System housing for drive systems

Abstract

The invention relates to a housing (1), in particular a housing for an electric drive system of a vehicle, wherein the housing (1) is designed as a system housing and is provided for accommodating a plurality of system components, and wherein the housing (1) has a housing wall (11) produced by a casting tool, and wherein a plurality of interfaces are provided in or on the housing wall (11) for connecting the housing (1) to components located outside or inside the housing (1). The invention also relates to the use of a housing (1) according to any of the preceding claims as a system housing for an electric drive axle of a motor vehicle.

Description

Technical Field

[0001] The invention relates to a housing, in particular a housing for an electric drive system of a vehicle, wherein the housing is designed as a system housing and is provided for accommodating a plurality of system components, and wherein the housing has a housing wall produced by a casting tool and a plurality of interfaces are provided in or on the housing wall for connecting the housing to components located outside or inside the housing. The invention also relates to the use of the housing as a system housing for an electric drive axle of a motor vehicle. Background Art

[0002] In drive technology, different system components, such as actual drives or motors, one or more transmissions and associated control and regulation technologies must be placed in a housing in a protected manner. One possibility of this placement is a modular housing, which is composed of multiple individual components, wherein each individual component accommodates a system component. The disadvantage of this modular housing is that the connection of the individual components is complicated. In addition, the heat transfer between the individual components is hindered by the separation position, which hinders the heat transfer from one system component to another system component or the heat dissipation by the cooling system. Another possibility of placing different system components is a so-called system housing, which surrounds multiple system components. The heat transfer between the various areas of the system housing is significantly better than the heat transfer in the modular housing. However, in the known system housing, there is still always a high cost for installing the system components in the housing and for connecting the system housing with other components arranged outside.

[0003] DE 10 2013 021 745 A1 describes a converter motor having a stator housing. The converter motor has a cooling channel with two connections for a cooling medium. The stator housing also has a plate-shaped section for carrying the converter, wherein the plate-shaped section is preferably embodied as a cast part in one piece with the stator housing.

[0004] DE 10 2013 217890 A1 discloses an electric motor housing having a first housing part for accommodating an electric motor stator and a second housing part for accommodating a power electronic module. The first housing part comprises further sections, for example a section for accommodating a transmission. A cooling channel having two connections is provided for the electric motor, wherein the cooling channel extends in the first housing part. Preferably, the first housing part and the second housing part form an integral housing.

[0005] DE 10 2012 016208 A1 relates to a housing with a cooling jacket for an electric motor. The housing comprises a cooling channel with two connections for conducting a coolant through the housing. The housing also comprises a section for accommodating power electronics and a transmission. Summary of the invention

[0006] A housing, in particular a housing for an electric drive system of a vehicle, is proposed, wherein the housing is implemented as a system housing and is provided for accommodating a plurality of system components. The housing has a housing wall manufactured by a casting tool, wherein a plurality of interfaces are provided in or on the housing wall for connecting the housing to components located outside or inside the housing. The interfaces include at least one coolant inlet and / or coolant outlet, at least one housing fixing point for the housing on other components, in particular for fixing the housing on the vehicle, for fixing the inner housing in the interior of the housing, at least one inner housing joint for fixing the transmission cover, and at least one electronic device cover joint for fixing a cover for power electronic devices. The housing according to the invention is implemented as a system housing and is particularly suitable for accommodating a plurality of system components of an electric drive system (also referred to as an E-axle) for a vehicle. However, the housing according to the invention can also be used in other technical fields in which a plurality of system components are arranged adjacent to each other, for example in the field of machine tools. The housing according to the invention has a housing wall, which is manufactured by a casting method. The housing wall is typically formed of a metal material, for example, an iron-based alloy or an aluminum-based alloy. Manufacturing in a casting method enables the cost-effective manufacturing of complex geometries of housing walls in mass production. After manufacturing in a casting method, the area of ​​the housing wall can be optionally reprocessed using other manufacturing methods, such as by milling, drilling, grinding or similar methods. According to the present invention, a plurality of interfaces are provided in or on the housing wall for connecting the housing to components located outside or inside the housing: at least one coolant inlet and / or coolant outlet is provided so as to enable a simple connection of the cooling system to the system housing. Coolant is required to cool one or more system components to be arranged in the housing. The coolant inlet or coolant outlet is usually formed by an opening in the housing wall, which can be additionally provided with a flange or thread. In addition, the interface, coolant inlet or coolant outlet can have one or more areas for accommodating a seal. In addition, as an interface, at least one housing fixing point for the housing is provided on other components. One or more such housing fixing points are used to fix the housing to a vehicle or other upper-level components. Such housing fixing points can be implemented, for example, by a stop surface combined with a receiving portion for a connecting element, such as a screw. Alternatively, the housing fixing points can also be implemented as plug connections or snap connections. Housing fixing points are usually used to fix, position and fasten the housing to other components. In addition, at least one inner housing connection is provided as an interface for fixing the inner housing in the interior of the housing. The inner housing can be understood here as a component that is arranged at least partially parallel to the housing wall and is fixed in the interior of the housing. After such an inner housing is arranged, a chamber is generated between the housing wall and the inner housing, which chamber can be used as a channel for a coolant. A two-piece housing wall is generated by arranging the inner housing.In this way, coolant channels that would form undercuts that are difficult to manufacture when integrated into a one-piece housing wall can be simply realized by placing an inner shell. Such an inner shell can be made of a metal material, for example, by extrusion. Alternatively, the inner shell can be formed by one or more plates or by one or more plastic parts. The inner shell joint is an interface for fixing the inner shell. The inner shell joint can be implemented as a stop surface, for example, but can also be implemented as a form-fitting interface, for example in the form of a plug-in receiving portion. In addition, the inner shell joint can be implemented as an adhesive surface or a welding surface for placing the inner shell. In addition, the housing according to the present invention has at least one transmission cover joint for fixing the transmission cover as an interface. Usually, the system housing according to the present invention is also particularly configured to accommodate a transmission. In order to cover the transmission, a transmission cover is required, which is connected to the housing via at least one transmission cover joint. The transmission cover joint is implemented, for example, as a flat connection surface, and a receiving area for connecting elements, such as screws, is arranged near the connection surface. The transmission cover joint can also have one or more receiving portions for sealing elements. The transmission cover connector can surround or enclose a larger opening in the housing wall, through which at least a portion of the transmission can be introduced into the system housing. Finally, the housing according to the present invention includes at least one electronics cover connector as an interface for fixing a cover for power electronics. Power electronics are usually placed in the system housing separately from other system components. In order to introduce the power electronics into the housing, an opening is provided, which must be closed by an electronics cover before being put into operation. Such an electronics cover can be implemented as a cover, for example. The electronics cover interface is an interface to which the electronics cover is connected. The electronics cover connector can be implemented similarly to the transmission cover connector.

[0007] In one embodiment, it is provided that the interface also includes at least one foot point for fixing the element on the housing and / or a housing casting for a locking system and / or a decoupling element and / or at least one unit interface and / or at least one plug fixing point for fixing the electrical connector on the housing and at least one screw point for the intermediate shaft. The housing can additionally have one or more of the above-mentioned interfaces. Different interfaces can be freely combined with each other here. This other optional interface is a foot point for fixing the element on the housing. The element to be placed on this foot point can be, for example, a sensor, such as a temperature sensor. The foot point can realize the simple placement of such an element without the need for additional intermediate components. In addition, the housing can have a housing casting for a locking system and / or a decoupling element as an interface. Here, the housing casting is understood as an outwardly oriented area of ​​the housing wall, in which system components can be arranged. Therefore, the housing casting provides an additional internal volume in the housing. For example, a locking system can be arranged in the housing casting. This locking system is a locking device for a transmission, which is activated once a vehicle equipped with a drive system is parked. By means of this locking device, the transmission is locked and the vehicle cannot roll away. Alternatively, a decoupling element can be arranged in the housing casting. This decoupling element can temporarily separate the drive, such as the motor, from the transmission, for example, in order to achieve idling. This decoupling element can also be referred to as a disconnector. In addition, the housing can have at least one unit interface as an interface. On the unit interface, a unit that does not directly belong to the drive system, such as an air conditioning compressor as part of the vehicle's air conditioning system, can be arranged. By providing one or more such unit interfaces, additional connecting elements for connecting these units are saved. In addition or alternatively, the housing can have a plug fixing point as an interface for fixing an electrical connector on the housing. This plug fixing point is used for the fastening arrangement of electrical connection elements, which are required, for example, for wiring different system components in the system housing to each other. Through the plug fixing point, the electrical component can be directly fixed on or in the housing wall in a simple manner and without the need for additional receptacles. As another interface, at least one screw point for an intermediate shaft can be provided. The intermediate shaft is used to export torque from the system housing to a transmission arranged outside, such as a differential of an additional shaft. Such a screw point usually comprises an opening for passing the intermediate shaft and a fixing area, on which a cover or a jacket of the intermediate shaft can be fixed in a sealing manner relative to the system housing. Of course, other interfaces for arranging other components on the housing wall can be provided on the housing.

[0008] In another embodiment, it is provided that the interface is adapted to the requirements of the user of the housing in terms of its type and position on or in the housing. The interface is used to connect the housing to other components. In order to achieve optimal integration of the housing into other components, especially into a vehicle, the interface is adapted to the requirements of the user of the housing, which are derived from other components of the upper-level component. If the user wishes, for example, to arrange the housing in a vehicle with an air conditioning system and a locking device, the corresponding interfaces, in the example, the unit interface for the air conditioning compressor and the housing casting for the locking system are arranged at a position that enables optimal interaction with other components of the vehicle.

[0009] In addition, it is provided that the housing, in particular the housing wall, has at least one operating point, which is arranged as a gripping point when processing the housing and / or when installing system components in the housing, wherein the operating point is arranged at the following position in the housing, which remains unchanged according to the requirements of the user of the housing when the interface is adapted on or in the housing in terms of its type and position. In this embodiment, at least one operating point is arranged on the housing. The operating point is used as a gripping point, at which the housing or the housing wall is gripped during installation. When the housing is automatically installed, the operating point can be gripped and accommodated by a gripping arm of a robot, for example. Such an operating point can have a cylindrical circumferential surface or one or more flat wrench surfaces for transmitting good forces and torques during installation. Optionally, the operating point can have an optically high contrast area, which makes it easy to recognize the operating point by a camera during automatic processing. The operating point can be implemented, for example, as a simple cylindrical bolt, which has a embossing portion on its end face, which contrasts optically with the remaining surface of the bolt. In order to simplify the manufacture and processing of the housing, the position of the operating point is selected so that it remains constant even when the type and position of the interface change. One or more operating points that are always arranged at the same position in space make it possible to use a single casting tool to manufacture different types of housings. On this casting tool, in order to adapt the type and position of the interface, only the corresponding inserts need to be changed, but the area of ​​the tool used to manufacture the operating points can remain unchanged. This significantly reduces tool costs when adapting the housing. In addition, the unchanged positioning of the operating point has the advantage that existing installation devices, such as production lines, do not have to be changed in terms of gripping the housing. Due to the constant arrangement of the operating points, the same gripping tool can be used when performing the same or very similar movements, which significantly reduces the cost for mounting the housing.

[0010] In another embodiment, it is provided that the housing wall is designed in two or more parts. In the simplest embodiment, the housing wall is designed in one part, which means that the housing wall is produced as a single component by means of a casting tool. In the case of more complex structures or larger housings, the housing wall can also be designed in two or more parts. The individual components are then produced separately in one or different casting molds. The components of the housing wall can then be joined side by side to produce a single-layer housing wall. Alternatively, a two-layer or multi-layer housing wall can also be formed from the components, wherein the components of the housing wall extend at least partially parallel to each other.

[0011] In addition, it is provided that the housing has a plurality of housing chambers, which are provided for accommodating different system components, such as motors, transmissions and power electronics. In this embodiment, the interior of the housing is divided into a plurality of housing chambers. These housing chambers are provided for accommodating different system components. The housing chambers are at least partially separated from each other. A transition portion or a channel can be provided between the housing chambers, for example, so that a connection portion, such as a control line, can be guided from one housing chamber to the next housing chamber. However, a single or multiple housing chambers can also be sealed relative to other housing chambers. Such a sealed housing chamber is suitable, for example, for accommodating a transmission lubricated by a liquid lubricant. In this case, the seal prevents the lubricant from penetrating into other housing chambers. When manufacturing the housing, multiple housing chambers can be realized by a single casting tool.

[0012] In one embodiment, it is provided that the housing wall is formed from a heat-conducting material, thereby ensuring an unimpeded heat transfer between the plurality of housing chambers. Metallic materials have particularly good thermal conductivity. In practice, an aluminum substrate has proven to be a suitable material for the housing wall due to its good thermal conductivity and high mechanical strength.

[0013] In another embodiment, it is provided that a first housing chamber for accommodating an electric motor is provided, the first housing chamber having an axial direction parallel to the rotor shaft of the electric motor to be accommodated by the housing chamber, and another housing chamber for accommodating power electronics is provided, wherein the other housing chamber is arranged along the axial direction of the first housing chamber. In this embodiment, a housing chamber for accommodating an electric motor is provided, wherein the housing chamber has a shape adapted to the electric motor. The electric motor has a rotor with a rotor shaft. The direction in which the axis of rotation of the rotor shaft extends when the electric motor is installed, or the direction oriented parallel to the direction is referred to as the axial direction of the housing chamber. Another housing chamber for accommodating power electronics is arranged along the axial direction of the housing chamber for accommodating the electric motor. This arrangement can also be referred to as axial installation of a housing chamber for power electronics on a housing chamber of an electric motor.

[0014] In an alternative embodiment, it is provided that a housing chamber for accommodating a motor is provided, the housing chamber having a circumferential surface, the circumferential surface extending around the rotor shaft of the motor to be accommodated by the housing chamber at intervals, and another housing chamber for accommodating power electronics is provided, wherein the housing chamber is arranged on the circumferential surface of the housing chamber. In an alternative to the above-mentioned embodiment, another housing chamber is provided, which is arranged on the circumferential surface of the first housing chamber, wherein the first housing chamber is provided for accommodating the motor and the other housing chamber is provided for accommodating power electronics. The circumferential surface of the housing chamber for the motor refers to the surface arranged radially around the rotor shaft, around the rotor and around the stator. The circumferential surface is a surface different from the end surface arranged axially. The arrangement of the housing chamber on the circumferential surface of the housing chamber provided for the motor can also be referred to as circumferential surface installation. The arrangement of different chambers relative to each other in the housing can be individually coordinated according to the specific application of the housing. Of course, in addition to the two housing chambers described above, other housing chambers for other system components can also be provided.

[0015] Furthermore, the use of a housing according to one of the above-described embodiments as a system housing for an electric drive axle of a motor vehicle is proposed. The housing is particularly suitable for accommodating system components belonging to the electric drive axle of a motor vehicle. Such system components are, for example, a drive formed by an electric motor, at least one transmission and at least one power electronic device. The use of the housing in electric drive technology is particularly advantageous, because in electric drive technology, reliable solutions are required with a simple system structure. Furthermore, the waste heat generated in electric drive technology must be reliably conducted away from some system components, for which the described housing is particularly suitable due to its very good thermal conductivity.

[0016] In one embodiment of the application, it is provided that the electric drive shaft is part of the drive of a hybrid vehicle or a purely electric vehicle. The use of the housing according to one of the aforementioned embodiments is particularly advantageous when the electric drive shaft is arranged in a hybrid vehicle. A hybrid vehicle has a plurality of drive components which must be combined and synchronized with one another, for which a plurality of interfaces between the components are required. The housing according to one of the aforementioned embodiments can be optimally adapted to the requirements in a hybrid vehicle due to its plurality of different interfaces. Of course, the housing can also be used in vehicles which are only electrically driven.

[0017] In the housing according to the invention, many functions are bundled in a single system housing. In the best case, all necessary interfaces for mounting the system components located in the housing and for mounting the housing on the vehicle or other higher-level components are provided on the housing wall. The transmission according to the invention can then be installed with very little effort and without complex connecting elements. By changing the type and position of the interfaces, the housing can be adapted to different applications. For production, a casting tool is provided, which has flexible inserts for designing different interfaces. In order to adapt the housing to different requirements, it is then only necessary to replace these flexible inserts, which significantly reduces the tool costs when manufacturing housings of different embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Exemplary embodiments of the invention are explained in more detail with reference to the drawings and the following description.

[0019] Figure 1 A schematic perspective view of a housing according to an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0020] In the following description of embodiments of the invention, identical or similar elements are denoted by the same reference numerals, wherein a repeated description of these elements is omitted in individual cases. The figures merely schematically illustrate the subject matter of the invention.

[0021] Figure 1 A schematic perspective view of a housing 1 according to an embodiment of the present invention is shown. The housing 1 is shown schematically without system components installed therein or thereon. The housing 1 is based on a one-piece housing wall 11, which is manufactured by a casting method. The housing wall 11 is reworked, for example, in the area of ​​some interfaces by milling, drilling and grinding. The shown housing 1 comprises three housing chambers A, B, C. The housing chamber A, which is provided for accommodating the electric motor, faces to the right front. The axial direction A1 of the housing chamber A is symbolically indicated by a dotted line. A further housing chamber B is arranged behind the housing chamber A in the axial direction A1, which further housing chamber is in Figure 1In the view shown, it is covered by other parts of the housing 1. The housing chamber B is configured to accommodate power electronics. Therefore, in the embodiment shown, the axial installation of the power electronics relative to the motor is realized. In this view, another housing chamber C is arranged on the side facing the left, and the other housing chamber is also covered by the housing wall 11. The housing chamber C is configured to accommodate a transmission. The housing chambers A, B, and C are at least partially separated from each other by a partition wall. The housing 1 or the housing wall 11 has different interfaces for connecting to components located outside or inside the housing 1. Three housing fixing points GP are drawn as an example, and the housing fixing points are arranged to connect the housing 1 to a superior component, such as a vehicle. The drawn housing fixing points GP are arranged on the right edge and the upper edge of the housing wall 11 and on the side facing the left front in the figure. All housing fixing points GP include flat stop surfaces and accommodating openings for fixing elements, such as screws. Of course, other housing fixing points GP can be set on the housing 1. In the upper region, approximately in the middle of the illustration, the coolant inlet K1 and the coolant outlet KA arranged side by side can be seen. These two interfaces are provided for introducing and discharging the coolant for cooling the system components located in the housing 1. The coolant inlet K1 and the coolant outlet KA each have a receptacle for a sealing element, which is implemented as an inner chamfer. On the upper edge adjacent to the coolant outlet KA, a foot point FP for fixing the element on the housing 1 is arranged. The foot point FP is an interface produced by milling in the housing wall 11. At the foot point FP, for example, a sensor can be arranged and fixed, which determines the temperature of the housing 1. Other foot points FP can be provided at other parts of the housing 1 for accommodating other elements. A plurality of inner shell joints IM are arranged inside the housing chamber A. The inner shell joint IM is configured as a rib protruding into the interior space, which has a flat bearing surface directed radially inward. The inner shell joint IM is provided for accommodating the inner shell in the interior of the housing chamber A. Such an inner shell can be implemented, for example, as a hollow cylinder, whose outer surface is connected to the inner shell joint IM by an adhesive connection. After such an inner shell is installed, a cavity is generated between the inner shell and the inner wall of the housing chamber A, which cavity can be used for the flow of coolant. As a result, a cooling jacket can be provided in a simple manner in the wall of the housing chamber A provided to accommodate the motor. A transmission cover joint GA is arranged around the housing chamber C, facing the left rear and covered by the housing wall 11. The transmission cover joint GA is an interface for connecting the housing 1 to a transmission cover, such as a transmission cover. In the embodiment shown, the transmission cover joint GA is implemented as a flat surface, which surrounds the housing chamber C. Here, the transmission cover joint GA has threaded holes at regular intervals, into which screws can be introduced to fix the transmission cover. In addition, a screw point AW for the intermediate shaft is arranged on the side of the housing 1 facing the left front.This interface allows the intermediate shaft to pass outward from the transmission arranged in the housing chamber C. The screw point AW comprises a cylindrical through-hole passing through the housing wall 11 and a fastening flange surrounding the cylindrical through-hole.

[0022] In the embodiment shown, the housing 1 also includes a plurality of operating points HP, which are implemented here as pins and which protrude from the housing wall 11. All the operating points HP shown point to the right front in the figure. Blind holes are arranged on the end faces of the operating points HP, which form an optical contrast with the end faces. The operating points HP are provided as gripping areas, on which the housing 1 can be gripped and fixed when installing system components or on a vehicle. The shape of the operating points HP allows simple gripping by an automated mounting device with a correspondingly shaped gripper. By optical contrast of the blind holes with the rest of the end faces of the operating points HP, these operating points can also be automatically and well identified by a camera, which is advantageous in the fully automated mounting of the housing 1.

[0023] The invention is not limited to the embodiments described here and the aspects emphasized therein. Rather, within the scope given by the claims, numerous variations are possible within the purview of a person skilled in the art.

Claims

1. A housing (1), wherein: The housing (1) is implemented as a system housing and is provided for accommodating a plurality of system components, wherein the housing (1) has a housing wall (11) manufactured by a casting tool, and wherein a plurality of interfaces are provided in or on the housing wall (11) for connecting the housing (1) to components located outside or inside the housing (1), characterized in that the interfaces have at least one coolant inlet and / or coolant outlet (K1, KA), at least one housing fixing point (GP) for the housing (1) on another component, at least one inner housing joint (IM) for fixing the inner housing inside the housing (1), at least one transmission cover joint (GA) for fixing a transmission cover, and at least one electronics cover joint for fixing a cover for power electronics, wherein the inner housing is implemented as a hollow cylinder, the outer surface of the inner housing being connected to the inner housing joint IM by an adhesive connection, whereby a cavity is generated between the inner housing and the inner wall of a housing chamber (A) for accommodating the motor, the cavity being usable for the flow of coolant.

2. The housing (1) according to claim 1, characterized in that The interface also includes at least one foot point (FP) for fixing the element on the housing (1) and / or a housing casting for a locking system and / or for a decoupling element and / or at least one unit interface and / or at least one plug fixing point for fixing the electrical connector on the housing (1) and at least one screw point (AW) for an intermediate shaft.

3. The housing (1) according to claim 1, characterized in that The interface is adapted in terms of its type and position on or in the housing (1) to the requirements of a user of the housing (1).

4. The housing (1) according to claim 1, characterized in that The housing (1) has at least one operating point (HP) which is provided as a gripping point when machining the housing (1) and / or when installing a system component in the housing (1), wherein the operating point (HP) is arranged at a position in the housing (1) which remains unchanged when the interface is adapted on or in the housing in terms of its type and position according to the requirements of a user of the housing (1).

5. The housing (1) according to claim 1, characterized in that The housing wall (11) is embodied in two or more parts.

6. The housing (1) according to claim 1, characterized in that The housing (1) has a plurality of housing chambers (A, B, C) which are provided for accommodating various system components.

7. The housing (1) according to claim 6, characterized in that The housing wall (11) is formed from a heat-conducting material, thereby ensuring an unimpeded heat transfer between the plurality of housing chambers (A, B, C).

8. The housing (1) according to claim 6, characterized in that A housing chamber (A) is provided for accommodating an electric motor, the housing chamber having an axial direction (A1) which is parallel to the rotor shaft of the electric motor to be accommodated by the housing chamber (A), and another housing chamber (B) is provided for accommodating power electronic devices, wherein the housing chamber (B) is arranged along the axial direction (A1) of the housing chamber (A).

9. The housing (1) according to claim 6, characterized in that A housing chamber (A) is provided for accommodating an electric motor, the housing chamber having a circumferential surface which extends at intervals around a rotor shaft of the electric motor to be accommodated by the housing chamber (A), and another housing chamber (B) is provided for accommodating power electronic devices, wherein the housing chamber (B) is arranged on the circumferential surface of the housing chamber (A).

10. The housing (1) according to claim 1, characterized in that The housing (1) is a housing for an electric drive system of a vehicle.

11. The housing (1) according to claim 1, characterized in that The housing fixing point (GP) is used to fix the housing (1) on the vehicle.

12. The housing (1) according to claim 4, characterized in that The housing wall (11) has at least one operating point (HP).

13. The housing (1) according to claim 1, characterized in that The housing (1) has a plurality of housing chambers (A, B, C) which are provided for accommodating an electric motor, a transmission and power electronics.

14. Use of a housing (1) according to any one of the preceding claims as a system housing for an electric drive axle of a motor vehicle.

15. The use according to claim 14, characterized in that: The electric drive axle is part of the drive of a hybrid vehicle or a purely electric vehicle.

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