Floor assembly and vehicle charging system

Abstract

The invention relates to a floor assembly (2) for an inductive vehicle charging system (1), having: a housing (7); a floor plate (8); and at least one cooling circuit (11) formed in the housing interior (12) for cooling magnetic field conductors (10) and an energy coil (9). Efficient cooling is achieved in that the respective cooling circuit (11) has at least one heat transfer chamber (21) which is formed in an edge region (22) of the housing interior (12) and is delimited by the floor plate (8).

Description

[0001] Floor assembly and vehicle loading system

[0002] The invention relates to a floor assembly for an inductive vehicle charging system according to the preamble of claim 1. The invention also relates to an inductive vehicle charging system equipped therewith, which is configured to charge a vehicle battery with electrical energy for inductive energy transfer between the floor assembly and a vehicle assembly.

[0003] Inductive vehicle charging systems for charging a battery of battery-electric vehicles have a stationary induction charging device, which can also be referred to as a ground assembly (GA), and a mobile induction charging device, which can also be referred to as a vehicle assembly (VA). The ground assembly is arranged or mounted on a surface, which can be formed, for example, by the floor of a garage or parking lot. The vehicle assembly, on the other hand, is arranged on the respective motor vehicle, preferably on an underbody of the motor vehicle. The ground assembly and the vehicle assembly are configured or set up for electromagnetic interaction so that electrical energy can be transferred from the vehicle charging system to the battery-electric vehicle and vice versa.

[0004] In the present context, a "configuration" is synonymous with a "design" and / or "arrangement", so that the phrase "configured so that" is synonymous with the phrase "designed and / or arranged so that".

[0005] During operation of the vehicle charging system, heat loss occurs, among other things, in the floor assembly. This heat is primarily introduced into a base plate of the floor assembly and can be dissipated from there by thermal radiation or convection to the ambient air, on the one hand, and by heat conduction to the subsurface, on the other. However, at relatively high transmission power levels of the floor assembly and / or at high ambient temperatures, heat dissipation is insufficient; in particular, undesirable heat hotspots can arise on critical components of the floor assembly.

[0006] A generic floor assembly is, for example, from the

[0007] DE 102020 215 074 A1. It comprises a housing having a housing interior, as well as a base plate for stationary arrangement on a base, which delimits the housing interior at the bottom and which protrudes laterally beyond the housing with a collar. At least one energy coil for generating an alternating electromagnetic field for inductive energy transmission is arranged in the housing interior. In addition, several magnetic field conductors are arranged in the housing interior, which are arranged between the base plate and the energy coil. Furthermore, a closed cooling circuit for cooling at least the magnetic field conductors and the energy coil is formed in the housing interior, in which cooling air circulates during operation of the cooling circuit and which has at least one fan for driving the cooling air.In the known base assembly, a lower cavity is formed in the housing interior, which extends between the magnetic field conductors and the base plate across the entire housing, and an upper cavity is formed in the housing interior, which extends between the power coil and a housing cover across the entire housing. Between a lateral housing wall on the one hand and the magnetic field conductors and the power coil on the other hand, connecting openings are formed in the housing interior, via which the lower cavity is fluidly connected to the upper cavity. During operation of the cooling circuit, the cooling air flows from such a connecting opening, which is located on a first side of the housing, through the lower cavity to the opposite second side of the housing.From there, the cooling air flows through the connecting opening arranged on this second side of the housing into the upper cavity and from there flows back to the opposite first side of the housing.

[0008] Another floor assembly with such a closed cooling circuit is known, for example, from DE 102020212 388 A1.

[0009] From DE 10 2022 203 488 A1, a base assembly with an open cooling circuit is known in which the cooling air is sucked in from the environment and released back into the environment after flowing through the interior of the housing.

[0010] A particular problem with cooling such a floor assembly is the different requirements placed on it, which can interfere with or counteract one another. During operation of the floor assembly, the waste heat is generated primarily within the respective energy coil, in the magnetic field conductors, and in the floor plate. To ensure that any road-legal passenger vehicle can drive over it, the space available for the floor assembly within the housing is limited to a flat volume that is built on the ground, embedded in, or integrated into the ground, and is often designed in a cuboid shape. It must be ensured that the floor assembly can be driven over without damage. A further challenge arises from inductive energy transmission or inductive power transmission, i.e. the transmission of electrical power using high-frequency magnetic fields.This inductive energy or power transmission is only particularly effective if there are no electrical conductors between the transmitting unit and the receiving unit. This eliminates the use of electrically conductive materials, especially metals, in this area. In the vehicle charging system, the transmitting unit is located in the floor assembly when charging the vehicle battery, while the receiving unit is located in the vehicle assembly. Added to this is the high cost pressure that prevails in the automotive industry due to the high volumes of all products.

[0011] The present invention addresses the problem of providing an improved embodiment for a floor assembly of the type described above or for a vehicle charging system equipped therewith, which is characterized in particular by a cost-effective, compact cooling of the floor assembly.

[0012] This problem is solved according to the invention by the subject matter of the independent claim. Advantageous embodiments are the subject matter of the dependent claims.

[0013] The invention is based on the general idea of ​​designing the respective cooling circuit in the housing such that the cooling air is circulated between an edge region of the housing interior and a central region of the housing interior during operation of the cooling circuit. For this purpose, the cooling air is supplied from the edge region below the magnetic field conductors to the central region and is discharged from the central region above the power coil and returned to the edge region. The invention utilizes the finding that, during operation of the base assembly, heat from the edge region can be dissipated relatively easily via the adjacent flange of the base plate, while heat accumulates in the central region, which is comparatively far away from the flange.Although heat transfer to the base plate also takes place in the central area, heat conduction within the base plate is associated with conduction losses that depend on the conduction path, making heat conduction less effective over longer distances. The inventive design of each cooling circuit circulates the cooling air between the central area and the edge area during operation, so that cooler cooling air is directed from the edge area to the central area, absorbs heat there, and is then returned to the edge area, which is better cooled via the collar. This allows the temperature level within the housing interior to be homogenized, which improves heat dissipation and cooling of the base assembly. Since a closed cooling circuit is used here, the costs of implementing this type of cooling are comparatively low.In order to be able to realize the proposed circulation of the cooling air in the form of a compact design within the housing, cooling channels are used in the base assembly according to the invention, which are also characterized by a targeted guidance of the cooling air.

[0014] In detail, the invention proposes that the respective cooling circuit has at least one heat transfer chamber through which the cooling air flows during operation of the cooling circuit, which heat transfer chamber is formed in an edge region of the housing interior and is delimited by the base plate. This significantly improves the heat transfer between the cooling air and the base plate in the edge region. Within this heat transfer chamber, the edge region can be equipped in particular with heat-conducting elements, which can be formed, for example, by ribs and / or fins and / or baffles. Such heat-conducting elements are expediently connected to the metallic base plate in a heat-conducting manner. Aluminum is a particularly suitable metal. A soldering or welding process is a particularly suitable joining technology.According to the invention, the respective cooling circuit has at least one lower cooling channel which, during operation of the cooling circuit, guides the cooling air below the magnetic field conductors from the respective heat transfer chamber to a central region of the housing interior. This central region is enclosed by the peripheral edge region. Furthermore, the respective cooling circuit has at least one upper cooling channel which, during operation of the cooling circuit, guides the cooling air above the power coil from the central region of the housing interior to the peripheral region of the housing interior. The respective cooling circuit is equipped with at least one central cooling channel which, during operation of the cooling circuit, guides the cooling air in the central region of the housing interior from the respective lower cooling channel to the respective upper cooling channel.In addition, each cooling circuit has at least one peripheral cooling channel, which, during operation of the cooling circuit, guides the cooling air in the peripheral region of the housing interior from the respective upper cooling channel to the respective heat transfer chamber. During operation of the cooling circuit, the cooling air is circulated accordingly by being guided from the heat transfer chamber through the respective lower cooling channel to the central cooling channel, from there flowing to the respective upper cooling channel, being guided therein to the respective peripheral cooling channel, and from there flowing back to the respective heat transfer chamber.

[0015] According to an advantageous embodiment, at least one of the magnetic field conductors can form a central magnetic field conductor, which is arranged in the central region of the housing interior and is supported in a heat-conducting manner on the base plate via a support foot. The respective support foot can be made of a heat-conducting material, preferably a metal, and can be connected in a heat-conducting manner to the magnetic field conductor and to the base plate. For example, the support foot can be welded, soldered, or glued to the respective magnetic field conductor and / or to the base plate. Furthermore, the respective support foot can be integrated into the respective lower cooling channel in such a way that, during operation of the cooling circuit, the cooling air flows towards, around, and / or through the respective support foot for heat transfer. This allows heat to be transferred from the support foot to the cooling air.

[0016] The support foot can be arranged in the respective lower cooling channel such that cooling air flows around its outer side. Optionally, the support foot can have at least one heat-conducting element, such as a cooling fin, on its outer side to improve heat transfer to the cooling air. Likewise, the support foot can have at least one channel through which cooling air can flow and be integrated into the respective lower cooling channel such that the cooling air flows through the channel of the support foot, i.e., through the support foot. The support foot can have heat-conducting elements, such as fins and / or slats, in its channel.

[0017] According to an advantageous development, it can be provided that the respective support foot is supported on the respective central magnetic field conductor in a support region in a heat-transferring manner, wherein the respective upper cooling channel is guided laterally around a projection of the support region running parallel to the housing height direction. In other words, the projection of the support region running parallel to the housing height direction is recessed from the course of the respective upper cooling channel. This creates a continuous support path in the housing height direction, which extends from the base plate through the support foot and through the respective central magnetic field conductor upwards to a housing cover. This measure supports the ability to drive over the base assembly. The base plate is then expediently configured to be flat, wherein the base plate extends in a plane running perpendicular to the housing height direction.When the base assembly is assembled, the base plate typically rests on a flat and horizontally aligned surface, so that the housing height direction corresponds to the vertical direction or the direction of gravity. The housing can be conveniently configured as a cuboid, defining a housing longitudinal direction, a housing transverse direction, and the housing height direction, which are perpendicular to each other.

[0018] In this context, the relative location specifications "top" and "bottom" refer to the housing height direction, so "top" or "above" is directed away from the base plate, while "bottom" or "below" is directed toward the base plate. The relative direction specification "lateral" then corresponds to an orientation perpendicular to the housing height direction.

[0019] According to another advantageous embodiment, at least four rectangular central magnetic field conductors can be arranged in the central region of the housing interior, with the respective central cooling channel extending between two central magnetic field conductors. In this way, the heat from the central magnetic field conductors can also be dissipated via the cooling air.

[0020] In an advantageous further development, two central cooling channels can be provided, which are spaced apart from each other in the transverse direction of the housing and each pass between two central magnetic field conductors in the longitudinal direction of the housing. This allows for a comparatively large volume flow for the cooling air to be achieved with a compact design.

[0021] In another advantageous embodiment, a coil carrier plate can be arranged in the housing interior above the magnetic field conductors, the underside of which is supported directly or indirectly on the magnetic field conductors and the respective energy coil is arranged recessed in the upper side of which. Such a coil carrier plate can be designed to be comparatively stable and rigid in order to be able to transfer a compressive load to the magnetic field conductors when traveling over the base assembly. In addition, a stiffening plate can be arranged in the housing interior above the coil carrier plate, the underside of which is supported on the coil carrier plate and on the upper side of which a cover plate of the housing is supported. The cover plate of the housing forms the housing cover, i.e. the upper outer contour of the housing. The cover plate is connected to the base plate via a side wall of the housing. The side wall delimits the housing interior laterally.To this end, the side wall runs closed around the housing interior in the direction of the housing height, allowing the cover plate to be supported on the base plate along the edges. The stiffening plate stabilizes and stiffens the housing in the area of ​​the cover plate, thus enabling compressive force to be transmitted from the cover plate via the stiffening plate to the coil support plate. This improves the housing's ability to be driven over. The coil support plate, the stiffening plate, and the cover plate are expediently made of a plastic, which can be fiber-reinforced, in particular.

[0022] According to a particularly advantageous embodiment, it can now be provided that the above-mentioned four central magnetic field conductors are arranged in a rectangular manner, wherein a central support foot is additionally provided which is supported at the bottom on the base plate, which is supported at the top on the coil carrier plate and / or on the stiffening plate, and which extends centrally between the central magnetic field conductors. With the help of this additional central support foot, the housing can be significantly stabilized in the central region, which improves its ability to be driven over. This additional support foot can be made of a fiber-reinforced plastic. In contrast, the support feet, which each support a magnetic field conductor on the base plate, can be made of a metal, preferably aluminum.

[0023] In another embodiment, the central additional support foot can be arranged transversely across the housing between the two aforementioned central cooling channels. This supports a compact design.

[0024] Another embodiment proposes that the respective upper cooling channel be formed in the stiffening plate and be open on the underside of the stiffening plate. The downwardly open upper cooling channel can be covered, in particular, by the coil support plate. In any case, the cooling air guided in the upper cooling channel can be in direct contact with the respective power coil. This allows heat to be dissipated from the power coil particularly easily and efficiently. The respective upper cooling channel is integrated into the stiffening plate by groove-shaped recesses on the underside of the stiffening plate.

[0025] In another embodiment, the housing can be rectangular, so that the edge region of the housing interior has two longitudinal sections and two transverse sections, which are connected to one another via four corner regions. The respective heat transfer chamber can then expediently be formed in a corner region of the edge region, such that the respective heat transfer chamber extends along a portion of one of the longitudinal sections and along a portion of one of the transverse sections. Thus, the heat transfer chamber extends relatively far along the edge region, so that a correspondingly large portion of the base plate collar is assigned to it.

[0026] According to an advantageous embodiment, the respective cooling circuit can have two edge-side cooling channels, one of which is arranged within the corner region in the longitudinal section, while the other is arranged within the corner region in the transverse section. This allows the two edge-side cooling channels to open into the respective heat transfer chamber at a relatively large distance from each other, thereby enabling a comparatively long residence time of the cooling air within the heat transfer chamber, which promotes heat transfer from the cooling air to the base plate.

[0027] According to another embodiment, the respective edge-side cooling channel can be funnel-shaped, so that an inlet cross-section communicating with the respective upper cooling channel is larger than an outlet cross-section communicating with the respective heat transfer chamber. This accelerates the flow of cooling air at the respective edge-side cooling channel, which can be used for improved heat transfer in the respective heat transfer chamber. At the same time, a reduced flow velocity and thus a longer residence time are achieved in the respective upper cooling channel, which promotes heat transfer there.

[0028] In another advantageous embodiment, the respective cooling circuit can have several upper cooling channels that branch off at the respective central cooling channel and through which cooling air flows in parallel during operation of the cooling circuit. This allows a comparatively large area above the respective power coil to be covered by the upper cooling channels, which promotes heat dissipation.

[0029] According to an advantageous development, at least two upper cooling channels can be converged at at least one edge-side cooling channel. Converging the air flow into one edge-side cooling channel promotes the inflow of cooling air to the respective heat transfer chamber. In particular, this allows for comparatively long flow paths for the cooling air within the respective heat transfer chamber, thus allowing for a comparatively long residence time.

[0030] In another advantageous embodiment, all magnetic field conductors can each be thermally supported on the base plate via a support foot. In this case, the respective support foot is supported on the respective magnetic field conductor in a support area in a heat-transferring manner. In a particularly advantageous embodiment, at least one such support area is located centrally below the associated magnetic field conductor. The support feet can be made of a thermally conductive material, preferably of a metal, in particular aluminum. Furthermore, the support feet can be connected to the respective magnetic field conductor in a heat-transferring manner, for example, welded, glued, or soldered thereto. The use of a thermally conductive material for the heat-transferring coupling between the support foot and the magnetic field conductor is also conceivable. Such a thermally conductive material can, for example, be designed as a TIM, where TIM stands for Thermal Interface Material.In particular, the TIM can be formed by a thermally conductive paste or thermally conductive foil or the like. Each support region has a projection running parallel to the housing height direction. The respective upper cooling channel can then expediently be routed laterally around the projections of the support regions and / or between two adjacent projections. This design excludes the support regions from the course of the upper cooling channels. In particular, these projections can extend continuously in the housing height direction through the coil support plate and through the stiffening plate to the cover plate. This allows the support forces that propagate in the housing height direction along the projections to be transmitted unhindered from the base plate to the cover plate.In another advantageous embodiment, the respective lower cooling channel can have a longitudinal section running along the base plate, which is open at the bottom and covered by the base plate, so that the cooling air flowing in the respective lower cooling channel is in direct contact with the base plate. This improves the heat transfer between the cooling air and the base plate.

[0031] Additionally or alternatively, the respective lower cooling channel can have a longitudinal section running along at least one of the magnetic field conductors, which is open at the top and covered by the at least one magnetic field conductor, so that the cooling air flowing in the respective lower cooling channel is in direct contact with the at least one magnetic field conductor. In this way, the heat transfer between the cooling air and the respective magnetic field conductor can be improved.

[0032] In an advantageous embodiment, at least two cooling circuits can be formed in the housing interior, each of which is assigned a common central cooling channel that connects the lower cooling channels of the two cooling circuits with the upper cooling channels of the two cooling circuits. The essentially closed cooling circuits are coupled to one another by the common central cooling channel, so that cooling air from one cooling circuit can also reach the other cooling circuit via the common central cooling channel, and vice versa. The use of a common central cooling channel promotes a compact design and avoids large temperature differences in the circulating cooling media of the two cooling circuits. This allows the stationary induction charging device to be cooled homogeneously.

[0033] In another embodiment, exactly four cooling circuits can be formed in the housing interior. In particular, in the case of a cuboid-shaped housing or a rectangular housing, a heat transfer chamber can be assigned to each corner region of the housing, which is integrated into one of the four cooling circuits. In principle, it is conceivable to assign a common central cooling channel to the four cooling circuits, so that all four cooling circuits are fluidically coupled to one another. However, an embodiment is preferred in which exactly two central cooling channels are assigned to the four cooling circuits, which form a central cooling channel for each two cooling circuits, which connects the lower cooling channels of the two associated cooling circuits with the upper cooling channels of the two associated cooling circuits.The four cooling circuits thus form two pairs of cooling circuits, with the cooling circuit pairs being fluidically decoupled from each other, while the two cooling circuits of each cooling circuit pair are fluidically coupled to each other via the respective shared central cooling channel. The use of two separate central cooling channels facilitates the arrangement of the aforementioned additional central support foot, which promotes the stabilization of the housing in the central area.

[0034] An inductive vehicle charging system according to the invention comprises a floor assembly of the type described above and a vehicle assembly configured for mounting on a battery-electric vehicle. Furthermore, the vehicle charging system is configured for charging a vehicle battery with electrical energy for inductive energy transfer between the floor assembly and the vehicle assembly.

[0035] Further important features and advantages of the invention emerge from the subclaims, from the drawings and from the associated description of the figures based on the drawings.

[0036] It is understood that the features mentioned above and those to be explained below can be used not only in the respective combination specified, but also in other combinations or on their own, without departing from the scope of the invention defined by the claims. Components mentioned above and to be mentioned below of a higher-level unit, such as a device, apparatus, or arrangement, which are designated separately, may form separate parts or components of this unit or be integral areas or sections of this unit, even if this is shown differently in the drawings.

[0037] Preferred embodiments of the invention are illustrated in the drawings and are explained in more detail in the following description, wherein the same reference numerals refer to the same or similar or functionally identical components.

[0038] They show, schematically,

[0039] Figure 1 shows a highly simplified longitudinal section of a floor assembly,

[0040] Figure 2 shows a highly simplified vertical section of the floor assembly below magnetic field conductors,

[0041] Figure 3 shows a highly simplified elevation section of the floor assembly above an energy coil

[0042] Figure 4 shows a highly simplified cross-section in the region of a lower cooling channel in various embodiments and / or longitudinal sections A, B, Figure 5 shows a simplified longitudinal section of the base assembly in another embodiment,

[0043] Figure 6 shows a simplified longitudinal section of the floor assembly in a further embodiment,

[0044] Figure 7 shows a highly simplified vertical section in the area of ​​a support foot for different embodiments A, B, C, D

[0045] Figure 8 shows a highly simplified cross-section of the support foot according to section lines VIII in Figure 7 for various embodiments A, B, C, D.

[0046] According to Figure 1, an inductive vehicle charging system 1 comprises a floor assembly 2 and a vehicle assembly 3. In the assembled state of the vehicle charging system 1, the floor assembly 2 is mounted on a base 4, while the vehicle assembly 3 is mounted on a battery-electric vehicle 5, only partially shown here. The battery-electric vehicle 5 has a vehicle battery 6, which is coupled to the vehicle assembly 3, in particular via a charging device not shown here. The vehicle charging system 1 is configured such that it enables an inductive energy transfer between the floor assembly 2 and the vehicle assembly 3 for charging the vehicle battery 6 with electrical energy.

[0047] According to Figures 1 to 3, 5, and 6, the base assembly 2 comprises a housing 7, a base plate 8, at least one energy coil 9, a plurality of magnetic field conductors 10, and at least one cooling circuit 11. The housing 7 has a housing interior 12. The base plate 8 is configured for fixed placement on the substrate 4 and delimits the housing interior 12 at the bottom. Furthermore, the base plate 8 is dimensioned such that it protrudes laterally beyond the housing 7 with a peripheral, circumferential collar 13, i.e., transversely to the housing height direction Z.

[0048] The housing 7 is configured cuboidally and rectangularly, so that it defines a housing longitudinal direction X, a housing transverse direction Y, and a housing vertical direction Z, which run perpendicular to one another. In Figures 1, 5, and 6, the housing transverse direction Y extends perpendicular to the drawing plane. In Figures 2 and 3, the housing vertical direction Z extends perpendicular to the drawing plane.

[0049] The base plate 8 is expediently designed to be flat, with the plane of the base plate 8 running perpendicular to the housing height direction Z. The housing 7 further has a housing cover 14, which is spaced from the base plate 8 with respect to the housing height direction Z and is formed in the example by a cover plate 15. The cover plate 15 is expediently configured to be flat and extends in a plane running perpendicular to the housing height direction Z. The housing cover 14 or the cover plate 15 delimits the housing interior 12 at the top. Furthermore, the housing 7 has a surrounding housing wall 16, which supports the housing cover 14 or the cover plate 15 on the base plate 8. Heat-conducting elements 17 can be arranged on the collar 13 for heat transfer, for example in the form of heat-conducting fins. The heat-conducting elements 17 increase the surface area of ​​the collar 13 that is available for heat transfer to an environment 18 or to the ambient air contained therein.

[0050] The power coil 9 serves to generate an alternating electromagnetic field for inductive energy transmission. Each power coil 9 can be formed by at least one copper strand. The magnetic field conductors 10 serve to shield the alternating field generated by the respective power coil 9 and radiated downwards and redirect it upwards, thereby improving or amplifying the upward radiation of the alternating field. For this purpose, the magnetic field conductors 10 are arranged between the base plate 8 and the power coil 9 with respect to the housing height direction Z. They are expediently configured to be flat and extend in a plane that runs perpendicular to the housing height direction Z.

[0051] The respective cooling circuit 11 serves at least to cool the magnetic field conductors 10 and the power coil 9. It is clear that other components of the base assembly 2 requiring cooling can also be cooled using the respective cooling circuit 11, such as components of a power electronics system not shown here. During operation of the cooling circuit 11, cooling air 19 circulates in the cooling circuit 11. The circulation of the cooling air 19 or the flow of the cooling air 19 is indicated by arrows in Figures 1 to 3, 5 and 6. The respective cooling circuit 11 each has at least one fan 20 for driving the cooling air 19. The power coil 9, the magnetic field conductors 10 and the respective cooling circuit 11 are arranged in the housing interior 12.

[0052] The base assembly 2 expediently has several such cooling circuits 11 in the housing interior 12. Two such cooling circuits 11 are visible in the sectional view of Figure 1. Four such cooling circuits 11 are visible in the sectional views of Figures 2 and 3. The following explanations regarding the specific design of the respective cooling circuit 11 are explained in more detail using one such cooling circuit 11, but apply equally to all cooling circuits 11 shown here.

[0053] According to Figures 1 to 3, 5 and 6, the respective cooling circuit 11 has at least one heat transfer chamber 21 through which the cooling air 19 can flow, which is formed in an edge region 22 of the housing interior 12 and which is delimited by the base plate 8. In other words, the heat transfer chamber 21 is formed directly on the base plate 8 in the edge region 22. Within the heat transfer chamber 21, heat-conducting elements 49 can be arranged on the base plate 8, which improves the heat transfer from the cooling air within the heat transfer chamber 21 to the base plate. The heat-conducting elements 49 can be designed as ribs and, according to Figure 2, can optionally also be shaped so that they also serve to guide the flow.

[0054] In Figure 1, a heat dissipation 50, which occurs in the area of ​​the collar 13 in the base plate 8, is indicated by arrows. As can be seen, heat is introduced into the respective heat transfer chamber 21, in particular via the heat-conducting elements 49, from the cooling air 19 into the base plate 8 and transferred from the housing 7 into the collar 13. From the collar 13, the heat is transferred to the environment 18. At the same time, heat is also introduced from the base plate 8 into the substrate 4.

[0055] The respective cooling circuit 11 also has at least one lower cooling channel 23, which guides the cooling air 19 below the magnetic field conductors 10 from the respective heat transfer chamber 21 to a central region 24 of the housing interior 12, bordered by the edge region 22. The respective cooling circuit 11 also has at least one upper cooling channel 25, which guides the cooling air 19 above the power coil 9 from the central region 24 to the edge region 22. The respective cooling circuit 11 now also has at least one central cooling channel 26 and at least one edge cooling channel 27. The central cooling channel 26 guides the cooling air 19 in the central region 24 from the respective lower cooling channel 23 to the respective upper cooling channel 25. The respective edge cooling channel 27 guides the cooling air 19 in the edge region 22 from the respective upper cooling channel 25 to the respective heat transfer chamber 21.Accordingly, the cooling air 19 circulates as follows during operation of the cooling circuit 11 according to the exemplary embodiments shown here. The fan 20 draws in the cooling air 19 from the heat transfer chamber 21 and conveys it through the respective lower cooling channel 23 to the central cooling channel 26, which redirects the cooling air 19 into the respective upper cooling channel 25. The respective upper cooling channel 25 for the cooling air 19 then leads to the respective peripheral cooling channel 27, which returns the cooling air 19 to the heat transfer chamber 21, thereby closing the cooling circuit 11. In the examples shown, the respective fan 20 is arranged directly downstream of the respective heat transfer chamber 21. The fan 20 is thus exposed to minimized thermal stress. In principle, however, any other positioning of the fan 20 within the respective cooling circuit 11 is also possible, preferably in one of the cooling channels 23, 25, 26.

[0056] The sectional view in Figure 2 shows how the cooling air 19 flows from the respective heat transfer chamber 21 through the respective lower cooling channel 23 to the respective central cooling channel 26 below the magnetic field conductor 10. The sectional view in Figure 3 shows how the cooling air 19 flows from the respective central cooling channel 26 above the energy coil 9 through the upper cooling channels 25 to the edge cooling channels 27. From there, the cooling air 19 then returns to the respective heat transfer chamber 21.

[0057] In the exemplary embodiment shown here, the magnetic field conductors 10 are each rectangular and flat. The magnetic field conductors 10 are all arranged in a plane that runs perpendicular to the housing height direction Z. According to Figures 2 and 3, exactly four magnetic field conductors 10 are provided in the central region 24, which are also referred to below as central magnetic field conductors 10'. These central magnetic field conductors 10' are subject to particularly high thermal loads during operation of the base assembly 2. All other magnetic field conductors 10 are arranged around the central magnetic field conductors 10' and extend along the edge region 22. All magnetic field conductors 10 are each supported in a heat-conducting manner on the base plate 8 via a support foot 28. The respective support foot 28 is expediently made of a metal, preferably aluminum, and can be soldered, glued, or welded to the metallic base plate 8.According to Figures 1, 2, and 5 to 8, the support feet 28 associated with a central magnetic field conductor 10' can each be integrated into one of the lower cooling channels 23, specifically such that the cooling air 19 flows against and / or around and / or through the respective support foot 28. As a result, the support foot 28, which is thermally coupled to the respective central magnetic field conductor 10', is cooled by means of the cooling air 19, which promotes heat dissipation from the central magnetic field conductors 10'.

[0058] Figures 7 and 8 show different variants A, B, C, and D for the flow onto, around, or through these support feet 28 as examples and in a highly simplified manner. For example, Figures 7A and 8A show a flow through the respective support foot 28. For this purpose, the support foot 28 can have a channel 29 that is connected to the respective lower cooling channel 23 such that the cooling air 19 flows through this channel 29. In the example of Figures 7A and 8A, heat-conducting elements 30 in the form of ribs and fins are provided in the channel 29, by means of which the surface area of ​​the support foot 28 available for heat transfer is significantly increased.

[0059] In the example of Figures 7B and 8B, the cooling air 19 flows around the support foot 28. For this purpose, the respective lower cooling channel 23 has a corresponding extension 31, which is dimensioned such that the desired flow around the support foot 28, which is solid in this case, is achieved.

[0060] Figures 7C and 8C also show a flow around the support foot 28, in which, however, in contrast to the embodiment shown in Figures 7B and 8B, heat conducting elements 32 are formed on the outside of the support foot 28, which are arranged in the extension 31 of the lower cooling channel 23 and enlarge the surface available for heat transfer.

[0061] In the embodiment shown in Figures 7D and 8D, the respective support foot 28 again has a channel 33 that is integrated into the lower cooling channel 23. A heat-conducting element 34 designed as a flow barrier is arranged in this channel 33. This heat-conducting element is connected laterally, i.e., transversely to the housing height direction Z, to the support foot 28 and at the bottom to the base plate 8 in a heat-transfer manner. According to Figure 8D, the channel 33 is configured such that it widens in the housing height direction Z relative to the lower cooling channel 23 and projects into the support foot 28.

[0062] The respective support foot 28 is supported on the respective magnetic field conductor 10 according to Figures 2 and 3 in a support region 35. In the example shown here, the support feet 28 each have a circular cross-section transverse to the housing height direction Z. Accordingly, the support regions 35 are circular in design here. It is clear that other cross-sections for the support feet 28 can also be considered, in particular rectangular cross-sections that are adapted to the contour of the rectangular magnetic field conductor 10. The support regions 35 or their contour defines a projection 36 running parallel to the housing height direction Z, which is indicated in Figure 3 with a broken line. According to Figure 3, the upper cooling channels 25 are guided laterally around the projections 36 of the support regions 35, i.e. transverse to the housing height direction Z.According to Figure 3, this applies both to the support feet 28 of the four central magnetic field conductors 10' and to the support feet 28 of the magnetic field conductors 10 arranged along the edge region 22. It can also be seen how the upper cooling channels 25 are each routed between two projections 36 of support regions 35 of adjacent support feet 28. Thus, all support regions 36 are omitted from the upper cooling channels 25.

[0063] If, as here, four rectangular central magnetic field conductors 10' are provided, which are arranged in the central region 24, it can be expediently provided that the respective central cooling channel 26 is routed between two central magnetic field conductors 10'. If, as in the examples in Figures 2 and 3, two central cooling channels 26 are provided, they are spaced apart from one another in the transverse direction Y of the housing and each pass between two central magnetic field conductors 10' in the longitudinal direction X of the housing.

[0064] The embodiment shown here is preferred, in which, according to Figure 1, a coil support plate 37 is arranged in the housing interior 12 above the magnetic field conductor 10, which coil support plate is expediently configured flat and extends in a plane running transversely to the housing height direction Z. The coil support plate

[0065] 37 is supported directly or indirectly with its underside on the magnetic field conductors 10. Figures 1, 5 and 6 show an indirect support of the coil support plate 37 on the magnetic field conductors 10, each of which has a support body

[0066] 38. This can preferably be a thermally conductive material, in particular a TIM. The thermally conductive material is preferably a non-metallic material, in particular a ceramic material or a plastic material. The coil carrier plate 37 carries the respective energy coil 9 on its upper side. For this purpose, the coil carrier plate 37 can have a recess on its upper side in which the energy coil 9 is arranged in a recessed manner. In particular, it can be provided that the recess is designed to be complementary to the energy coil 9. For example, in the case of a spiral-shaped energy coil 9, the recess can also be designed to be spiral-shaped.

[0067] According to Figure 1, a stiffening plate 39 can also be arranged in the housing interior 12, which extends above the coil support plate 37. The stiffening plate 39 can also be configured flat and extend in a plane that runs perpendicular to the housing height direction Z. The stiffening plate 39 is supported with its underside on the coil support plate 37. The cover plate 15 or the housing cover 14 is supported on the upper side of the stiffening plate 39. This ensures continuous support of the housing cover 14 or the cover plate 15 on the base plate 8. The housing cover 14 or the cover plate 15 is supported via the stiffening plate 39 on the coil support plate 37, which is supported via the support elements 38 on the magnetic field conductors 10, which in turn are supported on the base plate 8 via the support feet 28.

[0068] In the example shown here, an additional central support foot 40 is also provided, which is supported at the bottom on the base plate 8 and at the top on the coil support plate 37 and / or the stiffening plate 39. For example, the coil support plate 37 can have a through-hole in the area of ​​the additional support foot 40, so that the additional support foot 40 can extend through the coil support plate 37 to the stiffening plate 39. It is also conceivable for the additional support foot 40 to have a collar (not shown here), via which the coil support plate 37 can also be supported on the additional support foot 40. In any case, in the examples shown here, the additional support foot 40 is guided centrally between the four central magnetic field conductors 10', which are also arranged rectangularly here. Furthermore, the central support foot 40 is located, according to Figures 2 and 3, between the two central cooling channels 26 with respect to the transverse direction Y of the housing.

[0069] The respective upper cooling channel 25 can be formed in the stiffening plate 39. The respective upper cooling channel 25 is expediently open on the underside of the stiffening plate 39 and can, in particular, be covered by the coil support plate 37. In any case, the cooling air 19 flowing in the respective upper cooling channel 25 can be in direct contact with the respective power coil 9.

[0070] According to Figures 2 and 3, the housing 7 can expediently be configured rectangularly, whereby the edge region 22 of the housing interior 12 has two longitudinal sections 41 running parallel to the housing longitudinal direction X and two transverse sections 42 running parallel to the housing transverse direction Y. Furthermore, four corner regions 43 are formed in the edge region 22. The respective heat transfer chamber 21 is now formed in such a corner region 43 in such a way that it extends along a part of a longitudinal section 41 adjoining this corner region 43 and along a part of a transverse section 42 adjoining this corner region 43. Furthermore, it is provided here that the respective cooling circuit 11 has two edge-side cooling channels 27. One edge-side cooling channel 27 is arranged within the corner region 43 in the longitudinal section 41, while the other edge-side cooling channel 27 is arranged within the corner region 43 in the transverse section 42.In the simplified sectional view of Figure 1, the section is selected such that both the edge-side cooling channel 27 arranged in the longitudinal section 41 and the edge-side cooling channel 27 arranged in the transverse section 42 can be seen. According to Figures 1 to 3, it can now also be provided that the respective edge-side cooling channel 27 is designed funnel-shaped, such that the respective edge-side cooling channel 27 has an inlet cross-section 44 communicating with the respective upper cooling channel 25 and an outlet cross-section 45 communicating with the respective heat transfer chamber 21, which is smaller than the associated inlet cross-section 44. The funnel-shaped contour can be seen in Figure 1. The inlet cross-sections 44 can be seen in Figures 1 and 3. The outlet cross-sections 45 can be seen in Figures 1 and 2.

[0071] According to Figure 3, the respective cooling circuit 11 has a plurality of upper cooling channels 25, which branch off at the respective central cooling channel 26 and through which the cooling air 19 flows in parallel. Flow guide elements 48 can be arranged in the upper cooling channels 25. These flow guide elements 48 can also simultaneously serve for heat transfer. Additionally or alternatively, the flow guide elements 48 can also be configured to enable a pressure force transmission from the stiffening plate 39 to the coil support plate 37.

[0072] According to Figure 3, two upper cooling channels 25 can be merged at the respective edge-side cooling channel 27. In the example in Figure 3, the respective cooling circuit 11 branches off at the associated central cooling channel 26 into a total of four upper cooling channels 25, which are then rejoined in pairs at the two edge-side cooling channels 27. As can be seen, the upper cooling channels 25 lead away from the respective central cooling channel 26 from the central region 24 and branch off there into the individual upper cooling channels 25, so that they can run over a comparatively large area there. The upper cooling channels 25 are routed around the projections 36 of the support regions 35 or through between adjacent projections 36. According to Figures 4A and 4B, the respective lower cooling channel 23 can have longitudinal sections with different cross-sectional geometries. Figure 4A shows a cross-section that is open on one side. Figure 4B shows a closed cross-section.Depending on the positioning of the respective lower cooling channel 23, the open cross-section according to Figure 4A can be closed by another component, for example by the base plate 8 or by a magnetic field conductor 10. The closed cross-section according to Figure 4B can extend adjacent to another component, for example adjacent to the base plate 8 or adjacent to a magnetic field conductor 10.

[0073] According to Figures 5 and 6, the respective lower cooling channel 23 can have a longitudinal section 46 that runs along at least one of the magnetic field conductors 10. This longitudinal section 46 can, as shown in Figure 4A, be open at the top and covered by the respective magnetic field conductor 10. The cooling air 19 flowing in the lower cooling channel 23 can now be in direct contact with the respective magnetic field conductor 10. According to Figure 6, the respective lower cooling channel 23 can optionally have a longitudinal section 47 that runs along the base plate 8 and, as shown in Figure 4A, is open at the bottom and covered by the base plate 8. The cooling air 19 flowing in the lower cooling channel 23 can now be in direct contact with the base plate 8.

[0074] In the embodiment shown here, as mentioned, exactly four cooling circuits 11 are formed. Since only two central cooling channels 26 are provided here, each pair of cooling circuits 11 forms a cooling circuit pair, each of which is assigned a common central cooling channel 26. Figures 2 and 3 show a lower cooling circuit pair and an upper cooling circuit pair. The respective common central cooling channel 26 connects the lower cooling channels 23 of the two cooling circuits 11 of the respective cooling circuit pair with the upper cooling channels 25 of the two cooling circuits 11 of the respective cooling circuit pair.While the respective cooling circuit 11 has a plurality of upper cooling channels 25, in the examples shown here, only one lower cooling channel 23 is provided in the respective cooling circuit 11, which, in a rectangular housing 2, runs essentially diagonally, namely from the corner region 43, in which the heat transfer chamber 21 is located, towards the central region 24, in which the respective central cooling channel 26 is located. In this exemplary embodiment, the associated fan 20 is arranged in the respective lower cooling channel 23. In the examples shown here, the support foot 28 of the respective central magnetic field conductor 10' is integrated into the respective lower cooling channel 23. According to Figures 1, 2 and 6, the fan 20 is arranged upstream of the respective support foot 28 with respect to the flow direction of the cooling air 19. In contrast, Figure 5 shows a variant in which the fan 20 is arranged downstream of the respective support foot 28.

[0075] *****

Claims

Claims 1. Floor assembly (2) for an inductive vehicle charging system (1) which is designed to charge a vehicle battery (6) with electrical energy for inductive energy transfer between the floor assembly (2) and a vehicle assembly (3), - with a housing (7) having a housing interior (12), - with a base plate (8) for placement on a base (4), which delimits the housing interior (12) downwards and which projects laterally beyond the housing (7) with a collar (13), - with at least one energy coil arranged in the housing interior (12) (9) for generating an alternating electromagnetic field for inductive energy transfer, - with several magnetic field conductors arranged in the housing interior (12) (10) arranged between the base plate (8) and the energy coil (9), - with at least one cooling circuit (11) formed in the housing interior (12) for cooling the magnetic field conductors (10) and the energy coil (9), in which cooling air (19) circulates and which has at least one fan (20) for driving the cooling air (19), characterized in - that the respective cooling circuit (11) has at least one heat transfer chamber (21) through which the cooling air (19) flows, which heat transfer chamber is formed in an edge region (22) of the housing interior (12) and is delimited by the base plate (8).

2. Floor assembly (2) according to claim 1, characterized in that - that the respective cooling circuit (11) has at least one lower cooling channel (23) which guides the cooling air (19) below the magnetic field conductors (10) from the respective heat transfer chamber (21) to a central region (24) of the housing interior (12), - that the respective cooling circuit (11) has at least one upper cooling channel (25) which directs the cooling air (19) above the energy coil (9) from the central area (24) of the housing interior (12) to the edge region (22) of the housing interior (12), - that the respective cooling circuit (11) has at least one central cooling channel (26) which guides the cooling air (19) in the central region (24) of the housing interior (12) from the respective lower cooling channel (23) to the respective upper cooling channel (25) leads, - that the respective cooling circuit (11) has at least one edge-side cooling channel (27) which guides the cooling air (19) in the edge region (22) of the housing interior (12) from the respective upper cooling channel (25) to the respective heat transfer chamber (21).

3. Floor assembly (2) according to claim 2, characterized in - that at least one of the magnetic field conductors (10) forms a central magnetic field conductor (10') which is arranged in the central region (24) of the housing interior (12) and is supported in a heat-conducting manner on the base plate (8) via a support foot (28), - that the respective support foot (28) is integrated into the respective lower cooling channel (23) in such a way that the cooling air (19) flows towards and / or around and / or through the respective support foot (28) for heat transfer.

4. Floor assembly (2) according to claim 3, characterized in - that the respective support foot (28) is supported on the respective central magnetic field conductor (10') in a heat-transferring support area (35), - that the respective upper cooling channel (25) is guided laterally around a projection (36) of the support region (35) running parallel to the housing height direction (Z).

5. Floor assembly (2) according to one of claims 2 to 4, characterized in that - that at least four rectangular central magnetic field conductors (10') are arranged in the central region (22) of the housing interior (12), - that the respective central cooling channel (26) is passed between at least two central magnetic field conductors (10').

6. Floor assembly (2) according to claim 5, characterized in - that two central cooling channels (26) are provided, which are spaced apart from one another in the transverse direction (Y) of the housing and are each guided between two central magnetic field conductors (10') in the longitudinal direction (X) of the housing.

7. Floor assembly (2) according to one of the preceding claims, characterized in - that in the housing interior (12) above the magnetic field conductors (10) there is arranged a coil carrier plate (37), which is supported with its underside directly or indirectly on the magnetic field conductors (10) and in whose upper side the respective energy coil (9) is arranged in a recess, - that in the housing interior (12) above the coil support plate (37) there is arranged a stiffening plate (39), which is supported with its underside on the coil support plate (37) and on whose upper side a cover plate (15) of the housing (7) is supported.

8. Floor assembly (2) according to claims 5 and 7, characterized in that - that the at least four central magnetic field conductors (10') are arranged rectangularly, - that a central additional support foot (40) is provided which is supported at the bottom on the base plate (8), which is supported at the top on the coil support plate (37) and / or on the stiffening plate (39) and which is guided centrally between the central magnetic field conductors (10').

9. Floor assembly (2) according to claims 6 and 8, characterized in that - that the central additional support foot (40) is arranged in the transverse direction (Y) of the housing between the two central cooling channels (26).

10. Floor assembly (2) according to one of claims 7 to 9, characterized in that - that the respective upper cooling channel (25) is formed in the stiffening plate (39) and is open on the underside of the stiffening plate (39) and is covered by the coil support plate (37), so that the cooling air (19) is in direct contact with the respective energy coil (9).

11. Floor assembly (2) according to one of the preceding claims, characterized in that - that the housing (7) is rectangular, so that the edge region (22) of the housing interior (12) has two longitudinal sections (41) and two transverse sections (42), - that the respective heat transfer chamber (21) is formed in a corner region (43) of the edge region (22) and extends along a part of one of the longitudinal sections (41) and along a part of one of the transverse sections (42).

12. Floor assembly (2) according to claim 11, characterized in that - that the respective cooling circuit (11) has two edge-side cooling channels (27), one of which is arranged within the corner region (43) in the longitudinal section (41), while the other is arranged within the corner region (43) in the transverse section (42).

13. Floor assembly (2) according to claim 2 or according to claim 2 and according to one of claims 3 to 12, characterized in that - that the respective edge-side cooling channel (27) is funnel-shaped, so that an inlet cross-section (44) communicating with the respective upper cooling channel (25) is larger than an outlet cross-section (45) communicating with the respective heat transfer chamber (21).

14. Floor assembly (2) according to claim 2 or according to claim 2 and according to one of claims 3 to 13, characterized in that - that the respective cooling circuit (11) has a plurality of upper cooling channels (25) which branch off at the respective central cooling channel (26) and through which the cooling air (19) flows in parallel.

15. Floor assembly (2) according to claim 14, characterized in - that at least two upper cooling channels (25) are brought together at at least one edge-side cooling channel (27).

16. Floor assembly (2) according to one of the preceding claims, characterized in that - that the magnetic field conductors (10) are each supported in a heat-conducting manner on the base plate (8) via a support foot (28), - that the respective support foot (28) is supported on the respective magnetic field conductor (10) in a heat-transferring support area (35), - that each support region (35) has a projection (36) running parallel to the housing height direction (Z), - that the respective upper cooling channel (25) is guided laterally around the projections (36) of the support regions (35) and / or is guided between two adjacent projections (36).

17. Floor assembly (2) according to claim 2 or according to claim 2 and according to one of claims 3 to 16, characterized in that - that the respective lower cooling channel (23) has a longitudinal section (47) running along the base plate (8), which is open at the bottom and is covered by the base plate (8), so that the cooling air (19) is in direct contact with the base plate (8).

18. Floor assembly (2) according to claim 2 or according to claim 2 and according to one of claims 3 to 17, characterized in that - that the respective lower cooling channel (23) has a longitudinal section (46) running along at least one of the magnetic field conductors (10), which is open at the top and is covered by the at least one magnetic field conductor (10), so that the cooling air (19) is in direct contact with the at least one magnetic field conductor (10).

19. Floor assembly (2) according to claim 2 or according to claim 2 and according to one of claims 3 to 18, characterized in that - that at least two cooling circuits (11) are formed in the housing interior (12), to which a common central cooling channel (26) is assigned, which connects the lower cooling channels (23) of the two cooling circuits (11) with the upper cooling channels (25) of the two cooling circuits (11).

20. Floor assembly (2) according to claim 19, characterized in - that exactly four cooling circuits (11) are formed in the housing interior (12), to which two central cooling channels (26) are assigned, - that the two central cooling channels (26) for each two cooling circuits (11) form a common central cooling channel (26) which connects the lower cooling channels (23) of the two cooling circuits (11) with the upper cooling channels (25) of the two cooling circuits (11).

21. Inductive vehicle charging system (1 ), - with a floor assembly (2) according to one of the preceding claims, - with a vehicle assembly (3) which is designed for mounting on a battery-electric vehicle (5), - wherein the vehicle charging system (1) is configured to charge a vehicle battery (6) with electrical energy for inductive energy transmission between the floor assembly (2) and the vehicle assembly (3).

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