DE102020130259B4 - Hydraulic device and electrically operable drive train - Google Patents

Abstract

Hydraulic device (1) for an electric drive train (2) with an electric machine (3), the hydraulic device (1) comprising a hydraulic reservoir (4) in which an electrically operable hydraulic pump (5) and at least one electrically switchable hydraulic valve (6 ) are arranged, characterized in that the hydraulic device (1) has an electrical contacting device (7) which extends through the hydraulic reservoir (4) and first electrical contacting means (8) for electrically connecting the hydraulic pump (5) to the electrical contacting device (7 ) and second electrical contacting means (9) for electrically connecting the hydraulic valve (6) to the electrical contacting device (7), and the electrical contacting device (7) further comprises a third electrical contacting means (10) which is outside or inside the hydraulic reservoir ( 4) indicated is arranged and the third electrical contact means (10) is electrically connected to the first electrical contact means (8) and the second electrical contact means (9).

Description

The present invention relates to a hydraulic device for an electric drive train with an electric machine, the hydraulic device comprising a hydraulic reservoir in which an electrically operable hydraulic pump and at least one electrically switchable hydraulic valve are arranged. The invention also relates to an electrically operable drive train with a hydraulic device.

Electric motors are increasingly being used to drive motor vehicles in order to create alternatives to internal combustion engines that require fossil fuels. Significant efforts have already been made to improve the suitability for everyday use of electric drives and also to be able to offer users the driving comfort they are accustomed to.

From the publication DE 197 46 953 A1 discloses a contacting device for a household appliance with a cover provided with operating and/or display elements, which is inserted into a receptacle in the appliance housing. An electronic control device is attached to the back of the panel, which is electrically connected to the operating and display elements and via cables to functional parts of the device. In this case, mutually matching electrical plug connectors are arranged on the panel and the receptacle, which engage with one another when the panel is inserted or plugged in and electrically connect the control device to the functional parts.

A detailed description of an electric drive can be found in an article in the ATZ magazine, volume 113, 05/2011, pages 360-365 by Erik Schneider, Frank Fickl, Bernd Cebulski and Jens Liebold with the title: Highly integrative and flexible electric drive unit for electric Vehicles, which is probably the closest state of the art. This article describes a drive unit for an axle of a vehicle, which includes an electric motor that is arranged concentrically and coaxially with a bevel gear differential, with a shiftable 2-speed planetary gear set being arranged in the power train between the electric motor and the bevel gear differential, which is also is positioned coaxially to the electric motor or the bevel gear differential or spur gear differential. The drive unit is very compact and allows a good compromise between climbing ability, acceleration and energy consumption due to the switchable 2-speed planetary gear set. Such drive units are also referred to as e-axles or electrically operable drive train.

Such electrically operable drive trains generally require hydraulic devices for cooling and/or for shifting operations in a shiftable transmission.

There is a continuing need to design such hydraulic devices to be particularly easy to assemble, compact and reliable.

The object of the invention is therefore to provide a hydraulic device for an electric drive train with an electric machine that meets these needs. It is also the object of the invention to provide an electrically operable drive train with an improved hydraulic device.

This object is achieved by a hydraulic device for an electric drive train with an electric machine, the hydraulic device comprising a hydraulic reservoir in which an electrically operable hydraulic pump and at least one electrically switchable hydraulic valve are arranged, the hydraulic device having an electrical contacting device which connects the hydraulic reservoir and has first electrical contacting means for electrically connecting the hydraulic pump to the electrical contacting device and second electrical contacting means for electrically connecting the hydraulic valve to the electrical contacting device, and the electrical contacting device also includes a third electrical contacting means, which is arranged outside or inside the hydraulic reservoir and the third electrical contact means elec is trically connected to the first electrical contact means and the second electrical contact means.

The hydraulic device is particularly easy to assemble, since the individual electrical connections are already predefined in a component by the electrical contacting device and do not have to be laid and assembled individually. Furthermore, the hydraulic device can be electrically connected in a simple and assembly-friendly manner by the third electrical contacting means, which is arranged outside of the hydraulic reservoir. Finally, the entire hydraulic device can be prefabricated as a modular component and arranged on an E-axis, for example.

The electrical contacting means are preferably designed as form-fitting and/or non-positive plug-in contacts. In principle, it is also conceivable that the contacting means for a loss th or welding are formed. Furthermore, it is preferred that an electrical contact means is not surrounded by an insulating material.

The electrical contacting device is very particularly preferably configured in such a way that it can be electrically and structurally connected from a mounting direction to at least one hydraulic valve, preferably all hydraulic valves and the hydraulic pump, by plugging it on. In this way, an embodiment of an electrical contacting device can be provided which can be plugged onto the components to be electrically and mechanically connected in one direction and which at the same time implements the mechanical fixing, the electrical contacting and particularly preferably also the sealing against the hydraulic fluid in the hydraulic reservoir.

The electrical contacting device can in particular also be designed in several parts. For example, it would be conceivable to adapt the electrical contacting device to different installation situations by providing adapter elements which, for example, allow the electrical contacting device to be lengthened and/or adapted to different plug/socket systems. In principle, it would be possible to design the electrical contacting device in such a way that an adapter element is electrically and mechanically connected to the third electrical contacting means inside or outside the hydraulic reservoir. In particular, the adapter element can also establish an electrical and mechanical connection to the controller of the electric drive train.

The hydraulic device has a hydraulic reservoir for receiving and storing hydraulic fluid. The hydraulic reservoir preferably has a closable opening for filling in hydraulic fluid. The hydraulic reservoir is preferably designed as an oil pan. The hydraulic reservoir is particularly preferably formed from a plastic.

According to an advantageous embodiment of the invention, it can be provided that the electrical contacting device is designed as a lead frame. Within the meaning of this invention, a lead frame, also occasionally referred to as a connection frame, is a metallic conductor carrier in the form of a plurality of electrical lines arranged in a stationary manner in relation to one another. In particular, the electrical conductors of a lead frame can also be insulated, for example by means of an insulating varnish or a plastic. Furthermore, it is possible for a lead frame to be arranged within a housing and thus to be surrounded at least in sections by a housing material.

It is very particularly preferred that the electrical conductors of a lead frame are surrounded by a plastic which has been guided around the electrical conductors by means of an injection molding process. In this case, the electrical conductors can be designed in particular as inserts in an injection molding tool, which are then subsequently encapsulated in plastic and thus assume a predefined location and position in relation to one another. A lead frame can thus be designed in particular as a component overmoulded with plastic with electrical conductors running inside the component, with the component having a defined, fixed three-dimensional shape.

According to a further preferred development of the invention, it can also be provided that the electrical contacting device has fourth electrical contacting means for making electrical contact with at least one pressure sensor, which are electrically conductively connected to the third electrical contacting means, which also means that a simple electrical connection of a pressure sensor can be achieved through the contacting device can be provided.

Furthermore, it can be provided according to a likewise advantageous embodiment of the invention that the electrically conductive connection between the first electrical contacting means and the third electrical contacting means
and or
the electrically conductive connection between the second electrical contact means and the third electrical contact means
and or
the electrically conductive connection between the fourth electrical contact means and the third electrical contact means is formed by busbars.

The advantageous effect of this configuration is based on the fact that the busbars provide a comparatively high level of mechanical dimensional stability. This is particularly advantageous when the busbars are encapsulated in plastic, so that in addition to the electrical conduction, they also have the function of reinforcement for the structural reinforcement of the plastic encapsulation. It is particularly preferred that the busbars have a cross section that deviates from the circular shape, particularly preferably a rectangular shape.

According to a further particularly preferred embodiment of the invention, it can be provided that the busbars are at least partially, preferably completely, encapsulated by a plastic. An electrical contacting means is advantageously formed at the distal ends of a busbar and is preferably formed monolithically with the busbar.

Alternatively or additionally, it is also possible for the busbars to be surrounded by a plastic. For example, it is conceivable for the busbars to be inserted into an insert body formed from plastic, with the insert body being formed first and the busbars then being connected to the insert body. A busbar can be fixed in a corresponding insert body, for example, by gluing, casting, screwing, hot stamping/hot riveting, pressing, clipping or the like.

Furthermore, the invention can also be further developed in such a way that the electrical contacting device has a drying space positioned within the hydraulic reservoir for accommodating a rotor position sensor. This also simplifies the electrical assembly of the hydraulic device.

In a likewise preferred embodiment variant of the invention, it can also be provided that the electrical contacting device has a first level and a second level running parallel to the first level, the first level and the second level being connected to one another via a connecting section and the busbars within the first Level, the second level and / or the connecting portion extend, whereby a space-optimized design for electrical contacting of the hydraulic pump can be realized, in which the hydraulic pump is arranged, for example, between the first and the second level.

The object of the invention is also achieved by an electrically operable drive train of a motor vehicle comprising an electric machine and a transmission arrangement, the electric machine and the transmission arrangement forming a structural unit and the electrically operable drive train comprising a hydraulic device according to one of claims 1-7.

According to an embodiment of the subject matter of the invention that is preferable in this context, it can be provided that the electrically operable drive train has a control device for controlling the hydraulic pump and the hydraulic valve, the control device being electrically conductively connected to the hydraulic device via the third electrical contacting means of the electrical contacting device, so that a particularly simple and assembly-friendly design of a hydraulic system can be provided. Finally, the invention can also be advantageously implemented in such a way that the electrically operable drive train and the hydraulic device form a structural unit and the electrically operable drive train can thus be prefabricated and installed in the drive train of a motor vehicle.

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

• 1 eine Hydraulikvorrichtung in einer schematischen Querschnittsansicht, und
• 2 eine elektrische Kontaktierungsvorrichtung in einer schematischen perspektivischen Ansicht,
• 3 eine Hydraulikvorrichtung mit Adapterelementen in zwei verschiedenen Ausführungen in schematischen Querschnittsansichten,
• 4 eine Hydraulikvorrichtung mit Adapterelementen in zwei verschiedenen Ausführungen in schematischen Querschnittsansichten, und
• 5 ein Kraftfahrzeug mit einem elektrisch betreibbaren Antriebsstrang in einer schematischen Blockschaltdarstellung.

Show it:

• 1 a hydraulic device in a schematic cross-sectional view, and
• 2 an electrical contacting device in a schematic perspective view,
• 3 a hydraulic device with adapter elements in two different versions in schematic cross-sectional views,
• 4 a hydraulic device with adapter elements in two different designs in schematic cross-sectional views, and
• 5 a motor vehicle with an electrically operable drive train in a schematic block diagram.

the 1 shows a hydraulic device 1 for an electric drive train 2 with an electric machine 3, as exemplified in FIG 5 is reproduced. The hydraulic device 1 shown includes a hydraulic reservoir 4, which is designed as an oil pan and which stores a hydraulic oil, not shown. An electrically operable hydraulic pump 5 and three electrically switchable hydraulic valves 6 are arranged in the hydraulic reservoir 4 .

The hydraulic device 1 also has an electrical contacting device 7 which sealingly extends through the hydraulic reservoir 4 at its head end. Alternatively or additionally, however, it would also be conceivable for a seal to break through the hydraulic reservoir 4 coming from the outside and for the seal to be placed on the outside of the hydraulic reservoir 4 . The seal can be formed in one piece with the contacting device 7 or can be formed as a separate component. The sealing of the hydraulic reservoir 4 can consequently lie between the inside electrical contacting device 7 and the inner wall of the hydraulic reservoir 4 and/or the outer wall of the hydraulic reservoir 4 take place.

First electrical contacting means 8 for electrically connecting hydraulic pump 5 to electrical contacting device 7 (in 1 not visible, but in synopsis with 2 visible) and second electrical contacting means 9 for electrically connecting the hydraulic valve 6 to the electrical contacting device 7 embodied. Both the first electrical contact means 8 and the second electrical contact means 9 are positioned inside the hydraulic reservoir 4 and can—depending on the level of the hydraulic reservoir 4—below the level of the hydraulic oil.

The electrical contacting device 7 has a first level 15 and a second level 16 running parallel to the first level 15, the first level 15 and the second level 16 being connected to one another via a connecting section 17 and the busbars within the first level 15, the second Level 16 and the connecting portion 17 extend. The hydraulic pump 5 is arranged between the first level 15 and the second level 16 . The electrical contacting device 7 is configured in such a way that it can be connected to the hydraulic valves 6 and the hydraulic pump 5 from one mounting direction—from above in the example shown. For this purpose, the first and second electrical contact means 8, 9 have an extension oriented in the assembly direction. The electrical contacting of the third electrical contacting means 10 also takes place in the same direction of installation.

The electrical contacting device 7 also includes a third electrical contacting means 10 which is arranged outside of the hydraulic reservoir 4 . The third electrical contact means 10 is electrically connected to the first electrical contact means 8 and the second electrical contact means 9 . This enables electrical contact to be made from the dry space to the wet space within the hydraulic reservoir 4 . The third electrical contact means 10 is designed as a multi-pole socket, so that complete electrical contact can be established by means of a corresponding plug. Of course, plug/socket variants other than those shown in the exemplary embodiment are conceivable.

From the 2 it can now be seen that the electrical contacting device 7 is designed as a lead frame. In the exemplary embodiment shown, the contacting device 7 is designed as a plastic body in which the busbars for the electrical connection of the third electrical contacting means 10 to the first and second electrical contacting means 8, 9 are embedded.

Of the 2 It is also easy to see that the electrical contacting device 7 has fourth electrical contacting means 12 for making electrical contact with at least one pressure sensor, which are electrically conductively connected to the third electrical contacting means 10 .

Although it's from the 2 not directly due to the plastic encapsulation, is the electrically conductive connection between the first electrical contact means 8 and the third electrical contact means 10 and the electrically conductive connection between the second electrical contact means 9 and the third electrical contact means 10
and the electrically conductive connection between the fourth electrical contact means 12 and the third electrical contact means 10 is formed by busbars. In the exemplary embodiment shown, the conductor rails are completely encapsulated in plastic.

In the 2 It is further shown that the electrical contacting device 7 has a drying space 11 positioned within the hydraulic reservoir 4 for receiving a rotor position sensor. The drying chamber 11 is arranged on the contacting device 7 in such a way that, in the installed state, it is arranged in the immediate vicinity of the rotor of the hydraulic pump 5 or its motor. The drying space 11 is formed in one piece with the electrical contacting device 7 .

3 shows a hydraulic device 1 with adapter elements 22 in two different versions. The top view shows a hydraulic device 1 in which the third electrical contact means 10 of the electrical contact device 7 is arranged outside of the hydraulic reservoir 4 . In this respect, this corresponds in principle to that from the 2 known version.

It can be seen that the electrical contacting device 7 can be sealed off by an inner seal 19 and an outer seal 18 in the region of its connecting section 17 which extends through the hydraulic reservoir 4 . One of the seals 18,19 or all seals 18,19 kings NEN also be formed with the electrical contacting device 7 or the hydraulic reservoir 4 and / or be configured as separate sealing rings.

For the electrical and mechanical connection of the hydraulic device 1 to the drive train 2 or a control device 20 of the drive train 2, the adapter element 22 is connected to the third contacting means 10, as a result of which an electrical connection can be established between the control device 20, the hydraulic pump 5 and the hydraulic valves 6. This electrical connection is in the 3-4 indicated by the dashed line. The assembly can be done, for example, in such a way that first the electrical contact means 7 inside the storage tank 4 is connected to the hydraulic pump 5 and the hydraulic valves 6 and then the hydraulic storage tank 4 is closed. The module formed in this way can then be electrically and mechanically coupled to the adapter element 22 .

The lower figure of the 3 shows an embodiment of the hydraulic device 1, in which the third electrical contact means 10 is arranged within the hydraulic reservoir 4. For electrical contacting, the adapter element 22 is pushed into the hydraulic reservoir 4 , the reservoir 4 then being sealed off from the environment by the seals 18 , 19 on the adapter element 22 .

The installation can then take place, for example, in such a way that the adapter element 22 is first pushed into the hydraulic reservoir 4 and then the electrical contacting means 7 is connected to the adapter element 22 through the bottom opening of the reservoir 4 . After assembly, the hydraulic reservoir 4 can then be closed by the bottom cover 21 .

The embodiments of 3 has in common that the adapter element 22 is already firmly connected to a component of the drive train 2, such as the controller 20, or is designed in one piece with it.

In principle, however, it would also be conceivable for the adapter element 22 to be designed as a completely separate component, as is the case in the embodiments of FIGS 4 is shown.

5 finally shows an electrically operable drive train 2 of a motor vehicle 13 comprising an electric machine 3 and a transmission arrangement 14, wherein the electric machine 3 and the transmission arrangement 14 form a structural unit and the electrically operable drive train 2 comprises a hydraulic device 1 according to one of the preceding claims. The electrically operable drive train 2 also has a control device (not shown) for controlling the hydraulic pump 5 and the hydraulic valve 6, the control device being electrically conductively connected to the hydraulic device 1 via the third electrical contacting means 10 of the electrical contacting device 7 and thus to the hydraulic pump 5 and the hydraulic valve 6 electrically switches or controls. Finally shows the 3 also that the electrically operable drive train 2 and the hydraulic device 1 form a structural unit. The hydraulic reservoir 4 can be arranged in such a way that it is positioned above or below the electric machine 3 and/or the transmission arrangement 14 in the vertical direction.

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

hydraulic device

2

powertrain

3

electric machine

4

reservoir

5

hydraulic pump

6

hydraulic valve

7

contacting device

8th

contacting means

9

contacting means

10

contacting means

11

drying room

12

contacting means

13

motor vehicle

14

gear arrangement

15

level

16

level

17

connection section

18

outer seal

19

inner seal

20

control device

21

bottom cover

22

adapter element

Claims (10)

Hydraulic device (1) for an electric drive train (2) with an electric machine (3), the hydraulic device (1) comprising a hydraulic reservoir (4) in which an electrically operable hydraulic pump (5) and at least one electrically switchable hydraulic valve (6 ) are arranged, characterized in that the hydraulic device (1) has an electrical contacting device (7) which extends through the hydraulic reservoir (4) and first electrical contacting means (8) for electrically connecting the hydraulic pump (5) to the electrical contacting device (7 ) and second electrical contacting means (9) for electrically connecting the hydraulic valve (6) to the electrical contacting device (7), and the electrical contacting device (7) further comprises a third electrical contacting means (10) which is outside or inside the hydraulic reservoir ( 4) nec is arranged and the third electrical contact means (10) is electrically connected to the first electrical contact means (8) and the second electrical contact means (9). Hydraulic device (1), after claim 1 , characterized in that the electrical contacting device (7) is designed as a lead frame Hydraulic device (1), after claim 1 or 2 , characterized in that the electrical contacting device (7) has fourth electrical contacting means (12) for electrical contacting at least one pressure sensor, which are electrically conductively connected to the third electrical contacting means (10). Hydraulic device (1) according to one of the preceding claims, characterized in that the electrically conductive connection between the first electrical contact means (8) and the third electrical contact means (10) and/or the electrically conductive connection between the second electrical contact means (9) and the third electrical contacting means (10) and/or the electrically conductive connection between the fourth electrical contacting means (12) and the third electrical contacting means (10) is formed by busbars. Hydraulic device (1), after claim 4 , characterized in that the busbars are at least partially, preferably completely surrounded by a plastic, in particular encapsulated. Hydraulic device (1) according to one of the preceding claims, characterized in that the electrical contacting device (7) has a drying space (11) positioned inside the hydraulic storage tank (4) for receiving a rotor position sensor. Hydraulic device (1) according to one of the preceding claims, characterized in that the electrical contacting device (1) has a first plane (15) and a second plane (16) running parallel to the first plane (15), the first plane (15 ) and the second level (16) are connected to one another via a connecting section (17) and the busbars run within the first level (15), the second level (16) and/or the connecting section (17). Electrically operable drive train (2) of a motor vehicle (13) comprising an electric machine (3) and a gear arrangement (14), the electric machine (3) and the gear arrangement (14) forming a structural unit and the electrically operable drive train (2) comprises a hydraulic device (1) according to any one of the preceding claims. Electrically operable drive train (2) according to claim 8 , characterized in that the electrically operable drive train (2) has a control device for controlling the hydraulic pump (5) and the hydraulic valve (6), the control device being electrically conductively connected via the third electrical contacting means (10) of the electrical contacting device (7) to the Hydraulic device (1) is connected. Electrically operable drive train (2) according to claim 8 or 9 , characterized in that the electrically operable drive train (2) and the hydraulic device (1) form a structural unit.

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