enclosure enclosed by the housing.

For this reason, it is necessary to seal the pump with the electric motor permanently fluid-tight, on the one hand to escape the fluid to be delivered, For example, fuel to prevent out of the housing and on the other hand harmful substances or media from entering the housing enclosed by the housing with the pump and the

To prevent electric motor. It is known to surround the stator in a fluid-tight manner with a plastic sealing sleeve.

In this case, the housing of the pump with electric motor on a suction port opening and a pressure porting port through which the fluid to be pumped into the pump and is discharged. For a good functioning of the pump is the working space, which in particular on an impeller with

Forming conveyor elements, to position relative to the suction port opening and the pressure Portingöffnung to ensure a substantially loss of flow-free in and out of the fluid to be delivered.

DE 299 13 367 111 shows an internal gear pump with at least one internally toothed ring gear and a meshing, externally toothed impeller, with or without sickle, and with an electric drive, which is formed by the fact that the internal gear of a rotor of a brushless electric motor and a stator is arranged adjacent to the rotor, wherein the rotor containing the ring gear on the outside of a bearing or a

Sliding bearing is rotatably supported, wherein the stator is shielded and sealed relative to the rotor and the interior of the pump characterized in that the located between the stator and rotor bearings or bearings for liquid impermeable and is sealed at its two end faces each with a cover.

Disclosure of the Invention Advantages of the Invention

Inventive pump with electric motor, in particular for a motor vehicle, for conveying a fluid, comprising at least one impeller with

Conveying elements, of which a rotational movement about a rotational axis is executable, one on the at least one impeller existing

Working space, an electric motor with a stator and a rotor, a housing with a suction port opening for introducing the fluid to be conveyed in the Working space and a pressure porting opening for discharging the fluid to be delivered from the working space, wherein the at least one impeller are arranged with the conveying elements and the electric motor within the housing, the stator is at least partially, in particular completely, enclosed by a sealing sheath and the sealing sheath with at least one

Functional geometry, preferably with at least two or three

Functional geometries, is provided for positioning the at least one impeller and / or the working space relative to the suction port opening and the pressure porting, the housing with at least one

Counter function geometry, preferably with at least two or three

Counter function geometries, for positioning the impeller and / or the working space relative to the suction Portingöffnung and the pressure port opening is provided by the at least one functional geometry is in operative connection with the at least one counter function geometry, said at least one functional geometry as a step on the sealing sheath and the at least one mating geometry is formed as a step on the housing and the step on the sealing sheath rests directly against the step on the housing. Preferably, the step is annular.

In particular, the housing or a part of the housing, in particular a housing cover, is integrally formed with the suction port opening and the pressure porting opening and with the at least one mating function geometry. The housing or the part of the housing with the suction port opening of the pressure porting and the at least one counter function geometry is thus formed on a part of the housing and thereby occur in a production, for example by means of a die-cast aluminum process on the part of the housing between the suction and pressure -Portingöffnungen and the at least one counter function geometry only very small deviations. As a result, a very accurate positioning of the at least one

Impeller and / or the working space with respect to the suction Portingöffnung and the pressure port opening possible because the at least one functional geometry is in operative connection with the at least one counter function geometry.

Conveying elements, of which about a rotation axis, a rotational movement is executable, one on the at least one impeller existing

Working space, an electric motor with a stator and a rotor, a housing with a suction port opening for introducing the fluid to be conveyed into the working space and a pressure porting opening for discharging the fluid to be conveyed from the working space, said at least one impeller with the conveying elements and the electric motor are arranged within the housing, the stator is at least partially, in particular completely, enclosed by a sealing sheath, the sealing sheath forms a sliding bearing for the at least one impeller and at least one impeller on the plain bearing of the

Sealing sheath is mounted, wherein the stator has at least one opening and the at least one opening is filled with the sealing sheath and the slide bearing has at the at least one opening each have a recess. The at least one indentation on the sliding bearing on the sealing sheath makes it possible for the hydrodynamic lubricating wedge to lie between the external gear or the outer gear

at least one impeller and the slide bearing can form better, since a lubrication takes place in a promotion of, for example, fuel with the pump by means of the fuel. The slide bearing expediently has at least one indentation at least 0, 1 mm, 0.5 mm, 1 mm or 2 mm greater distance from the axis of rotation of the impeller mounted on the sliding bearing than outside the at least one indentation.

In a further embodiment, the stator comprises a soft magnetic core, in particular a laminated core, and the at least one opening of the stator is formed on the soft magnetic core, in particular the laminated core. The laminated core requires the at least one opening for magnetic and / or mechanical reasons. This at least one opening of the

Sheet metal packages is exploited on the one hand, that thereby a better positive connection between the sealing sleeve and the laminated core and thus the stator is made, since the sealing sleeve, in particular made of plastic, is introduced into the at least one opening.

In an additional embodiment, the at least one opening is substantially perpendicular to an axis of rotation of the at least one

Impeller. Preferably, the at least one impeller is indirectly or directly mounted on the sealing sheath and / or the pump is integrated in the electric motor or vice versa, by the rotor is formed by the at least one impeller, and / or the sealing sheath at least partially, in particular completely, made of plastic consists.

In a variant, the pump is a gear pump, in particular

Internal gear pump, so that the pump comprises two wheels as gears, in particular an inner and outer gear.

Method according to the invention for producing a pump with an electric motor, in particular a pump with electric motor described in this patent application, for conveying a fluid, comprising the steps of: providing at least one impeller with conveying elements, making available a housing with a suction port opening for introducing the to be pumped fluid into the working space and with a pressure port opening for discharging the fluid to be pumped from the working space and with at least one Gegenfunktionsgeometrie, provide an electric motor with a stator and a rotor for driving the pump, said at least one impeller with the Conveying elements and the electric motor can be arranged within the housing, mounting the impeller with conveying elements and the electric motor within the housing to the pump with electric motor, so that forms at the at least one impeller, a working space, the stator of a Di At least one functional geometry, preferably at least two or three, is enclosed on the sealing sheath

Functional geometries, is or will be provided and with the at least one functional geometry, the at least one impeller and / or the working space is positioned relative to the suction port opening and the pressure porting opening, wherein the housing or a part of the housing, in particular a housing cover , are made in one piece with the suction port opening, with the pressure port opening and with the at least one counter function geometry during prototyping.

The housing or part of the housing with the suction port opening, the pressure port opening and the at least one counter function geometry are in one piece in the prototyping of the housing or the part of the housing made, so that very small deviations between the suction and pressure Portingöffnung and the at least one

Counter function geometry exist. The at least one functional geometry on the sealing sheath is brought into operative connection or connection with the at least one counterfunctional geometry, so that dimensional deviations between the counterfunctional geometry and the suction and pressure porting opening also lead to deviations in the orientation of the at least one impeller and / or the working space guide the suction port and the pressure port. Due to the one-piece production, very small dimensional deviations occur between the suction port opening and the pressure port.

Porting opening and the at least one counter function geometry on the part of the housing, so that thereby a very accurate positioning of the at least one impeller and / or the working space with respect to the suction Portingöffnung and the pressure porting opening is possible.

Suitably, the housing or the part of the housing, in particular the housing cover, made of metal with only one Gusswerkzeugformteil and only one Gusswerkzeugformteil has Gießgeometrien for the suction Portingöffnung, the pressure porting opening and the at least one

Counter function geometry on.

In a further embodiment, the stator is made by injection molding

Plastic enclosed by the sealing sleeve. In particular, the housing or the part of the housing with the at least one counter function geometry and with the suction port opening and with the pressure porting opening with prototypes, preferably die-cast aluminum or aluminum, produced, preferably without a machining and / or the at least one functional geometry of the Sealing sheath is in operative connection, especially as indirect or immediate

positive connection, brought with the at least one Gegenfunktionsgeometrie. Machining is generally not required because the housing or part of the housing produced by die-casting aluminum or aluminum chill casting can be manufactured with sufficient accuracy. The suction port opening and pressure port opening is thus of sufficient accuracy with respect to the at least one Counter function geometry formed on the housing or the part of the housing. As a result, no costly machining of the housing is required in an advantageous manner.

Method according to the invention for producing a pump with an electric motor, in particular a pump with electric motor described in this patent application, for conveying a fluid, comprising the steps of: providing at least one impeller with conveying elements, making available a housing with a suction port opening for introducing the to be pumped fluid into the working space and with a pressure port opening for discharging the fluid to be pumped from the working space and with at least one Gegenfunktionsgeometrie, provide an electric motor with a stator and a rotor for driving the pump, said at least one impeller with the Conveying elements and the electric motor can be arranged within the housing, mounting the impeller with conveying elements and the electric motor within the housing to the pump with electric motor, so that forms a working space on the impeller, the stator enclosed by a sealing sheath is formed by the sealing sleeve, a sliding bearing for the at least one impeller, wherein when enclosing the stator with the sealing sheath, the sealing sheath is placed in at least one opening on the stator and the slide bearing at the at least one opening per a recess is formed. The at least one opening is required on the stator

magnetic and / or mechanical reasons and in this at least one opening, the sealing sheath is introduced when enclosing the stator, so that in addition a positive connection between the sealing sheath and the stator is produced. Due to this insertion of the sealing sheath, in particular made of plastic, in the at least one opening on the stator indentations are formed on the at least one opening and thereby a hydrodynamic lubricating wedge can be improved at a direct bearing at least one impeller on the sliding bearing of the sealing sheath.

In a further embodiment, the sealing sheath is introduced into at least one opening on a soft magnetic core, in particular a laminated core, of the stator. In a complementary variant, the one indentation is formed on the sliding bearing during a shrinkage of the sealing sheath. Upon hardening of the thermoplastic material, a shrinkage process occurs, which leads to the respective indentation being formed on the plain bearing in the region or on the at least one opening of the stator.

Suitably, an inner and outer gear is provided as the at least one impeller. The impeller can be mounted directly on the sealing sheath by the

Impeller, z. B. an external gear, rests directly on the sealing sheath or the impeller may be mounted indirectly on the sealing sheath by z. B. on the sealing sleeve a sliding bearing ring is attached and also the sliding bearing ring

Has indentation and on the plain bearing ring, which is attached to the sealing sheath, the impeller, z. B. an external gear, is mounted as a sliding bearing.

In an immediate storage of the impeller, in particular the

External gear, on the sealing sheath, the material of the sealing sheath may also have different material properties and / or consist of a different material, in particular of different plastic, for example, be made with a 2K injection molding process. At the slide bearing or an inner diameter of the sealing sleeve, the sealing sleeve consists of a plastic suitable for sliding bearing with a higher abrasion resistance than outside the sliding bearing where no high abrasion resistance is required.

In a supplementary embodiment, the plastic with thermally conductive additives, for. As ceramic and / or carbon, provided to the

To increase the thermal conductivity of the sealing envelope. As a result, the heat generated in the stator can be better conducted through the sealing sheath to the outside surface of the sealing sheath, d. H. the stator can be cooled better.

In a further embodiment, there is at least one between

Function geometry and at least one counter function geometry on the housing an indirect or immediate positive and / or non-positive connection. The at least one functional geometry on the sealing sheath and the at least one counter function geometry on the housing grip in this case Preferably, a positive fit with each other, thereby the stator is positioned with the sealing sheath relative to the housing with the suction port opening and the pressure Portingöffnung due to the geometric orientation of the at least one functional geometry of the sealing sheath and the at least one counter function geometry on the housing. As a housing while each component is preferably considered, which at least one

Has counter function geometry.

In a supplementary embodiment, the at least one

Functional geometry formed as at least one bulge and / or the at least counter function geometry is formed as a recess or vice versa, and preferably the at least one bulge is positively secured in the at least one recess.

Preferably, the at least one bulge has a conical geometry, for. B. as a centering cone on.

In a variant, the at least one recess is formed as a bore, preferably with a circular or rectangular cross-sectional shape.

In an additional embodiment, the sealing sheath is formed as an encapsulation or shrinkage or encapsulation and / or the sealing sheath is materially connected to the stator. The sealing sheath is thereby applied to the stator by means of injection molding in an encapsulation or by shrinking, for example as a shrink tube or a shrinkage structure.

In a supplementary embodiment, permanent magnets are integrated in the rotor and the permanent magnets are integrated in the impeller, so that the rotor is formed by the impeller.

In a further embodiment, the conveying elements are blades or teeth of a gear.

In an additional embodiment of the soft magnetic core and the windings are completely enclosed as electromagnets of the sealing sheath and the electrical contact elements are partially enclosed by the sealing sheath, so that a part of the contact elements is arranged outside of the sealing sheath.

In a supplementary embodiment, the stator, in particular the soft magnetic core, the windings and partly the electrical

Contact elements, fluid-tight enclosed by the sealing sheath.

Inventive high-pressure injection system for an internal combustion engine, in particular for a motor vehicle, comprising a high-pressure pump, a high-pressure rail, an electric feed pump for conveying a fuel from a fuel tank to the high-pressure pump, wherein the electric

Pre-feed pump is designed as a described in this patent application pump with electric motor.

In a further embodiment, the pump is integrated in the electric motor or vice versa, preferably, the pump and the electric motor are inseparable units.

In a further embodiment, the rotor is partially made of sheet metal plates. Preferably, the metal plates are surrounded by an insulating layer. The insulation around the metal plates and the formation of the rest of rotor made of sheet metal plates has the task that in the rotor no or very little

Eddy currents occur.

In a further embodiment, the rotor is at least partially, in particular completely made of sintered steel.

In a further embodiment, the pump is an external gear pump or a centrifugal pump or a vane cell pump.

Suitably, the pump with, preferably integrated, electric motor comprises a, preferably electronic, control unit for controlling the

Energizing the electromagnets.

In an additional embodiment, the pump is a turbomachine. Suitably consists of the housing of the prefeed pump and / or the housing of the high-pressure pump and / or the inner and / or outer gear at least partially, in particular completely, made of metal, for. As steel or aluminum.

In particular, the delivery rate of the electrical feed pump can be controlled and / or regulated.

Brief description of the drawings

Hereinafter, embodiments of the invention below

With reference to the accompanying drawings described in more detail. It shows:

1 is a highly schematic view of a high-pressure injection system,

2 is a perspective view of a prefeed pump without housing and a stator without sealing sheath,

3 is an exploded view of the prefeed pump of FIG. 2,

Fig. 4 is a perspective view of the stator with sealing sheath and

two sealing rings without functional geometry,

5 shows a section of the stator with sealing sleeve according to FIG. 4, FIG.

Fig. 6 shows a section of the stator with sealing sheath and a housing cover with function and counter function geometry in a first

Embodiment,

FIG. 7 shows a detailed representation from FIG. 6 of the functional geometry before a deformation of the functional geometry, FIG.

8 is a detailed view of FIG. 6 of the functional geometry after a deformation of the functional geometry, FIG.

Fig. 9 is a section of the stator with sealing sheath and a housing cover with function and counter function geometry in a second

Exemplary embodiment and a view of a cast tool molding,

10 shows a section of the stator with sealing sleeve and a housing cover with function and counter function geometry in a third

Embodiment,

Fig. 1 1 shows a section of a laminated core of the stator with the sealing sleeve as a sliding bearing for the external gear and

Fig. 12 is a view of a motor vehicle.

Embodiments of the invention

FIG. 1 shows a pump arrangement 1 of a high-pressure injection system 2. An electric prefeed pump 3 conveys fuel from a fuel tank 41 through a fuel line 35. Subsequently, the fuel is conveyed from the electric prefeed pump 3 to a high-pressure pump 7. The high-pressure pump 7 is of an internal combustion engine 39 by means of a

Drive shaft 44 driven.

The electric prefeed pump 3 has an electric motor 4 and a pump 5 (FIGS. 2 and 3). In this case, the electric motor 4 of the pump 5 is integrated into the pump 5 and further, the electric prefeed pump 3 at the

High pressure pump 7 arranged directly. The high-pressure pump 7 delivers fuel under high pressure, for example, a pressure of 1000, 3000 or 4000 bar through a high-pressure fuel line 36 to a high-pressure rail 42. From the high-pressure rail 42 of the fuel under high pressure from an injector 43 a combustion chamber, not shown

Internal combustion engine 39 supplied. The non-combustion fuel is returned to the by means of a return fuel line 37

Fuel tank 41 returned. A porting opening 28 as a pressure porting opening 30 (FIG. 2) of the electric prefeed pump 3 are connected to the high-pressure pump 7 without an external connection (FIGS. 1 and 3). The mounting position of the electric prefeed pump 3 to the high-pressure pump 7 is to this effect chosen that can be passed by short hydraulic connections of the fuel from the pressure side of the feed pump 3 to the suction side of the high-pressure pump 7. In the fuel line 35 from the fuel tank 41 to the electric feed pump 3, a fuel filter 38 is installed. As a result, the fuel line 35 can be formed inexpensively from the fuel tank 41 to the electric prefeed pump 3, since it does not have to withstand excess pressure. The electric motor 4 (FIGS. 2 and 3) of the electric prefeed pump 3 is operated with three-phase current or alternating current and can be controlled and / or regulated in power. The three-phase current or alternating current for the electric motor 4 is provided by a power electronics, not shown, from a DC voltage network of a vehicle electrical system of a motor vehicle 40. The electric prefeed pump 3 is thus an electronically pumped prefeed pump 3rd

The electric prefeed pump 3 has a housing 8 with a housing pot 10 and a housing cover 9 (FIG. 3). Within the housing 8 of the prefeed pump 3, the pump 5 as internal gear 6 and

Gear pump 26 and the electric motor 4 is arranged. The housing pot 10 is provided with a recess 57. The electric motor 4 has a stator 13 with windings 14 as electromagnets 15 and a soft iron core 45 as a soft magnetic core 32, which is formed as a laminated core 33.

Within the stator 13, the pump 5 is positioned as an internal gear pump 6 with an internal gear 22 with an internal gear ring 23 and an external gear 24 with an external gear ring 25. The inner and outer gear 22, 24 thus represents a gear 20 and an impeller 18 and the inner and outer toothed ring 23, 25 have teeth 21 as conveying elements 19. Between the inner and outer gear 22, 24, a working space 47 is formed. In the external gear 24 permanent magnets 17 are installed, so that the external gear 24 also forms a rotor 16 of the electric motor 4. The electric motor 4 is thus integrated into the pump 5 or vice versa. The electromagnets 15 of the stator 13 are alternately energized, so that due to the on the

Electromagnet 15 resulting magnetic field of the rotor 16 and the

External gear 24 is set in a rotational movement about a rotation axis 27. The housing cover 9 serves as a bearing 1 1 or thrust bearing 11 or sliding bearing 1 1 for the inner or outer gear 22, 24. Further, in the housing cover 9, a suction port opening 29 and a suction channel 29 and the pressure porting 30th or a pressure channel 30, each as porting openings 28, incorporated. Through the suction port opening 29, the fluid to be delivered, namely fuel, flows into the prefeed pump 3 from the pressure port opening 30, the fuel flows out of the prefeed pump 3 again. In addition, the housing pot 9 and the housing cover 10 each have three holes 46, in which not shown screws for screwing the housing pot 9 and the

Housing cover 10 are positioned.

In Fig. 4 and 5, the stator 3 is shown, which is enclosed by a sealing sheath 31 as encapsulation. The sealing sheath 31 represents an encapsulation 31 or an injection 31 and is by means of injection molding in one

Injection molding tool produced while materially connected to the stator 31. In this case, both the electromagnets 15 and the soft iron core 45 of the stator 13 are completely enclosed by the sealing sheath 31 of the sealing sheath 31 as components of the stator 13. An electrical contact element 34 as a further component of the stator 13 comprises the contact pin 48 and the contact line 49. Several contact pins 48 with associated contact lines 49 are present on the stator 13, so that the stator 13 also has a plurality of electrical contact elements 34. In Fig. 5 is only one

electrical contact element 34 shown. By means of the electric

Contact elements 34, the windings 14 are supplied with winding wires 56 of the stator 13. The contact pins 48 are partially not enclosed by the sealing sleeve 31 made of thermoplastic material, so that at this, not enclosed by the sealing sleeve 31 part of the electrical

Contact elements 34 can be brought into mechanical and electrical connection with mating contact elements, not shown in the

Energization of Wcklungen 14 of the stator 13. The sealing sheath 31 further has a plug-in collar 55. The plug-in collar 55 (FIGS. 4 and 5) is arranged in the recess 57 of the housing pot 10 after assembly of the electric prefeed pump 3 (not shown). The sealing sleeve 31 has two grooves 51 for receiving a respective sealing ring 54.

By means of the two completely circumferential sealing rings 54 as seals 53 can the plug-in collar 55 and the sealing sleeve 31 with respect to the housing pot 10 and the housing cover 9 are sealed fluid-tight. The two sealing rings 54 thus prevent, on the one hand, the penetration of harmful media into the interior space enclosed by the housing 8 and, on the other hand, the fluid conveyed by the internal gear pump 6, namely fuel, can not reach the outside of the housing 8. The grooves 51 in this case have to the rotation axis 27 a greater distance than the windings 14. The grooves 51 are thereby arranged on an outer diameter of the stator 13 and the sealing sleeve 31, thereby characterized for the grooves 51 no additional radial space between the windings 14th and the external gear 24 is needed.

The sealing sheath 31 forms a sliding bearing 66 for the external gear 24.

6 to 8 is the first embodiment for the execution of

Functional geometries 50 on the sealing sheath 31 and Gegenfunktionsgeometrien 58 on the housing 8, namely the housing cover 9 as a part 12 of

Housing 8 shown. From the stator 13 6 to 8, only the sealing sheath 31 are shown in Figs. The sealing sheath 31 in this case has three functional geometries 50, of which two are shown in FIG. 6 and only one in FIGS. 7 and 8. The

Functional geometry 50 represents a bulge 59, which as

Centering cone 60 is formed. Within the centering cone 60 is a centric

Deformation channel 61 available. The three centering cones 60 on the sealing sleeve 31 have elastic properties. In this case, the remaining part of the sealing sheath 31 may also have these elastic properties or only the centering cone 60, d. H. the functional geometries 50, have these properties, so that in this last case, the sealing sheath 31 with the functional geometries

50 is produced by means of a 2K injection molding process with different elastic properties of the sealing sleeve 31. On the housing cover 9, the three counter function geometries 58 are present, which are formed as bores 65 recesses 64. The housing cover 9 or the part 12 of the housing 8 is made by means of an aluminum die casting process

Made of aluminum and produced by means of the

Aluminum die-casting process both the counter function geometries 58 as recesses 64 and the suction port opening 29 and the pressure porting port 30 are made with. As a result, no costly additional post-processing, in particular machining after the prototyping of the housing cover 9, is required in an advantageous manner and already after the Prototypes of the housing cover 9, the Gegenfunktionsgeometrien 58 and the suction and pressure Portingöffnung 29, 30 are present. The outer gear 24 is indirectly or directly mounted on the sealing sheath 31, so that due to a positioning of the sealing sheath 31 relative to the housing cover 9 and the position of the working space 47 and the inner and outer gear 22, 24 is defined relative to the housing cover 9 thereby. When mounting the electric prefeed pump 3, the sealing sleeve 31 is first on the

Housing cover 9 placed to the effect that the conical centering cone 60 as shown in Fig. 7 from the boundaries of the housing cover 9 rest on the holes 65. In this case, no or substantially no elastic deformation of the elastic centering cone 60 occurs in FIG. 7. In the manufacture of the housing cover 9 by means of the aluminum die-casting process, slight manufacturing inaccuracies in size or occur

Diameter of the bore 65. To compensate for these inaccuracies, the centering cone 60 at the lower end in the region of the remaining sealing sleeve 31 has a larger diameter than the bore 65, d. H. an excess. In the final assembly of the stator 13 with the sealing sheath 31 on the

Housing cover 9, the sealing sheath 31 with the centering cone 60 in the

Drilled holes 65 as shown in Fig. 8, so that thereby the centering cone 60 elastically deformed. The deformation of the Zentrierkegels 60 is thereby additionally facilitated by this centric the

Deformation channel 61 has, and in the region of the lower end of the deformation channel 61, this at least partially closed. This makes it possible, even with different sizes of the bore 65 a gap-free positive connection between the centering 60 outside and the

To achieve bore 65 on the housing cover 9. In the embodiment of the electric prefeed pump 3 shown in FIGS. 6 to 8, the sealing of the housing 8 to the outside does not occur with the functional geometry 50, ie. H. the centering cone 60, but by means of in Figs. 4 and 5

illustrated seals 53 in the grooves 51, d. H. the seals 53 in the two grooves 51st

FIG. 9 shows a second exemplary embodiment of the design of the function and counter function geometry 50, 58 on the electric prefeed pump 3. The counter function geometry 58 on the housing cover 9 is designed as a step 62 and the functional geometry 50 on the sealing cover 31 is also formed as a level 62. The level 62 is as on the

Housing cover 9 is formed as a completely encircling ring and the step 62 on the sealing sheath 31 is also formed as a completely encircling ring and in Fig. 9, the ring is cut only once due to the sectional formation and thus the two stages 62 in Fig. 9 only once shown.

The two stages 62 are formed within the windings 14 and at the two stages 62 are the sealing sheath 31 and the housing cover 9 directly to each other. In addition, between the sealing sleeve 31 and the housing cover 9, the seal 53 is arranged as a sealing ring 54, so that the housing 8 of the electric prefeed pump 3 is sealed fluid-tight to the outside.

In Fig. 10 is a third embodiment of the functional and

Counter function geometry 50, 58 of the electric feed pump 3 shown. In the following, only the differences from the second exemplary embodiment according to FIG. 9 will be described essentially. The level 62 as the

Housing cover 9 and the sealing sheath 31 is formed outside of the windings 14 and outside of the seal 53.

By means of the step 62 as a functional geometry 50 on the sealing sheath 31 and the counter function geometry 58 on the housing cover 9 is the

Housing cover 9 sufficiently positioned or centered with respect to the inner and outer gear 22, 24. Thereby, the suction port opening 29 and the pressure port opening 30 are positioned according to the working space 47 between the inner and outer gears 22, 24 in a sufficient accuracy , The housing cover 9 is by means of a

Aluminum die casting process with a cast tool molding 68 (FIG. 9). The mold tool part 67 has corresponding

Gießgeometrien 68, so that thereby on the cast cover 9, among other things, the suction port opening 29, the pressure porting opening 30 and the

Counter function geometry 58 can be formed or manufactured as step 62. These

Gießgeometrien 69 are present on only one mold tool part 68 for the housing cover 9, thereby characterized in the

Aluminum die casting process only very small deviations between the counter function geometry 58 and the suction and pressure porting opening 29, 30 are present. Since the sealing sleeve 31 with the functional geometry 50 at the

Counter function geometry 58 is centered or aligned thereby even very small deviations in the orientation of the suction port opening 29 and the pressure porting opening 30 with respect to the inner and outer gear 22, 24 and the working space 47 on. Advantageously, this is a complex machining of the housing cover 9 for a sufficiently accurate positioning of the suction port opening and the

Pressure port opening 29, 30 with respect to the inner and outer gear 22, 24 and the working space 47 is not required.

In Fig. 1 1, a section of the laminated core 33 is shown. The laminated core 33 has openings 63 for magnetic and mechanical reasons. During encapsulation of the stator 13 with the plastic of the sealing envelope 31, the plastic of the sealing envelope 31 penetrates into these openings 63, thereby forming an additional form-fitting connection between the sealing envelope 31 and the stator 13 or the laminated core 33. At the sealing sheath 31 is at the radial inner end of the sliding bearing 66 for the external gear 24th

educated. In this case, the external gear 24 is mounted directly on the slide bearing 66 and when pumping fuel with the pump 5, the fuel is used for hydrodynamic lubrication between the external gear 24 and the slide bearing 66 on the sealing sleeve 31. When hardening and cooling of the thermoplastic material of the sealing sleeve 31st occurs shrinkage of the plastic of the sealing sheath 31, so that in each case a recess 67 is formed on the sliding bearing 66 in the region of the openings 63. These recesses 67 support and promote the construction of a hydrodynamic lubricating wedge between the funded by the pump 5 fluid, in particular fuel, between the sliding bearing 66 and the outer gear 24th

Overall, with the inventive pump 5 with

Electric motor 4 major advantages associated. The housing cover 9 is the original molding by means of a primary molding process, for. B. one

Aluminum die casting process, manufactured in one piece with the primary mold and the master mold has corresponding Gießgeometrien 69 for the suction Portingöffnung 29, the pressure porting opening 30 and the at least one

Counter function geometry 58, so that very small deviations between the at least one counter function geometry 58 and the suction port opening 30 and the pressure porting opening 30 is thereby formed during prototyping. Since the sealing sheath 31 with respect to the stator 13 by means of the functional geometry 50 the housing cover 9 is aligned and on the sealing sheath 31 the

Outer gear 24 is mounted, thereby occur only very small

Dimensional deviations between the inner and outer gear 22, 24 and the working space 47 and the suction Portingöffnung 29 and the pressure Portingöffnung 30 on. The shrinkage of the thermoplastic material of the sealing sheath 31 entering forming indentations 67 on the

Sliding bearings 66 increase and improve a hydrodynamic wedge between the sliding bearing 66 and the external gear 24.

Claims

Pump (5) with electric motor (4), in particular for a motor vehicle (40), for conveying a fluid

- At least one impeller (18) with conveying elements (19) from which about a rotation axis (27) is a rotational movement executable,

- One on the at least one impeller (18) existing

Working space (47),

an electric motor (4) having a stator (13) and a rotor (16),

- A housing (8) with a suction port opening (29) for introducing the fluid to be conveyed into the working space (47) and a pressure Portingöffnung (30) for discharging the fluid to be conveyed from the working space (47),

- Wherein the at least one impeller (18) with the conveying elements (19) and the electric motor (4) within the housing (8)

are arranged

- The stator (13) at least partially, in particular completely, by a sealing sheath (31) is enclosed and the sealing sheath (31) with at least one functional geometry (50), preferably with at least two or three functional geometries (50), provided for positioning the at least one impeller (18) and / or the working space (47) relative to the suction port (29) and the pressure port (30),

- The housing (8) with at least one counter function geometry (58), preferably with at least two or three

Counter function geometries (58), for positioning the impeller (18) and / or the working space (47) relative to the suction Portingöffnung (29) and the pressure Portingöffnung (30) is provided by the at least one functional geometry (50) in

Operative connection with the at least one counter function geometry (58), characterized in that the at least one functional geometry (50) is formed as a step (62) on the sealing sheath (31) and the at least one mating functional geometry (58) is formed as a step (62) on the housing (8) and the step (62 ) rests against the sealing sheath (31) directly on the step (62) on the housing (8).

Pump with electric motor according to claim 1, characterized in that the housing (8) or a part (12) of the housing (8), in particular a housing cover (9), with the suction port opening (29) and the pressure porting port (30 ) as well as with the at least one

Counter function geometry (58) is integrally formed.

- One on the at least one impeller (18) existing

Working space (47),

an electric motor (4) having a stator (13) and a rotor (16),

- wherein the at least one impeller (18) with the conveying elements (19) and the electric motor (4) are arranged within the housing (8),

- The stator (13) at least partially, in particular completely, by a sealing sheath (31) is enclosed, - The sealing sheath (31) forms a sliding bearing (66) for the at least one impeller (18) and at least one impeller (18) on the

Slide bearing (66) of the sealing sheath (31) is mounted, characterized in that the stator (13) has at least one opening (63) and the at least one opening (63) with the sealing sheath (31) is filled and the sliding bearing (66) has at least one opening (63) each having a recess (67).

4. Pump with electric motor according to claim 3, characterized in that the stator (13) comprises a soft magnetic core (32), in particular a laminated core (33), and the at least one opening (63) of the stator (13) on the soft magnetic core (32), in particular the laminated core (33) is formed.

5. Pump with electric motor according to claim 3 or 4, characterized in that the at least one opening (63) is substantially perpendicular to a rotation axis (27) of the at least one impeller (18).

6. Pump with electric motor according to one or more of the preceding claims, characterized in that the at least one impeller (18) on the sealing sheath (31) is mounted directly or indirectly

and or

the pump (5) is integrated in the electric motor (4) or vice versa, by the rotor (16) is formed by the at least one impeller (18), and / or

the sealing sheath (31) at least partially, in particular completely, consists of plastic.

Pump with electric motor according to one or more of the preceding claims, characterized in that the pump (5) is a gear pump (6), in particular

Internal gear pump (6), is, so that the pump (5) has two wheels as gears (20), in particular an internal gear (22) and a

External gear (24) includes.

Method for producing a pump (5) with electric motor (4), in particular a pump (5) with electric motor (4) according to one or more of claims 1, 2 and 5 to 7, for conveying a fluid, with the steps:

- Provide at least one impeller (18) with

Conveying elements (19),

- Providing a housing (8) with a suction Portingöffnung (29) for introducing the fluid to be conveyed into the working space (47) and with a pressure porting opening (30) for discharging the fluid to be conveyed from the working space (47) and with at least one counter function geometry (58),

- Providing an electric motor (4) with a stator (13) and a rotor (16) for driving the pump (5),

- Mounting the impeller (18) with conveying elements (19) and the electric motor (4) within the housing (8) to the pump (5) with electric motor (4), so that at the at least one impeller (18) has a working space ( 47), - The stator (13) by a sealing sheath (31) is enclosed and on the sealing sheath (31) at least one functional geometry (50),

preferably at least two or three functional geometries (50) are provided and / or with the at least one functional geometry (50) the at least one impeller (18) and / or the working space (47) relative to the suction port opening (29) and the pressure porting opening (30) is positioned, characterized in that the housing (8) or a part (12) of the housing (8), in particular a housing cover (9), with the suction port opening (29), with the Pressure Portingöffnung (30) and with the at least one

Gegenfunktionsgeometrie (58) are produced in one piece during prototyping.

9. The method according to claim 8, characterized in that the housing (8) or the part (12) of the housing (8), in particular the housing cover (9), are made of metal with only one Gusswerkzeugformteil (68) and only one Cast tool molding (68)

Gießgeometrien (69) for the suction Portingöffnung (29), the pressure Portingöffnung (30) and the at least one Gegenfunktionsgeometrie (58).

10. The method according to claim 8 or 9, characterized in that the stator (13) is enclosed by injection molding of plastic from the sealing sheath (31).

1 1. A method according to one or more of claims 8 to 10, characterized in that the housing (8) or the part (12) of the housing (8) with the at least one counter function geometry (58) and with the suction port opening (29) and with the pressure porting opening (30) with prototypes, preferably Die-cast aluminum or aluminum chill casting is produced, preferably without a machining operation

and or

the at least one functional geometry (50) on the sealing sheath (31) in operative connection, in particular as an indirect or direct positive connection, with the at least one

Counter function geometry (58) is brought.

12. A method for producing a pump (5) with electric motor (4),

in particular a pump (5) with electric motor (4) according to one or more of claims 3 to 7, for conveying a fluid, with the steps:

- Provide at least one impeller (18) with

Conveying elements (19),

- Mounting the impeller (18) with conveying elements (19) and the electric motor (4) within the housing (8) to the pump (5) with electric motor (4), so that at the at least one impeller (18) has a working space ( 47),

- The stator (13) is enclosed by a sealing sheath (31),

- of the sealing sheath (31) a sliding bearing (66) for the at least one impeller (18) is formed, characterized in that when enclosing the stator (13) with the sealing sheath (31) the sealing sheath (31) in at least one opening (63) on the stator (13) is introduced and from the sliding bearing (66) at the at least one opening ( 63) depending on a recess (67) is formed.

13. The method according to claim 12, characterized in that the sealing sheath (31) in at least one opening (63) on a

soft magnetic core (32), in particular a laminated core (33), of the stator (13) is introduced.

14. The method according to claim 12 or 13, characterized in that the one indentation (67) on the plain bearing (66) during

Shrinkage of the sealing sheath (31) is formed.

15. High-pressure injection system (2) for an internal combustion engine (39),

in particular for a motor vehicle (40)

a high pressure pump (7),

a high pressure rail (42),

an electric prefeed pump (3) for conveying a fuel from a fuel tank (41) to the high-pressure pump (7), characterized in that the electric prefeed pump (3) as a pump (5) with electric motor (3) according to one or more of Claims 1 to 7 is formed.