DE102021134046A1 - Drive train of a hybrid or all-electric motor vehicle - Google Patents

Abstract

The invention relates to a drive train (1) of a hybrid or all-electric motor vehicle (2) comprising an electric machine (3) driving the motor vehicle (2) and a torsional vibration damper (4), the electric machine (3) having a rotor (5). whose axis of rotation (6) is arranged coaxially to the axis of rotation (7) of the torsional vibration damper (4) in the drive train (1), and the rotor (5) is non-rotatably connected to a pot-like rotor carrier (8), within which the torsional vibration damper (4) is positioned is, wherein a magnetic field (9) acts on the torsional vibration damper (4), which is designed in such a way that ferromagnetic particles (10) can be immobilized in and/or on the torsional vibration damper (4).

Description

The present invention relates to a drive train of a hybrid or fully electrically operable motor vehicle comprising an electric machine driving the motor vehicle and a torsional vibration damper, the electric machine having a rotor whose axis of rotation is arranged coaxially to the axis of rotation of the torsional vibration damper in the drive train, and the rotor is non-rotatably connected to a pot-shaped Rotor carrier is connected, within which the torsional vibration damper is positioned.

A drive train of a hybrid vehicle includes a combination of an internal combustion engine and an electric motor, and allows - for example in urban areas - a purely electric mode of operation with simultaneous sufficient range and availability, especially for cross-country trips. In addition, there is the possibility, in certain operating situations, to be driven simultaneously by the internal combustion engine and the electric motor.

How from the EP0773127A1 , DE10018926A1 and US2007/0175726A1 is known, a first clutch arrangement can be arranged between the internal combustion engine and the electric motor in order to separate the internal combustion engine from the electric motor and the remaining drive train of the hybrid vehicle. When driving purely electrically, the first clutch arrangement is then opened and the internal combustion engine is switched off, so that the output torque of the hybrid vehicle is applied solely by the electric motor.

Torsional vibration dampers are often used in the drive train in order to optimize smooth running in hybrid drive trains in motor vehicles. Torsional vibration dampers are known in principle for damping torsional vibrations of a drive shaft of a motor vehicle engine. For example, from the DE 10 2008 004 70 A1 a dual-mass flywheel is known in which, for torsional vibration damping of a crankshaft of an internal combustion engine, a primary flywheel is coupled via an arc spring to a secondary flywheel that can be rotated relative to the primary flywheel. The arc spring is arranged in an arc spring channel, with a channel wall of the arc spring channel being formed by the primary flywheel. A flange of the secondary flywheel protrudes into the arc spring channel and is supported on the channel wall by a friction ring.

Another torsional vibration damper is, for example, from the publication WO14094761A1 known. The torsional vibration damper disclosed there has an input part and an output part which can be rotated to a limited extent against the action of a spring device made up of arc springs distributed over the circumference and which has a retaining shell for the arc springs under the action of centrifugal force. The loading means on the output side of the output part are formed from driver elements which are exposed from the output part.

When using metal springs for a torsion damper, abrasion of the springs cannot be ruled out. There is also a certain amount of residual dirt from the assembly/manufacturing of the components. This dirt/abrasion must not get on the windings or on the magnets of the rotor in the area of the air gap or on the lateral flat surfaces.

For this reason, torsional vibration dampers have not been used as wet retainers under, next to and/or in the vicinity of electric machines, since the abrasion caused by the oil exchange can reach sensitive components such as the magnets, windings or sensors of the electric machine and damage them or limit their function.

It is therefore the object of the invention to avoid or at least mitigate these disadvantages and to provide a particularly reliable and durable drive train of a hybrid or fully electric motor vehicle.

This object is achieved by a drive train of a hybrid or all-electric motor vehicle comprising an electric machine driving the motor vehicle and a torsional vibration damper, the electric machine having a rotor whose axis of rotation is arranged coaxially to the axis of rotation of the torsional vibration damper in the drive train, and the rotor is non-rotatably connected to a pot-like rotor carrier is connected, within which the torsional vibration damper is positioned, wherein a magnetic field acts on the torsional vibration damper, which is designed such that ferromagnetic particles are immobilized in and / or on the torsional vibration damper.

This has the advantage that the immobilization of the ferromagnetic particles, which can occur, for example, due to abrasion of components of the torsional vibration damper rubbing against one another, can prevent premature wear or even failure of the electrical machine. For this purpose, ferromagnetic particles, such as metallic dirt and abrasion, are fixed inside or on the torsional vibration damper by magnetic force.

The torsional vibration damper is particularly preferably a wet torsional vibration damper that is operated within a wet room. Since neither an oil exchange nor abrasion can be prevented here, the ferromagnetic particle abrasion must be prevented from reaching the critical components. If this is not possible with a completely encapsulated oil flow, the open oil flow must be freed from abrasion. This applies above all to operation at low speed, when strong centrifugal forces are at work that drive the oil radially outwards.

For this purpose, according to the invention, targeted magnetism is proposed at locations that are otherwise not relevant to the function, i.e., for example, on the retainer shell at locations where the spring is not seated on the retainer. Here, for example, the retainer edge or, in the case of the so-called roof retainer, the roof of the retainer can be used. Here, either individual magnets can be inserted / attached or, particularly preferably, the retainer material itself can be magnetized at the selected point, which is particularly cost-effective and functionally reliable and would result in a more homogeneous magnetic field. The retainer edge would have the advantage here that, in addition to the magnetic adhesion of the metal particles, these are driven radially outwards into the retainer by the centrifugal force and thus there is a reinforcing effect that prevents the metal particles from escaping the retainer

In addition to this, a circumferential filtration structure can be provided at the end of the retainer, which can be clipped into a groove of the retainer, for example. Here, the metal abrasion can also be securely enclosed in the pores instead of just on the surface. This helps, e.g. when parking the vehicle, so that the dirt trapped under speed is not washed out of the retainer again. A distinction can be made between two variants of the filter element: The filter material can be made non-magnetic from any suitable filter material. The advantage here is the optimal choice of material without influencing e.g. the magnetic flux of an electric machine, sensor, etc. Alternatively, the filter structure could also consist of a magnetizable material, e.g. an open-pored, magnetic metal foam, whereby ferromagnetic dirt particles can be immobilized even more securely.

First, the individual elements of the claimed subject matter of the invention are explained in the order in which they are mentioned in the set of claims, and particularly preferred configurations of the subject matter of the invention are described below.

For the purposes of this application, the drive train of a motor vehicle is understood to mean all components that generate the power for driving the motor vehicle in the motor vehicle and transmit it to the road via the vehicle wheels. For the purposes of this application, motor vehicles are land vehicles that are moved by machine power without being tied to railroad tracks. A motor vehicle can be selected, for example, from the group of passenger cars (cars), trucks (lorries), mopeds, light motor vehicles, motorcycles, buses (COM) or tractors. A hybrid electric vehicle, also referred to as a hybrid electric vehicle (HEV), is an electric vehicle that is powered by at least one electric motor and another energy converter and draws energy from both its electrical storage device (battery) and additional fuel that is carried along.

A torsional vibration damper in the drive train according to the invention can in particular have the task of damping vibrations between an engine, such as an internal combustion engine or an electric machine, and, for example, a transmission within a drive train. Combustion engines in particular do not deliver constant torque. The constantly changing angular speeds of the crankshaft generate vibrations that can be transmitted to the vehicle transmission via the clutch system and the transmission input shaft. Here, these vibrations can cause unwanted rattling noises. Torsional vibration dampers are designed to reduce these vibrations between the engine and transmission.

The torsional vibration damper can be designed in particular as a dual-mass flywheel. A torque transmission device embodied as a dual-mass flywheel can in particular comprise a primary flywheel embodied as a primary part, a secondary flywheel embodied as a secondary part, a rotary plain bearing, one or more spring devices and possibly one or more damper devices. With a dual mass flywheel (DMF), the flywheel mass is divided into the primary flywheel mass (primary flywheel) and the secondary flywheel mass (secondary flywheel). A spring device is arranged in the flow of torque between the primary flywheel and the secondary flywheel, which spring device connects the primary flywheel and the secondary flywheel with one another in a torsionally soft manner.

According to a further particularly preferred embodiment of the invention, it can be provided that the spring device is designed as an arc spring. The spring device can in particular which also comprise at least one arc spring and/or at least one compression spring. The spring device can also be formed from a plurality of spring devices acting in parallel and/or in series.

To dampen the torsion between the primary flywheel and the secondary flywheel, a damping device, for example in the form of a friction clutch, can preferably be arranged in the torque flow between the primary flywheel and the secondary flywheel.

The function of the primary flywheel is to couple the drive side of the dual-mass flywheel to the spring device. The primary flywheel can, in particular, be made in several parts and can include a primary flywheel disk, which can be connected to a primary wheel hub, in particular via a primary connecting disk. The primary flywheel and the primary connecting disk can preferably be connected to one another in a torque-proof manner by means of riveted connections. The primary flywheel is preferably made of a metallic material.

The secondary flywheel has the function of coupling the output side of the torsional vibration damper to the spring device. The secondary flywheel can, in particular, be made in several parts and can include a secondary flywheel disk, which can be connected to a secondary wheel hub, in particular via a secondary connecting disk. The secondary flywheel and the secondary connecting disk can preferably be connected to one another in a torque-proof manner by means of riveted connections. The secondary flywheel is preferably made of a metallic material.

The primary flywheel can in particular have a receptacle for the spring device. The receptacle, in particular for an arc spring, is preferably arranged in the form of a channel in the primary flywheel. It is particularly preferred that the receptacle for the spring device is formed monolithically with the primary flywheel. Such a receptacle is also referred to as a retainer or spring retainer.

The torsional vibration damper is intended in particular for use in an all-electric or hybrid drive train of a motor vehicle.

It is particularly preferred to use the torsional vibration damper in a hybrid module. In a hybrid module, structural and functional elements of a hybridized drive train can be spatially and/or structurally combined and preconfigured, so that a hybrid module can be integrated in a particularly simple manner into a drive train of a motor vehicle. In particular, an electric motor and a clutch system, in particular with a separating clutch for coupling the electric motor into and/or decoupling the electric motor from the drive train, can be present in a hybrid module.

• P0: der Elektromotor ist vor der Brennkraftmaschine angeordnet und beispielsweise über einen Riemen mit der Brennkraftmaschine gekoppelt. Bei dieser Anordnung des Elektromotors wird dieser auch gelegentlich als Riemenstartergenerator (RSG) bezeichnet,
• P1: der Elektromotor ist direkt hinter der Brennkraftmaschine angeordnet. Die Anordnung des Elektromotors kann beispielsweise kurbelwellenfest vor der Anfahrkupplung erfolgen,
• P2: der Elektromotor ist zwischen einer häufig als K0 bezeichneten Trennkupplung und der Anfahrkupplung aber vor dem Fahrzeuggetriebe im Antriebsstrang angeordnet,
• P3: der Elektromotor ist im Fahrzeuggetriebe und/oder der Getriebeausgangswelle angeordnet,
• P4: der Elektromotor ist an einer bestehenden oder separaten Fahrzeugachse angeordnet und
• P5: der Elektromotor ist am oder im Fahrzeugrad angeordnet, beispielsweise als Radnabenmotor.

A hybrid module can be divided into the following categories P0-P4 depending on the point of intervention of the electric motor in the drive train:

• P0: the electric motor is arranged in front of the internal combustion engine and is coupled to the internal combustion engine via a belt, for example. With this arrangement of the electric motor, it is also sometimes referred to as a belt starter generator (RSG),
• P1: the electric motor is located directly behind the internal combustion engine. The electric motor can be arranged, for example, on the crankshaft in front of the starting clutch,
• P2: the electric motor is located between a separating clutch, often referred to as K0, and the starting clutch, but in front of the vehicle transmission in the drive train,
• P3: the electric motor is arranged in the vehicle transmission and/or the transmission output shaft,
• P4: the electric motor is arranged on an existing or separate vehicle axle and
• P5: the electric motor is arranged on or in the vehicle wheel, for example as a wheel hub motor.

According to an advantageous embodiment of the invention, it can be provided that the magnetic field is caused by permanent magnets arranged in the rotor.

According to a further preferred further development of the invention, it can also be provided that the magnetic field is caused by at least one permanent magnet arranged in and/or on the torsional vibration damper.

Furthermore, it can be provided according to a likewise advantageous embodiment of the invention that the permanent magnet is designed as a magnetized component of the torsional vibration damper.

According to a further particularly preferred embodiment of the invention, it can be provided that in the direction of the magnetic field and/or in the direction of hydraulic flow a ferro suspension containing magnetic particles, a filter element is arranged.

Furthermore, the invention can also be further developed in such a way that the torsional vibration damper has a spring element which rests at least in sections on a spring retainer in the radially outer and axial direction on both sides.

In a likewise preferred embodiment variant of the invention, it can also be provided that the spring retainer is designed as a one-piece or multi-piece roof retainer.

It can also be advantageous to further develop the invention in such a way that the ferromagnetic particles can be immobilized on a surface of the rotor carrier pointing radially inwards.

According to a further preferred embodiment of the subject matter of the invention, it can be provided that the inward-facing surface comprises a recess and/or an embossing.

Finally, the invention can also be implemented in an advantageous manner in that the permanent magnet is designed as a section of a spring retainer formed from sheet metal.

The invention will be explained in more detail below with reference to figures without restricting the general inventive idea.

• 1 einen Antriebsstrang eines Kraftfahrzeugs mit einer elektrischen Maschine und einem Drehschwingungsdämpfer in einer schematischen Axialschnittansicht,
• 2 einen Antriebsstrang eines Kraftfahrzeugs mit einer elektrischen Maschine und einem Drehschwingungsdämpfer in einer schematischen Querschnittansicht,
• 3 eine erste Ausführungsform eines Antriebsstrangs eines Kraftfahrzeugs mit einer elektrischen Maschine und einem Drehschwingungsdämpfer in einer schematischen Axialschnittansicht,
• 4 eine zweite Ausführungsform eines Antriebsstrangs eines Kraftfahrzeugs mit einer elektrischen Maschine und einem Drehschwingungsdämpfer in einer schematischen Axialschnittansicht,
• 5 eine dritte Ausführungsform eines Antriebsstrangs eines Kraftfahrzeugs mit einer elektrischen Maschine und einem Drehschwingungsdämpfer in einer schematischen Axialschnittansicht,
• 6 eine vierte Ausführungsform eines Antriebsstrangs eines Kraftfahrzeugs mit einer elektrischen Maschine und einem Drehschwingungsdämpfer in einer schematischen Axialschnittansicht,
• 7 eine fünfte Ausführungsform eines Antriebsstrangs eines Kraftfahrzeugs mit einer elektrischen Maschine und einem Drehschwingungsdämpfer in einer schematischen Axialschnittansicht,
• 8 eine sechste Ausführungsform eines Antriebsstrangs eines Kraftfahrzeugs mit einer elektrischen Maschine und einem Drehschwingungsdämpfer in einer schematischen Axialschnittansicht,
• 9 ein Kraftfahrzeug mit einer elektrischen Maschine und einem Drehschwingungsdämpfer in einer schematischen Blockschaltansicht.

It shows:

• 1 a drive train of a motor vehicle with an electric machine and a torsional vibration damper in a schematic axial sectional view,
• 2 a drive train of a motor vehicle with an electric machine and a torsional vibration damper in a schematic cross-sectional view,
• 3 a first embodiment of a drive train of a motor vehicle with an electric machine and a torsional vibration damper in a schematic axial sectional view,
• 4 a second embodiment of a drive train of a motor vehicle with an electric machine and a torsional vibration damper in a schematic axial sectional view,
• 5 a third embodiment of a drive train of a motor vehicle with an electric machine and a torsional vibration damper in a schematic axial sectional view,
• 6 a fourth embodiment of a drive train of a motor vehicle with an electric machine and a torsional vibration damper in a schematic axial sectional view,
• 7 a fifth embodiment of a drive train of a motor vehicle with an electric machine and a torsional vibration damper in a schematic axial sectional view,
• 8th a sixth embodiment of a drive train of a motor vehicle with an electric machine and a torsional vibration damper in a schematic axial sectional view,
• 9 a motor vehicle with an electric machine and a torsional vibration damper in a schematic block diagram.

The 1 shows a drive train 1 of a hybrid or fully electrically operated motor vehicle 2, comprising an electric motor 2 driving the motor vehicle 3 and a torsional vibration damper 4, as is also the case, for example, in FIG 9 is sketched. The electric machine 3 has a rotor 5 whose axis of rotation 6 is arranged coaxially to the axis of rotation 7 of the torsional vibration damper 4 in the drive train 1 . The rotor 5 is non-rotatably connected to a pot-like rotor carrier 8, within which the torsional vibration damper 4 is positioned. A magnetic field 9 acts on the torsional vibration damper 4 and is designed in such a way that ferromagnetic particles 10 are immobilized in and/or on the torsional vibration damper 4 .

From the 2 It can be seen that the magnetic field 9 is caused by permanent magnets 11 arranged in the rotor 5 and the magnetic field 9 extends radially inwards into the torsional vibration damper 4, so that its magnetic effect can be used to immobilize the ferromagnetic particles 9.

The 1 shows a torsional vibration damper 4 arranged in a wet room inside the rotor 5. The roof retainer 15 carries the springs 14 like in a prism and nestles as close as possible to the rotor 15. The spring element 14 is thus in the radially outer and axial direction on both sides, at least in sections on a spring retainer 15. The abrasion/dirt collects under speed in the roof of the retainer 15 and can be held there by the magnetic attraction of the rotor 5 also be immobilized. As a result, the spring contact points are free from abrasion.

The embodiment of 3 shows a similar structure. Here, however, the roof of the retainer 15 is cut in the area between the springs 14 . The oil including abrasion/dirt can run off here as a suspension under speed. The oil can be accumulated in the area below the rotor 5 by means of a further metal sheet 19 which extends radially inwards and which is hung in and secured, riveted or welded in place.

The plate 19 can also be used to determine the rotational position of the rotor 5 with corresponding recesses or as a driver disk of the damper 4. Due to the accumulation of the oil, the abrasion/dirt is again magnetically secured within the rotor 5 at speed and remains trapped there even when the electric machine 3 is switched off. Also is in the 3 shown that the ferromagnetic particles 10 are immobilized on a radially inwardly facing surface 16 of the rotor carrier 8. The spring retainer 15 can be designed as a one-piece or multi-piece roof retainer.

4 shows another embodiment with a two-part damper retainer 15, here also formed as a roof retainer. In the case of compression springs, this can also be a driver disk and counter disk. The drive plate is here screwed, riveted, welded or taken along and axially secured to the rotor support 8 in a form-fitting manner. The drive plate closes the inner space for accumulating the oil and also catches the abrasion/dirt inside the rotor 5.

Another variant is in the 5 shown. Guide segments (sliding shells) for the springs 14 are inserted here as retainers. These segments are aligned via hook-in lugs. The oil including abrasion/dirt can escape to the rotor 5 in the area between the segments. The segments can be designed as a roof or classically round. 6 shows the one from the 5 known embodiment, in which the inwardly facing surface 16 comprises a recess 17 and/or an embossing 18.

The 7 it is easy to see that the magnetic field 9 can be caused by at least one permanent magnet 11 arranged in and/or on the torsional vibration damper 4 . The permanent magnet 11 is designed as a magnetized component of the torsional vibration damper 4, namely as a section of a spring retainer 15 formed from sheet metal.

In addition, a filter element 13 can also be arranged in the direction of the magnetic field and/or in the hydraulic flow direction 12 of the suspension containing ferromagnetic particles 10, as is exemplified in FIG 8th is shown.

The invention is not limited to the embodiments shown in the figures. The foregoing description is therefore not to be considered as limiting but as illustrative. The following patent claims are to be understood in such a way that a mentioned feature is present in at least one embodiment of the invention. This does not exclude the presence of other features. If the patent claims and the above description define 'first' and 'second' feature, this designation serves to distinguish between two similar features without establishing a ranking.

Reference List

1

powertrain

2

motor vehicle

3

electric machine

4

torsional vibration damper

5

rotor

6

axis of rotation

7

axis of rotation

8th

rotor carrier

9

Field

10

particles

11

permanent magnets

12

flow direction

13

filter element

14

spring element

15

spring retainer

16

surface

17

recess

18

embossing

19

sheet

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited by the applicant was 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.

Patent Literature Cited

• EP 0773127 A1 [0003]
• DE 10018926 A1 [0003]
• US 2007/0175726 A1 [0003]
• DE 10200800470 A1 [0004]
• WO 14094761 A1 [0005]

Claims (10)

Drive train (1) of a hybrid or fully electrically operated motor vehicle (2) comprising an electric machine (3) driving the motor vehicle (2) and a torsional vibration damper (4), the electric machine (3) having a rotor (5) whose axis of rotation ( 6) is arranged coaxially to the axis of rotation (7) of the torsional vibration damper (4) in the drive train (1), and the rotor (5) is non-rotatably connected to a pot-like rotor carrier (8), within which the torsional vibration damper (4) is positioned, characterized that on the torsional vibration damper (4) acts a magnetic field (9), which is designed such that ferromagnetic particles (10) in and / or on the torsional vibration damper (4) can be immobilized. Drive train (1) after claim 1 , characterized in that the magnetic field (9) is effected by permanent magnets (11) arranged in the rotor (5). Drive train (1) according to one of the preceding claims, characterized in that the magnetic field (9) is caused by at least one permanent magnet (11) arranged in and/or on the torsional vibration damper (4). Drive train (1) according to one of the preceding claims, characterized in that the permanent magnet (11) is designed as a magnetized component of the torsional vibration damper (4). Drive train (1) according to one of the preceding claims, characterized in that a filter element (13) is arranged in the direction of the magnetic field and/or in the hydraulic flow direction (12) of a suspension containing ferromagnetic particles (10). Drive train (1) according to one of the preceding claims, characterized in that the torsional vibration damper (4) has a spring element (14) which rests at least in sections on a spring retainer (15) in the radially outer and axial direction on both sides. Drive train (1) according to one of the preceding claims, characterized in that the spring retainer (15) is designed as a one-part or multi-part roof retainer. Drive train (1) according to one of the preceding claims, characterized in that the ferromagnetic particles (10) can be immobilized on a surface (16) of the rotor support (8) pointing radially inwards. Drive train (1) according to one of the preceding claims, characterized in that the inwardly pointing surface (16) comprises a recess (17) and/or an embossing (18). Drive train (1) according to one of the preceding claims, characterized in that the permanent magnet (11) is designed as a section of a spring retainer (15) formed from sheet metal.

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