DE102016206062A1 - Rotary piston pump - Google Patents

Abstract

Rotary piston pump (16) for conveying a fluid, in particular fuel, comprising at least two impellers (52) with conveying elements (53), of which a rotational movement is executable around a respective rotation axis (61), a working space present on the at least two impellers (52) for directing the fluid through the working space, an electric motor (17) with a stator (47) and a rotor (50), a sealing element for sealing the working space (62) of the stator (47), a multipart housing (42) with a first housing component (44) and a second housing component (43), wherein the first housing component (44) also acts as the sealing element (18) for sealing the working space (62) of the stator (47) such that upon leakage at the working space (62) the leakage fluid, in particular exclusively, enters the environment and preferably no leakage fluid reaches the stator.

Description

The present invention relates to a rotary piston pump according to the preamble of claim 1 and a high-pressure injection system according to the preamble of claim 15.

State of the art

Rotary piston pumps with electric motor are used for various technical applications for pumping a fluid. For example, prefeed pumps serve as fuel pumps for conveying fuel to a high-pressure pump. In high-pressure injection systems, gerotor pumps with an internal gear and an eccentrically mounted external gear are used as prefeed pumps. The gerotor pumps in this case have an inflow channel, which opens into an inflow working space to introduce the fluid to be conveyed into the inflow working space and an outflow channel, which opens into an outflow working space to divert the fluid to be delivered from the Abströmarbeitsraum. The inflow working space thus represents a suction side of a working space of the gerotor pump and the outflow working space represents a pressure side of the working space. A working space of the gerotor pumps comprising the inflow working space and the outflow working space is bounded by a housing. Within the working space, the internal gear and the external gear are mounted by means of a sliding bearing on the housing. The axis of rotation of the internal gear has a distance from the axis of rotation of the external gear, that is, the inner and the outer gear are mounted eccentrically to each other.

A substantially plate-shaped housing component has an inflow channel and an outflow channel. At a substantially cup-shaped second housing component, a bearing neck for radial sliding bearing of the inner and outer gear is formed. The first and second housing components define an annular space for receiving the stator and also the working space. A seal, which is annular, thereby seals the working space of the annular space with the stator. In the event of a leak on this seal as a sealing element, the fluid to be delivered, for example fuel, reaches the annular space with the stator. In the stator windings are arranged as electromagnets and these have a high temperature. Failure of this seal thus leads to significant damage to the rotary piston pump disadvantageously. The fuel evaporates while the electromagnet and thereby leads to irreparable damage to the rotary piston pump and possibly also outside of the rotary piston pump with an installation of the rotary piston pump in a motor vehicle.

From the DE 36 24 532 C2 For example, there is known a vane or internal gear pump having a plurality of sealed delivery cells whose volume changes from a minimum to a maximum value and back during one revolution. The pump is used in particular for fuel delivery of an internal combustion engine. With axially entering into the feed cells suction and pressure channels, the mouth cross-sections are designed for a promotion without internal compression, but such is created by against axial surfaces of the pump parts applied, check valves forming fixed thrust washers.

From the DE 34 06 349 A1 a displacement machine with at least two gear machines is known, which is assigned a separate or common hydraulic circuit, and their common flow is variable by a control means, wherein the control means is arranged in a housing part of the positive displacement machine.

The DE 299 13 367 U1 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 ring gear disposed inside a rotor of a brushless electric motor and the rotor adjacent to a stator is, wherein the rotor containing the ring gear is rotatably supported on the outside by a bearing or a sliding bearing, 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 tightly connected at its two end faces in each case with a cover.

Disclosure of the invention

Advantages of the invention

Rotary piston pump according to the invention for conveying a fluid, in particular fuel, comprising at least two wheels with conveying elements, of which a rotational movement is rotatable about each axis of rotation, a work space provided on the at least two wheels for guiding the fluid through the working space, an electric motor with a stator and a rotor, a sealing element for sealing the working space of the stator, a multi-part housing having a first housing component and a second housing component, wherein the first housing component also as the sealing element for sealing the working space of the stator to that effect acts that in a leakage at the working space, the leakage fluid, in particular exclusively, enters the environment or can be derived in the environment and preferably no leakage fluid reaches the stator or no leakage fluid can be conducted to the stator. The geometry of the first housing component, in particular the dividing wall and / or at least one further wall of the first housing component, is designed such that leakage fluid, in particular leakage fuel, in the event of a leakage at a working space seal exclusively in the environment and preferably not in the space on the Stator arrives. Leakage fluid, which is not retained by the working space seal, thus passes exclusively into the environment. As a result, damage to the rotary piston pump can be avoided in a large extent in a leakage at the working space seal in an advantageous manner. Leakage fluid is preferably the fluid to be delivered, the erroneously or unintentionally from the working space, preferably at a working space seal, flows out, that does not flow through the outflow channel or the pressure kidney from the working space.

In a supplementary variant, the first housing component, in particular exclusively the first housing component, defines a space, in particular annular space, and the stator is arranged inside the space and / or the first housing component has at least one wall and / or a partition wall as a sealing element for sealing the working space includes the stator.

In an additional embodiment, the partition wall of the first housing component is cylinder jacket-shaped and axially aligned and / or the partition separates in the radial direction, in particular exclusively, the working space of the stator fluid-tight and / or the partition is at least one further portion of the first housing component, in particular the inner first part housing component, integrally formed.

Suitably, the first housing component is formed in two parts with a, in particular in the radial direction, inner first part housing component and one, in particular in the radial direction, outer first part housing component and preferably the inner first part housing component acts to the effect that at a leakage at the Working space the leakage fluid, especially exclusively, enters the environment and preferably no leakage fluid reaches the stator.

In an additional embodiment, the space with the stator is formed radially between the inner first part housing component and the outer first part housing component and / or the space with the stator is limited exclusively by the first housing component and / or the separation wall is at the inner formed first part housing component and / or the partition wall with at least one further portion of the first housing component, in particular the inner first part housing component, is integrally formed.

In a supplementary variant, the first housing component is cup-shaped and the second housing component is lid-shaped.

In an additional embodiment, the walls of the first housing component are formed radially outside the at least two wheels and preferably no wall of the second housing component is formed.

In a further embodiment, the first housing component with the second housing component with at least one fastening element, in particular a screw, preferably releasably connected to each other and / or between the first housing component and the second housing component, a working space seal, in particular O-ring seal to fluid-tight sealing of the working space is arranged with respect to the environment.

Preferably, the working space seal between the first and second housing component is arranged such that at leakage of the working space seal emerging from the working space seal leakage fluid into the environment, in particular exclusively in the environment, and preferably the leakage fluid does not reach the stator reaches and / or a perpendicular to a rotational axis of an impeller, in particular gear, aligned cutting plane, which is aligned centrally between the two axial ends of the impeller in the axial direction, the partition wall intersects and / or the working space seal does not intersect.

In a supplementary variant, the rotary piston pump comprises a bearing neck for radially supporting the at least two running wheels and the bearing neck on the second housing component, in particular integrally formed on the second housing component.

Suitably, the at least two wheels are axially mounted on the first housing component and / or on the second housing component and / or the at least two wheels are mounted axially on the bearing neck.

In an additional embodiment, the outer first part housing component comprises at least one outer partition for radial fluid-tight separation of the space on the stator to the environment and / or between the inner first part housing component and the outer first part housing component at least one stator seal, in particular Labyrinth seal, designed for fluid-tight sealing of the space on the stator with respect to the environment.

In a further embodiment, the conveying elements are teeth of a gear and / or the rotary piston pump is a gear pump, preferably internal gear pump, in particular gerotor pump.

In an additional embodiment of the electric motor is integrated into the rotary piston pump by a rotor of the electric motor forms an impeller, in particular permanent magnets are installed in an impeller, so that the impeller with the permanent magnet forms the rotor and / or the capacity of the rotary piston pump, preferably with integrated Electric motor, is controllable and / or regulated, in particular by the power and / or speed of the electric motor is controllable and / or regulated.

The rotary piston pump expediently comprises an inflow channel opening into the inflow working space for introducing the fluid to be conveyed into the inflow working space and an outflow channel opening into the outflow working space for diverting the fluid to be conveyed from the outflow working space.

In an additional variant, the inflow channel and / or the outflow channel is formed on the second housing component. Thus, no inflow and / or outflow channel is formed on the first housing component, so that the first housing component assumes no hydraulic function in this regard for introducing and discharging the fluid into and out of the working space.

In a supplementary embodiment, a first radial bearing geometry is designed as a bearing neck and the bearing neck is arranged within a bearing bore of a first impeller or vice versa, so that by means of the bearing stub, the first impeller is radially mounted.

In an additional embodiment, a second radial bearing geometry as an at least partially, in particular completely, ring-shaped bearing layer is formed and the bearing stage is located on a complementary formed bearing recess of a second impeller or vice versa, so that by means of the bearing stage, the second impeller is radially mounted. The first and / or second radial bearing geometry may have any geometry or shape, for example, be formed as a ring which is arranged in a complementary annular groove on the at least one impeller.

In a further variant, the internal gear pump comprises an internal gear preferably with the bearing bore as the first impeller and an external gear preferably with the bearing recess as a second impeller.

In an additional embodiment, the second housing component with the at least two radial bearing geometries, in particular all radial bearing geometries, as the second housing component is substantially plate-shaped without consideration of at least two radial bearing geometries.

Inventive high pressure injection system for an internal combustion engine, comprising a high pressure pump, a high pressure rail, a prefeed pump for conveying a fuel from a fuel tank through a fuel line to the high pressure pump, wherein the prefeed pump is designed as a high pressure pump described in this patent application.

Preferably, the internal gear pump comprises an internal gear having an internal gear and an external gear having an external gear, wherein the teeth of the internal gear mesh with the teeth of the external gear and the working space is formed between the internal gear and the external gear.

In an additional embodiment, the internal gear is mounted eccentrically to the external gear.

Suitably, the rotary piston pump is a rotary piston pump.

Suitably, the rotary piston pump with, preferably integrated, electric motor comprises a, preferably electronic, power electronics for controlling the energization of the electromagnets and / or the electric motor is a brushless or electronically commutated electric motor.

Brief description of the drawings

Hereinafter, embodiments of the invention will be described in more detail with reference to the accompanying drawings. It shows:

1 a cross section of a high-pressure pump for conveying a fluid,

2 a section AA according to 1 a roller with roller shoe and a drive shaft,

3 a highly schematic view of a high-pressure injection system,

4 a greatly simplified cross-section of the high-pressure pump with a prefeed pump,

5 a perspective view of a prefeed pump without housing,

6 an exploded view of the feed pump according to 5 and 8th with housing,

7 a cross-section of an inner and outer gear of the feed pump according to 5 ,

8th a greatly simplified cross section of the feed pump in a first embodiment and

9 a greatly simplified cross section of the feed pump in a second embodiment.

Embodiments of the invention

In 1 is a cross section of a high pressure pump 1 shown for conveying fuel. The high pressure pump 1 serves to fuel, z. As gasoline or diesel, to an internal combustion engine 39 for a motor vehicle under high pressure to promote. The maximum of the high pressure pump 1 producible pressure is for example in a range between 1000 and 3000 bar.

The high pressure pump 1 has a drive shaft 2 with two cams 3 on that around an axis of rotation 26 performs a rotational movement. The rotation axis 26 lies in the drawing plane of 1 and is perpendicular to the plane of 2 , A piston 5 is in a cylinder 6 as a piston guide 7 stored, by a high-pressure pump housing 8th the high pressure pump 1 is formed. A high pressure workroom 29 is from the cylinder 6 as a piston guide 7 , the high-pressure pump housing 8th and the piston 5 limited. In the high pressure workroom 29 opens an inlet channel 22 with an inlet valve 19 and an exhaust duct 24 with an exhaust valve 20 , Through the inlet channel 22 with an inlet opening 21 the fuel flows into the high-pressure working space 29 in and through the outlet channel 24 with an outlet opening 23 the fuel flows under high pressure from the high-pressure working space 29 out again. The inlet valve 19 , z. B. a check valve is designed to the effect that only fuel in the working space 29 can flow in and the exhaust valve 20 , z. B. a check valve, is designed such that only fuel from the working space 29 can flow out. The volume of the high pressure workspace 29 is due to an oscillating stroke movement of the piston 5 changed. The piston 5 rests indirectly on the drive shaft 2 from. At the end of the piston 5 or pump piston 5 is a roller shoe 9 with a roller 10 attached. The roller 10 can perform a rotational movement, the axis of rotation 25 in the drawing plane according to 1 lies and perpendicular to the plane of 2 stands. The drive shaft 2 with at least two cams 3 has a wave rolling surface 4 and the roller 10 a roller rolling surface 11 on.

The roller tread 11 the roller 10 rolls on the wave rolling surface 4 as a contact surface 12 the drive shaft 2 with the two cams 3 from. The roller shoe 9 is in one of the high pressure pump housing 8th formed roller shoe storage stored as a plain bearing. A feather 27 or spiral spring 27 as an elastic element 28 between the high pressure pump housing 8th and the roller shoe 9 is clamped, brings on the roller shoe 9 a compressive force on, leaving the roller rolling surface 11 the roller 10 in constant contact with the shaft rolling surface 4 the drive shaft 2 stands. The roller shoe 9 and the piston 5 thus jointly carry out an oscillating lifting movement. The roller 10 is with a sliding bearing 13 in the roller shoe 9 stored.

In 3 is a highly schematic representation of a high-pressure injection system 36 for the motor vehicle (not shown) shown with a high-pressure rail 30 or a fuel rail 31 , From the high-pressure rail 30 or a fuel rail 31 the fuel by means of valves (not shown) in the combustion chamber of the internal combustion engine 39 injected. An electric feed pump 35 Promotes fuel from a fuel tank 32 through a first fuel line 33a to the inlet duct 22 and through a second fuel line 33b to a lubrication room 40 ( 4 ) of the high pressure pump 1 , The high pressure pump 1 is doing from the drive shaft 2 driven and the drive shaft 2 is with a wave, z. B. a crankshaft or camshaft, the engine 39 coupled. The delivery rate of the electric prefeed pump 35 is controllable and / or controllable, so that thereby to the inlet duct 22 subsidized amount of fuel can be controlled and / or regulated. The high pressure rail 30 serves to transport the fuel into the combustion chamber of the internal combustion engine 39 inject. The from the high pressure pump 1 Unnecessary fuel is through an optional fuel return line 34 back in the fuel tank 32 returned.

4 shows a part of the high-pressure injection system 36 , Within the High-pressure pump housing 8th the high pressure pump 1 is the lubrication room 40 educated. In the lubrication room 40 are the drive shaft 2 , the roller 10 , the roller shoe 9 (not in 4 shown) and partially the piston 5 arranged. Through the through the lubricating space 40 Guided fuel will be these components 2 . 5 . 9 and 10 lubricated by the fuel. The through the second fuel line 33b in the lubrication room 40 Fuel introduced is through the fuel return line 34 from the lubricating space 40 discharged from the fuel tank 32 fed again ( 4 ). In 4 is that in 3 illustrated high-pressure injection system 36 in more detail without the high pressure rail 30 and without the internal combustion engine 39 shown. The from the pre-feed pump 35 from the fuel tank 32 sucked fuel is from the pre-feed pump 35 with a prefeed pressure, z. B. 4 bar, through the first fuel line 33a the inlet channel 22 the high pressure pump 1 fed. Furthermore, that of the prefeed pump 35 subsidized fuel during operation of the internal combustion engine 39 through the second fuel line 33b the lubricating space 40 supplied for lubrication, z. B. the drive shaft 2 , the roller 10 and the piston 5 , After flowing through the fuel through the lubricating space 40 the fuel is returned through the fuel return line 34 the fuel tank 32 fed. This allows these components 2 . 5 . 9 and 10 lubricated as well as cooled. The pre-feed pump 35 promotes in addition to the flow rate for the high-pressure pump 1 Fuel also an additional amount of fuel for lubrication of the high-pressure pump 1 that is, the fuel that passes through the lubricating space 40 flows.

The electric prefeed pump 35 has an electric motor 17 and a rotary piston pump 16 namely a gear pump 14 that is an internal gear pump 15 or gerotor pump 15 on ( 5 to 8th ). Here is the electric motor 17 the gerotor pump 15 in the gerotor pump 15 integrated. The high pressure pump 1 promotes fuel under high pressure, for example, a pressure of 1000, 3000 or 4000 bar, through a high pressure fuel line to a high pressure rail 30 , From the high-pressure rail 30 the fuel is at high pressure from an injector a combustion chamber (not shown) of the internal combustion engine 39 fed. The electric motor 17 ( 5 ) of the electrical feed pump 35 is operated with three-phase current or alternating current and is controllable in the power and thus in the speed and / or regulated. The three-phase current or alternating current for the electric motor 17 is powered by power electronics 75 from a DC voltage network of a vehicle electrical system of a motor vehicle (not shown) provided. The electric prefeed pump 35 is thus an electronically commutated feed pump 35 ,

The electric prefeed pump 35 or gerotor pump 15 has a housing 42 as a rotary piston pump housing 42 with a cup-shaped first housing component 44 as a housing pot 44 and a plate-shaped second housing component 43 as a housing cover 43 on ( 6 and 8th ). Inside the case 42 the pre-feed pump 35 is the gerotor pump 15 as internal gear pump 15 or gear pump 14 and the electric motor 17 arranged. The electric motor 17 has a stator 47 with windings 48 as electromagnets 49 and a soft iron core 70 as a soft magnetic core 68 that as a laminated core 69 is trained on. Inside the stator 47 is the gerotor pump 15 as internal gear pump 15 with an internal gear 56 with an internal toothed ring 57 and an external gear 58 with an external tooth ring 59 positioned. The internal and external gear 56 . 58 makes a gear 54 and an impeller 52 and the inner and outer teeth ring 57 . 59 have teeth 55 as conveying elements 53 on. Between the inner and outer gear 56 . 58 a working room is formed 62 out. In the external gear 58 are permanent magnets 51 fitted so that the external gear 58 also a rotor 50 of the electric motor 17 forms. The electric motor 17 is thus in the gerotor pump 15 integrated or vice versa. The electromagnets 49 of the stator 47 are alternately energized, so that due to the contact with the electromagnet 49 resulting magnetic field of the rotor 50 or the external gear 58 in a rotational movement about a rotation axis 61 is offset and due to the combing of the teeth 55 of the external gear 58 with the teeth 55 of the internal gear 56 also the internal gear 56 performs a rotational movement.

The first housing component 44 and a bearing neck 78 on the second housing component 43 serves as a thrust bearing or sliding bearing for the inner or outer gear 56 . 58 , In addition, the first housing component 44 and the second housing component 43 three holes each 71 on, in which screws for screw connections 81 as fasteners 76 for screwing together the first housing component 44 and the second housing component 43 are positioned using a workspace seal 80 the first housing component 44 and the second housing component 43 fluid-tight under bias to each other to seal the working space 62 , The annular working space seal 80 is in an annular sealing groove 79 on the second housing component 43 arranged.

In 7 is the cross section of the internal gear 56 and the external gear 58 the gerotor pump 15 shown. Between the internal gear 56 and the external gear 58 the working space is formed 62 the internal gear pump 15 out. Will the inner and outer gear 56 . 58 against the Turned clockwise, with the inner and outer gears 56 . 58 Are mounted eccentrically to each other, forms on the inner and outer gear 56 . 58 that is, between the inner and outer gears 56 . 58 , the workspace 62 out. At an angle range 73 of 180 ° forms a Zuströmarbeitsraum 63 from, at which the working space 62 increases and thereby a suction side of the internal gear pump 15 is present. At an angle range 74 of the workroom 62 arises the Abströmarbeitsraum 64 in which the working space 62 reduced and thereby a pressure side of the internal gear pump 15 arises. Into the inflow workspace 63 an inflow channel opens 65 as a suction kidney 84 , which on the second housing component 43 of the housing 42 the internal gear pump 15 is trained. The suckling kidney 84 has an angular range of less than 180 °. In the downstream workspace 64 opens a discharge channel 66 as a pressure kidney 85 , The inflow channel 65 as a suction kidney 84 and the discharge channel 66 as a pressure kidney 85 are in 7 each shown in dashed lines. The through the outflow channel 66 Guided fuel is through the first fuel line 33a the inlet valve 19 the high pressure pump 1 supplied and through the second fuel line 33b the lubricating space 40 supplied ( 4 ).

In 8th is a cross section of the internal gear pump 15 or gerotor pump 15 shown in a first embodiment. At the substantially plate-shaped first housing component 44 are the inflow channel 65 and the discharge channel 66 educated. An end region of the inflow channel 65 forms a kidney-shaped opening as Saugniere 84 in the inflow workspace 63 and one end of the outflow channel 66 flows as a pressure kidney 85 in the downstream workspace 64 , In the holes 71 screws are arranged so that thereby the plate-shaped second housing component 43 detachable with the cup-shaped first housing component 44 is connected, that is screwed 81 between the first and second housing components 44 . 43 are formed. The two housing components 43 . 44 limit the work space 62 , inside which the internal gear 56 and the external gear 58 are arranged. The rotation axis 61 of the internal gear 56 is shown, but the axis of rotation of the external gear is 58 not shown and the axis of rotation of the external gear 58 is parallel with a distance to the rotation axis 61 of the internal gear 56 aligned, that is the inner and outer gear 56 . 58 are aligned eccentrically to each other.

The internal and external gear 56 . 58 are by means of a sliding bearing on the two housing components 43 . 44 stored. In the axial direction, that is in the direction of the axis of rotation 61 is in a first axial direction 67 the inner and outer gear 56 . 58 on first housing component 44 plain bearing. In a second axial direction 72 perpendicular to the first axial direction 67 aligned, are the wheels 52 as the inner and outer gear 56 . 58 on the second housing component 43 , ie on the bearing neck 78 the second housing component 43 stored.

The radial orientation of the internal gear 56 and the external gear 58 to each other, that is the distance between the axis of rotation 61 of the internal gear 56 and the rotation axis of the external gear 58 as the eccentricity between the inner and outer gear 56 . 58 , is determined by a first radial bearing geometry and a second radial bearing geometry. The first radial bearing geometry is called the bearing neck 78 on the second housing component 44 formed and the second radial bearing geometry is as an annular bearing stage 46 on the bearing neck 78 educated. The bearing neck 78 is within a bearing bore 77 on the internal gear 56 arranged. The bearing bore 77 is any recess, for example, formed as a blind or through hole. On the external gear 56 is an annular bearing recess 60 formed and in the region of the annular bearing recess 60 is the external gear 58 on the second radial bearing geometry as the bearing stage 46 on. With the two radial bearing geometries are thus the inner and outer gear 56 . 58 in the radial direction perpendicular to the axis of rotation 61 radially mounted. The axial and / or radial sliding bearings on the first housing component 44 and the second housing component 43 are preferably provided with a corresponding coating or plating, for example made of brass or a plastic suitable for sliding bearing, for example PTFE.

The first pot-shaped housing component 44 is in two parts with an inner first part housing component 82 and an outer first part housing component 83 , The terms inner and outer first part housing component 82 . 83 refer to a radial direction 41 perpendicular to the axis of rotation 61 , Between the inner first part housing component 82 and the outer first part housing component 83 is in the radial direction 41 as well as in the axial direction 67 . 72 a room 37 as an annulus 38 limited. The space 37 for receiving the stator 47 is thus exclusively of the first pot-shaped housing component 44 limited. The inner first part housing component 82 is formed of aluminum and the outer first part housing component 83 made of plastic. The inner first part housing component 82 includes a thrust bearing plate 86 , a partition 18 and a wall 88 , The thrust bearing plate 86 is disc-shaped and the gears 54 or the work space 62 facing side of the thrust bearing plate 86 serves as a thrust bearing for the gears 54 , Opposite to this axial bearing on the thrust bearing plate 86 is on the thrust bearing plate 86 a ribbing 87 educated. The ribbing 87 serves on the one hand for static stiffening of the thrust bearing plate 86 and on the other hand to increase the surface area on the outside of the rotary piston pump 16 so that due to the ribbing 87 during operation of the rotary piston pump 16 occurring heat can be better dissipated to the environment. The dividing wall 18 is partially cylindrical jacket-shaped and ring-shaped and is substantially in accordance with the section in FIG 8th in an axial direction 67 . 72 aligned. The wall 88 is annular and substantially in the radial direction 41 aligned and lies on the second housing component 43 on. Between the wall 88 the inner first part housing component 82 and the second housing component 43 is the annular working space seal 80 under a bias on.

The outer first part housing component 83 includes an outer partition 89 which are in the radial direction 41 the room 37 seals to the outside. The outer first part housing component 83 also includes a first wall 90 and a second wall 91 , The outer partition 89 is with a first wall 90 connected and the first wall 90 is annular as well as in the radial direction 41 aligned. The first wall 90 is on the wall 88 in the axial direction 67 . 72 due to the attachment with the fasteners 76 on. At the outer partition 89 is also the second wall 91 the outer first part housing component 83 educated. The second wall 91 is also annular and in the radial direction 41 aligned. The second wall 91 has a circular opening, within which the ribbing 87 is arranged. Between the radially inner end of the second wall 91 and the ribbing 87 is a stator seal 92 For example, a labyrinth seal 92 arranged. Also, between the inner first part housing component 82 that is the wall 88 and the outer first part housing component 83 that is the first wall 90 , another stator seal 92 available. The two stator seals 92 serve the space 37 on the stator 47 with respect to the environment. It occurs at the room 37 the same or substantially the same pressure as in the environment, thereby thereby with respect to the tightness of the stator seals 92 much lower requirements exist than in the workspace seal 80 , In the workroom 62 For example, pressures of 9 to 10 bar occur, thereby creating a pressure difference between the working space 62 and the environment by means of the working space seal 80 of about 9 bar is to seal. A cutting plane 45 is perpendicular to the axis of rotation 61 aligned and also in the axial direction 67 . 72 centrally between the axial ends of a gear 54 arranged. The cutting plane 45 cuts through the dividing wall 18 and the outer partition 89 as well as the stator 47 , The workspace seal 80 serves for the exclusive sealing of the working space 62 to the environment and not to the sealing of the work space 62 to the room 37 on the stator 47 , The workspace seal 80 is from the cutting plane 45 not cut. Due to the structural design of the first and second housing components 43 . 44 introduces leakage of leakage fuel to the workspace seal 80 not to the entry of the leakage fuel into the room 37 , but only for deriving the leakage fuel into the environment. The workspace seal 80 is therefore not on the cutting plane due to these constructive advantages 45 cut. The second housing component 43 is made of metal, such as steel and / or aluminum, and / or plastic. The inner first part housing component 82 is made of metal and / or plastic and the outer first part housing component 83 is made of metal, such as steel and / or aluminum, and / or plastic.

In 9 is a second embodiment of the rotary piston pump 16 shown. In the following, essentially only the differences from the first embodiment will be according to FIG 8th described. The second wall 91 the outer first part housing component 83 has no circular opening, but is closed, so that no ribbing 87 on the inner first part housing component 82 is trained. In addition, there is no stator seal 92 between the non-existing ribbing 87 and the second wall 91 the outer first part housing component 83 necessary, because on the second wall 91 no circular opening is formed. The second wall 91 lies on the thrust bearing plate 86 on.

Overall, considered with the rotary piston pump according to the invention 16 and the high-pressure injection system according to the invention 36 significant benefits. A leak or leakage on the workspace seal 80 leads to the exclusive derivation of the leakage fuel in the environment, because the leakage fuel from the partition 18 and the wall 88 is derived by design into the environment and no direct flow of the fluid as the fuel from the working space 62 in the room 37 is executable without the fluid gets to the environment. A leakage at the workspace seal 80 thus does not lead to the introduction of fuel to the stator 47 with the electromagnets 49 which greatly increased due to the operation Have temperature. This can cause major damage to the rotary piston pump 16 in case of leakage of the working space seal 80 be avoided. The second plate-shaped housing component 43 essentially relates to the hydraulic part or the hydraulic function of the rotary piston pump 16 and the first pot-shaped housing component 44 essentially relates to the electrical or electromagnetic part or function of the rotary piston pump 16 , The first and second housing components 43 . 44 As a result, they can also be initially produced at separate locations in different production plants and then connected to one another to form the rotary piston pump 16 , At the partition 18 as the inner partition 18 for fluid-tight sealing and separation in the radial direction 41 of the workroom 62 concerning the room 37 with the stator 47 can on its radial outside, that is on its outside to the room 37 , Also stiffening ribs (not shown) may be formed. These stiffening ribs are used for static stiffening of the partition wall 18 and can be in the spaces between each electromagnet 49 be arranged.

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 3624532 C2 [0004]
• DE 3406349 A1 [0005]
• DE 29913367 U1 [0006]

Claims (15)

Rotary piston pump ( 16 ) for conveying a fluid, in particular fuel, comprising - at least two wheels ( 52 ) with conveying elements ( 53 ), of which each have a rotation axis ( 61 ) a rotational movement is executable, - one of the at least two wheels ( 52 ) existing work space ( 62 ) for passing the fluid through the working space ( 62 ), - an electric motor ( 17 ) with a stator ( 47 ) and a rotor ( 50 ), - a sealing element for sealing the working space ( 62 ) from the stator ( 47 ), - a multi-part housing ( 42 ) with a first housing component ( 44 ) and a second housing component ( 43 ), characterized in that the first housing component ( 44 ) also as the sealing element ( 18 ) for sealing the working space ( 62 ) from the stator ( 47 ) acts in such a way that in the case of a leakage at the working space ( 62 ), the leakage fluid, in particular exclusively, enters the environment and preferably no leakage fluid reaches the stator. Rotary piston pump according to claim 1, characterized in that the first housing component ( 44 ), in particular exclusively the first housing component ( 44 ), a room ( 37 ), in particular annular space ( 38 ), and within the space ( 37 ) the stator ( 47 ) and / or the first housing component ( 44 ) a partition wall ( 18 ) as a sealing element ( 18 ) for sealing the working space ( 62 ) from the stator ( 47 ). Rotary piston pump according to claim 2, characterized in that the partition wall ( 18 ) in the radial direction, in particular exclusively, the working space ( 62 ) from the stator ( 47 ) separates fluid-tight. Rotary piston pump according to one or more of the preceding claims, characterized in that the first housing component ( 44 ) is formed in two parts with a, in particular in the radial direction, inner first part housing component ( 82 ) and one, in particular in the radial direction, outer first part housing component ( 83 ) and preferably the inner first part housing component ( 82 ) acts in such a way that in the case of a leakage at the working space ( 62 ), the leakage fluid, in particular exclusively, enters the environment and preferably no leakage fluid reaches the stator. Rotary piston pump according to one or more of the preceding claims, characterized in that the space ( 37 ) with the stator ( 47 ) radially between the inner first part housing component ( 82 ) and the outer first part housing component ( 83 ) and / or the space ( 37 ) with the stator ( 47 ) exclusively from the first housing component ( 44 ) is limited. Rotary piston pump according to one or more of the preceding claims, characterized in that the first housing component ( 44 ) is substantially pot-shaped and the second housing component ( 43 ) is formed substantially lid-shaped. Rotary piston pump according to one or more of the preceding claims, characterized in that radially outside the at least two wheels ( 52 ) the walls ( 18 . 89 ) of the first housing component ( 44 ) are formed and preferably no wall of the second housing component ( 43 ) is trained. Rotary piston pump according to one or more of the preceding claims, characterized in that the first housing component ( 44 ) with the second housing component ( 43 ) with at least one fastening element ( 76 ), in particular a screw connection ( 81 ), preferably releasably connected to one another and / or between the first housing component ( 44 ) and the second housing component ( 43 ) a workspace seal ( 80 ), in particular O-ring seal ( 80 ), for fluid-tight sealing of the working space ( 62 ) is arranged with respect to the environment. Rotary piston pump according to one or more of the preceding claims, characterized in that the working space seal ( 80 ) between the first housing component ( 44 ) and second housing component ( 43 ) is arranged such that in case of leakage of the working space seal ( 80 ) on the working space seal ( 80 ) escaping leakage fluid into the environment, in particular exclusively into the environment, and preferably does not reach the leakage fluid to the stator ( 47 ) and / or one perpendicular to a rotation axis ( 61 ) of an impeller ( 52 ), in particular gear ( 54 ), aligned cutting plane ( 45 ), which in the axial direction centrally between the two axial ends of the impeller ( 52 ), the dividing wall ( 18 ) and / or the working space seal ( 80 ) does not cut. Rotary piston pump according to one or more of the preceding claims, characterized in that the rotary piston pump ( 16 ) a bearing neck ( 78 ) for the radial mounting of the at least two wheels ( 52 ) and the bearing neck ( 78 ) on the second housing component ( 43 ), in particular in one piece on the second housing component ( 43 ), is trained. Rotary piston pump according to one or more of the preceding claims, characterized in that the at least two wheels ( 52 ) axially on the first housing component ( 44 ) and / or on the second housing component ( 43 ) are stored and / or the at least two wheels ( 52 ) axially on the bearing neck ( 78 ) are stored. Rotary piston pump according to one or more of claims 4 to 11, characterized in that the outer first part housing component ( 83 ) at least one outer partition wall ( 89 ) for the radial fluid-tight separation of the space ( 37 ) on the stator ( 47 ) to the environment and / or between inner first part housing component ( 82 ) and the outer first part housing component ( 83 ) at least one stator seal ( 92 ), in particular labyrinth seal ( 92 ), for fluid-tight sealing of the room ( 37 ) on the stator ( 47 ) is formed with respect to the environment. Rotary piston pump according to one or more of the preceding claims, characterized in that the conveying elements ( 53 ) Teeth ( 55 ) of a gear ( 54 ) and / or the rotary piston pump ( 16 ) a gear pump ( 14 ), preferably internal gear pump ( 15 ), in particular gerotor pump ( 15 ) is. Rotary piston pump according to one or more of the preceding claims, characterized in that the electric motor ( 17 ) in the rotary piston pump ( 16 ) is integrated by a rotor ( 50 ) of the electric motor ( 17 ) an impeller ( 52 ), in particular permanent magnets ( 51 ) in an impeller ( 52 ) are installed so that the impeller ( 52 ) with the permanent magnets ( 51 ) the rotor ( 50 ) and / or the delivery rate of the rotary piston pump ( 16 ), preferably with integrated electric motor ( 17 ), controllable and / or controllable, in particular by the power and / or speed of the electric motor ( 17 ) is controllable and / or controllable. High-pressure injection system ( 36 ) for an internal combustion engine ( 39 ), comprising - a high-pressure pump ( 1 ), - a high-pressure rail ( 30 ), - a prefeed pump ( 35 ) for conveying a fuel from a fuel tank ( 32 ) through a fuel line ( 33a ) to the high pressure pump ( 1 ), characterized in that the prefeed pump is designed according to one or more of the preceding claims.

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