Inductive charging device

Abstract

The present invention relates to an inductive charging device (1) for an inductive vehicle charging system for charging batteries of battery electric vehicles, in particular a stationary and / or inductive inductive charging device. The inductive charging device (1) comprises at least one coil (2) for generating an alternating electromagnetic field, which extends in a plane extending perpendicular to a height direction (H) of the inductive charging device (1) and is formed with an electrical conductor path configured as strands (3). The inductive charging device (1) further comprises a coil support structure (4) made of plastic in which the strands (3) are at least partially embedded and for positioning the strands (3). The inductive charging device (1) further comprises a support structure (5) having a plurality of support elements (6) each extending along the height direction (H), which are spaced apart from one another in a longitudinal direction (L) perpendicular to the height direction (H) and which is supported in the height direction by the coil support structure (4). The inductive charging device (1) further comprises at least two, preferably a plurality of, magnetic field conductive core plates (7) made of soft magnetic material arranged at a distance from each other and extending along a longitudinal direction (L), wherein each core plate (7) is supported on at least one support element (6).

Description

[Technical field]

[0001] The present invention relates to an inductive charging apparatus for an inductive vehicle charging system for charging the battery of a battery electric vehicle. The present invention further relates to an inductive vehicle charging system comprising such an inductive charging apparatus.

[0002] A conventional inductive vehicle charging system comprises a stationary inductive charging device, which may also be referred to as a "floor assembly" or "ground assembly", which is usually arranged in a fixed position, for example in a vehicle yard and connected to a power grid, and a mobile inductive charging device, which may also be referred to as a vehicle assembly or vehicle assembly, which is arranged in the respective vehicle, in particular in the vehicle floor. The mobile inductive charging device is here coupled to the battery of the vehicle in a suitable manner, for example via a corresponding vehicle-side charging device. For charging the battery, the vehicle together with its mobile inductive charging device is positioned with respect to the stationary inductive charging device, so that electrical energy can be transferred from the stationary inductive charging device to the mobile inductive charging device by means of induction, i.e. via an alternating electromagnetic field. In an inductive vehicle charging system, a charging plug that has to be inserted into a vehicle-side charging socket can be dispensed with.

[0003] The inductive charging device has at least one coil capable of generating an alternating electromagnetic field. Such a coil may also be called an "induction coil" or a "resonator coil". Furthermore, the stationary inductive charging device may have a number of magnetic field conductive core plates made of soft magnetic material arranged below the strands in the horizontal direction. By using the core plates, the alternating electromagnetic field generated by the respective coils and also radiated downwards from the respective coils is deflected upwards, so that the alternating magnetic field radiated upwards is amplified, so to speak.

[0004] For high electrical efficiency, it is necessary that the core plate is located as close as possible to the strands, but is positioned as precisely as possible relative to the strands, so as to affect the resonance of the resonant circuit formed with the coil as little as possible, or ideally not at all. It is known to enhance conventional core plates, which are typically formed in a rectangular parallelepiped shape and therefore each have six (upper) faces, in particular two opposing end faces and four peripheral faces arranged between the two end faces, to high dimensional stability and high surface accuracy by a mechanical process of precision grinding. This is particularly necessary, since the core plates are usually manufactured in a sintering process, in which the volume of the core plate shrinks by 20-30% from the original. This shrinkage is typically performed non-uniformly, resulting in deviations in the range of 1.0%-5.0%, which also causes large irregularities in the surface properties of the core plate. That is, precision polishing of the surfaces as described above is used to combat undesirable tolerances.

[0005] However, the precision grinding process is expensive and often exceeds the manufacturing costs remaining in the core plate.

[0006] The present invention is directed to solving this problem. In particular, improved embodiments of inductive charging devices should be created which are characterized by high mechanical stability and improved inductive efficiency while at the same time reducing manufacturing costs.

[0007] This problem is solved according to the invention by the subject matter of the independent claims. Advantageous embodiments are the subject matter of the dependent claims.

[0008] The basic idea of ​​the invention is therefore that the core plates of the inductive charging device are arranged in the height direction between the strands of the coil and the support structure, with at least one of the core plates having an unpolished, i.e. precisely unpolished, surface zone. Here, the support structure on which both the strand support with the strands and the core plate are supported is preferably designed in such a way that the core plate is mounted as plane-parallel as possible, preferably exactly plane-parallel to the orientation of the strand support, despite at least one unpolished, i.e. original, surface contour. This ensures that the dispersion of the inductive properties of the coil, which depends on the position of the core plate relative to the strands of the coil, remains small, thereby affecting as little as possible, and preferably not at all, the resonance of the resonant circuit formed with the coil.

[0009] The use of the support structure ensures that the vehicle can drive over the inductive charging device without deformation and the inevitable damage or even destruction of the coil support structure, the core plate, or the strands themselves. In the solution presented here, the core plate of the inductive charging device can be supported on the support structure. This allows the high rigidity, in particular the pressure resistance, of the core plate to be utilized in order to transfer the surface-acting stresses of the coil support structure to the support structure.

[0010] Furthermore, by embedding the strands of the coil in the coil support structure, the strands are positioned with smaller tolerances, which further increases the electrical efficiency of the inductive charging device. Similarly, by using the support structure, the core plate can be oriented with smaller tolerances and thus precisely relative to the coil support structure and therefore also to the strands of the coil, despite the unpolished surface zone. This keeps the dispersion of the inductive properties of the coil, which depends on the position of the core plate relative to the strands of the coil, small. This also makes it possible to have particularly small omissions of compensation measures for ensuring a resonant circuit in the power electronics of the inductive charging device, which also entails further cost advantages.

[0011] In particular, the inductive charging device according to the invention comprises at least one coil for generating an alternating electromagnetic field, the coil being formed by means of an electrical conductor path configured as a strand, the strand also comprising a number of electrically conductive wires, and the inductive charging device can also comprise power electronics suitable for supplying the coil with energy as well as controlling the coil's drive.

[0012] The inductive charging device has a longitudinal direction, a lateral direction that runs perpendicular to the longitudinal direction, and a height direction that runs perpendicular to the longitudinal direction and perpendicular to the lateral direction. The relative location designations "upper", "lower", "upper" and "lower" here refer to the spatial orientation of the inductive charging device that the inductive charging device has during proper operation. The height direction thus runs anti-parallel to the direction of gravity, whereby the lower components are below the upper components in the direction of gravity. If an inductive charging device that is properly placed on the ground or dug or buried in the ground runs horizontally in the longitudinal and lateral directions, the height direction runs vertically, i.e. anti-parallel to the direction of gravity. In the case of an inductive charging device, the coil preferably runs in a plane that runs perpendicular to the height direction, which plane may be extended by the longitudinal and lateral directions. "Lateral" here means "perpendicular to the height direction". Correspondingly, a "lateral plane" is herein a plane extending perpendicular to the height direction.

[0013] The inductive charging device according to the invention further comprises a coil support structure made of plastic, in which the strands are at least partially embedded, for positioning the strands. In this context, the term "embedded" is understood to mean that the embedded components, i.e. the strands, are more or less surrounded by the material of the structure in which the respective components are embedded. This can be achieved by providing matching recesses or cutouts in the structure for the insertion of the respective components. It is likewise conceivable that the respective structures are injection molded or cast or glued to the respective components. The coil support structure is expediently conceived as being flat and planar.

[0014] Furthermore, the inductive charging device according to the invention comprises a support structure having a plurality of support elements each extending along a height direction, spaced apart from one another in a longitudinal direction perpendicular to the height direction and supported in the height direction on the coil support structure. The support elements may be formed elongate in the height direction. At least one support element may be formed as a support pillar.

[0015] According to the present invention, the inductive charging device further comprises at least two, preferably a plurality of magnetic field conductive core plates made of soft magnetic material, each arranged at a distance from one another and each extending along the longitudinal direction, wherein each one of the core plates is supported on at least one support element.

[0016] At least two core plates are made of a magnetically soft, preferably electrically insulating material and each have at least one unpolished surface section. Preferably, the support in the support structure is performed using the unpolished surface section. Soft magnetic materials, such as ferrite, are characterized by easy magnetization, which is expressed by a small coercive force. The relative magnetic permeability μ R For the ferrite core plates, it is preferable that μR>2, in particular μR>1.000. A suitable material is, for example, ferrite, so that the core plates made of ferrite can also be called "ferrite plates". These core plates are conceived for the purpose as being flat and planar.

[0017] The inductive charging device according to the invention presented herein can be used both as a stationary inductive charging device and as a mobile inductive charging device. In a suitable operating state as a stationary inductive charging device, the inductive charging device is arranged on the ground or dug into the ground, in particular buried, at a vehicle parking lot. In a suitable operating state as a mobile inductive charging device, the mobile inductive charging device is integrated into a vehicle.

[0018] In a preferred embodiment, at least two, preferably several and particularly preferably all of the core plates each have two end faces each having a rectangular prism-shaped geometric shape and extending perpendicular to the height direction and four peripheral faces interconnecting these two end faces.

[0019] In this embodiment, at least one of the above-mentioned faces has at least one unpolished face zone. This means that the unpolished face zone has not been surface-treated by a grinding process, in particular by means of fine grinding. Preferably, the at least one face zone forms an area proportion of more than 60%, particularly preferably more than 80%, of the respective face, i.e. of one of the four peripheral faces or of one of the two end faces. In this way, the manufacturing costs for the core plate formed in this way can be significantly reduced. If two or more of the existing core plates are so configured, the cost-saving effect is correspondingly multiplied.

[0020] Preferably, the at least one face having at least one unpolished face zone may be one of the four peripheral faces. Particularly preferably, all four peripheral faces may each have one unpolished face zone, whereby the core plate is fixed to the support structure by means of said unpolished face zones and can thereby be positioned with high precision relative to the support structure.

[0021] In another preferred embodiment, the at least one face with at least one unpolished surface zone can be one of the two end faces. Particularly preferred in this embodiment, the two end faces can be provided with at least one unpolished surface zone. These end faces make up a larger proportion of the total surface area of ​​the cuboid than the peripheral side, so that particularly large cost advantages can be obtained in this way.

[0022] According to an advantageous development, the at least one surface can have two or more unpolished surface zones, each spaced apart from one another. In this way, cost-saving effects can be increased.

[0023] In another preferred embodiment, the inductive charging device has a housing that encloses a housing interior space. The housing comprises upper and lower housing parts that are opposite each other in the height direction. The upper housing part can preferably be part of a housing pot that opens downwards of the housing. In this case, the lower housing part can be formed as a housing cover for closing the housing pot. The coil support structure, the core plate and the support structure are arranged in this embodiment in the housing interior space. Here, the support elements of the support structure are supported at the bottom on the lower housing part or housing cover, whereas the coil support structure is supported at the top opposite the housing cover on the upper housing part or housing pot. The housing cover can be formed by a bottom plate of the inductive charging device. This bottom plate or housing cover can assume an electromagnetic shielding function. For this purpose, the material of the housing cover or bottom plate can be metal, in particular expediently. In particular, the bottom plate or housing cover can be formed as a shielding sheet made of metal. In this case, the housing has electromagnetic shielding properties. Metal can be selected as material for the housing. Alternatively, by using a bottom plate or a housing cover, the inductive charging device can be placed on the ground. That is, the lower housing part can be used at or in the respective car park for the installation of the inductive charging device on the ground. The support structure can here transfer stresses in the height direction, which may occur, for example, when a car drives over the inductive charging device, from the upper housing part to the lower housing part via the coil support structure. It is also conceivable to configure the support element thermally conductive, so that additionally heat from the coil and / or core plate can be dissipated from the coil / core plate. For this purpose, the support element can be manufactured from metal or from a thermally conductive plastic.

[0024] According to an advantageous development of the inductive charging device according to the invention, a pressure element is arranged on the housing pot for each support element, which respectively projects into the housing interior space and which presses the coil support structure and the core plate against the support elements of the support structure, thus improving the stability of the structure.

[0025] In a preferred embodiment, one pressure element and one support element are opposed in the height direction, so that one core plate and one coil support structure are arranged between the coil support structure and the support structure, in this way ensuring that the mechanical load path starting from the pressure element always ends in the support element against the height direction.

[0026] Particularly preferably, the coil support structure is sandwiched between the support structure and the upper housing part or sandwiched between the core plate and the upper housing part, both variants ensuring that the coil support structure is held stably between the upper housing part and the support structure.

[0027] In a further preferred embodiment, at least one core plate is supported by two longitudinally adjacent support elements, which ensures a stable holding of the core plate in the inductive charging device and a stable positioning of the coil support structure.

[0028] According to a further advantageous development, the core plates are spaced apart from the adjacent support elements in the longitudinal direction, forming respective gaps, i.e. the distance between two adjacent support elements measured along the longitudinal direction is designed to be greater than the nominal length of the core plate in the longitudinal direction. This also allows the use of core plates with relatively high component tolerances, i.e. core plates with peripheral surfaces that are not precision ground, i.e. that are left in their original form.

[0029] Particularly preferably, a pressure element and a support element can be opposed in the height direction, so that a core plate and a coil support structure are sandwiched between the coil support structure and the support structure. This measure also improves the precise and stable positioning of the core plate relative to the coil support structure. The mechanical stability of the inductive charging device is also increased.

[0030] Particularly expediently, adjacent support elements can be provided with steps which preferably form resting surfaces on which the respective core plates rest for support in the height direction, so that the core plates can be stably held on the support structure by utilizing the gravitational effect which exists due to the weight of the core plates themselves.

[0031] Particularly preferably, the core plate can be placed on the resting surface of the respective support element along the height direction, which facilitates a mechanically stable fixing and positioning of the core plate on the respective support element, since the respective core plate is placed on the resting surface along the gravity direction.

[0032] According to another advantageous development, at least one core plate, preferably all core plates, can be fixed to the respective mounting surface by means of one, at least two, preferably at least three, particularly preferably exactly three adhesive joints. Suitable adhesives can be used to produce the adhesive joints. In this way, a permanently stable fixing and positioning of the core plates relative to the support structure and also relative to the coil carrier structure with the coil can be achieved. The adhesive joints can preferably each have an extension in the longitudinal direction of between 2 mm and 200 mm. Adhesive joints configured in this way are particularly easy to realize technically, which simplifies the manufacture of the inductive charging device. Furthermore, by using a variable adhesive thickness in the adhesive joint, a high positional accuracy of the core plate relative to the strand support can be achieved even when bonding to unpolished and therefore imprecise surface zones, which high positional accuracy is sufficient in particular to keep the dispersion of the inductive characteristics of the coil, which depends on the position of the core plate relative to the strands of the coil, small, thereby having as little or preferably no adverse effect as possible on the resonance of the resonant circuit formed using the coil.

[0033] According to another advantageous development, a positioning contour with at least one positioning element is formed on the end face of the core plate facing away from the coil support structure, in which case, for each positioning element, a complementary opposing positioning element is formed on one of the resting faces for the lateral positioning of the core plate relative to the support structure, as a result of which the core plate can be positioned very precisely in the lateral direction relative to the support structure.

[0034] Particularly expediently, the positioning elements are formed by preferably milled recesses in the end face. In this variant, therefore, a large part of the end face of the core plate facing away from the coil support structure can be formed unpolished, and preferably only a small area proportion of the milled recesses can be ground with high precision, in particular fine-ground. Thus, the effort required for fine-grounding such core plates with milled recesses is significantly reduced. Preferably, in this variant, the recesses are arranged in the outer edge section of the respective end face. Particularly preferably, at least one recess can be formed so as to open towards the edge of the core plate that defines the outer side of the edge section. These recesses can basically have any contour or geometric shape. In particular, rounded, in particular circular, or angular, in particular polygonal contours come into consideration.

[0035] In a particularly preferred embodiment, at least one core plate is supported on exactly one support element, preferably on the upper surface of the support element facing the coil support structure. This can preferably apply to all core plates of the inductive charging device. The load transfer from the upper to the lower housing part along the height direction is therefore exclusively via the associated support element. This can lead to a reduction in the bending load of the core plate and thus to a particularly large reduction in the risk of damage and / or breakage of at least one core plate. Therefore, it is particularly preferred that the respective support element is arranged centered with respect to the core plate, in particular centered with respect to the end face of the core plate facing the support element.

[0036] In a further advantageous development, a recess is formed in the end surface of at least one, preferably all, core plates facing the upper surface of the support element. This recess can be formed by milling. In this development, the assigned support element is partially received in the recess, so that the recess bottom rests on the upper surface of the support element. By using such a recess, the lateral positioning accuracy of the positioning of the core plate perpendicular to the height direction relative to the other components of the inductive charging device can be further improved. In this way, the magnetic flux guidance produced by the core plate is also optimized. Furthermore, in this variant, a large part of the end surface of the core plate facing away from the coil support structure and thus the support element remains in its original state, and preferably only a small area proportion of the milled recess can be reworked with high accuracy. The effort required for reworking such a core plate with a milled central recess is thus significantly reduced.

[0037] Particularly expediently, at least one end face of the core plate facing the support structure can be applied, in particular glued, with a positioning body, preferably made of plastic. This positioning body engages in a recess arranged on the upper surface of the respective support element, in particular here, without contacting the support element in the height direction. The cooperation of the positioning body and the recess supports a particularly accurate lateral positioning of the core plate relative to the support element and thus relative to the other components of the inductive charging device. Since the positioning body is spaced apart in the height direction from the respective holding element, it is furthermore ensured that the mechanical load path from the core plate to the support element occurs exclusively at the direct contact surface between the core plate and the support element, and that the positioning body or the positioning element remains load-free after assembly.

[0038] In a preferred embodiment, the support elements are fixed to a bottom plate which extends along the longitudinal direction and is arranged below the support structure in the height direction. The bottom plate may be formed by a housing cover of the housing of the inductive charging device. The support elements of the support structure are thus stably fixed to the housing and can be precisely oriented with respect to the coil support structure which is preferably fixed to the housing pot.

[0039] During high power operation, the coil may generate a relatively large amount of heat, which must be dissipated, in particular in order to protect the power electronics of the inductive charging device. Therefore, according to another advantageous refinement, an adapter plate can be arranged between the coil support structure and the support structure in the height direction, the upper side of which is placed on the coil support structure in a planar manner. The adapter plate can extend in the longitudinal direction and consist of a material whose thermal conductivity is greater than that of the plastic of the coil support structure. Furthermore, it can be expediently provided that the upper side of the adapter plate is in direct contact with the strands and / or that the lower side of the adapter plate is in direct contact with the core plate. This allows for improved heat transfer between the adapter plate and the strands and / or the core plate. Expediently, the material of the adapter plate is electromagnetically neutral, i.e. electrically insulating, and magnetically transparent. As already mentioned, the material of the adapter plate is preferably a relatively good heat conductor, and its thermal conductivity λ can in particular be λ>0.5 W / mK. The material of the adapter plate may in particular be a thermally conductive plastic, a ceramic or a mixture of both materials.

[0040] Particularly preferably, the end face of the core plate facing the coil support structure can be provided with a complementary recess in each case, into which a projection protruding from the coil support structure or from the adapter plate can preferably form-fittingly engage. No additional separate positional fixing is necessary in this variant, since the core plate is held positionally stable in a sandwich-like assembly of opposing side profiles which fill the two missing profiles formed by the recesses in the support element and the projections on the adapter plate.

[0041] In a further preferred embodiment, a thermal filler material is disposed on the top surface of the coil support structure opposite the core plate, which improves the dissipation of waste heat generated in the coil during operation of the inductive charging device, thereby cooling the coil.

[0042] Preferably, the thermal filler material is then in direct contact with the electronics and / or the reference plate, which leads to an even greater heat transfer between the electronics and the reference plate.

[0043] According to an advantageous development, a thermal filler material is arranged on the cover side of at least one core plate facing the coil support structure, preferably with which the coil support structure is in mechanical contact. Alternatively or additionally, in this development, the aforementioned thermal filler material can also be arranged on the cover side of at least one core plate facing away from the coil support structure, which improves the heat dissipation from the coil and thus cools the coil.

[0044] Particularly preferably, at least one, preferably all, of the four peripheral faces of at least one core plate may be arranged with the above-mentioned thermal filler material.

[0045] The thermal filler material may in all the above embodiments be formed by a thermally conductive filler or adhesive which may in particular compensate or fill existing voids, gaps etc. This is particularly advantageous for thermally bonding irregular surface contours, such as for example intact surfaces, to flat surfaces and thereby allowing conductive heat transfer.

[0046] The invention further relates to an inductive vehicle charging system according to the invention, which comprises an inductive charging device according to the invention as described above. The advantages of the inductive charging device according to the invention are therefore also transferred to the vehicle charging system according to the invention. The inductive vehicle charging system according to the invention is used for charging the battery of a battery electric vehicle. For this purpose, the vehicle charging system comprises a stationary inductive charging device according to the invention of the type described above and a mobile inductive charging device arranged in or on the vehicle. It is clear that the mobile inductive charging device of the vehicle is adapted to the stationary inductive charging device, so that with a suitable positioning of the vehicle or the mobile inductive charging device above the stationary inductive charging device, an inductive energy transfer for charging the battery can take place.

[0047] Further important features and advantages of the invention emerge from the dependent claims, the drawings and the associated description based on the drawings.

[0048] It is self-evident that the features mentioned above and those to be further described below can be used not only in the respective described combinations, but also in other combinations or alone, without departing from the scope of the present invention. The components mentioned above and those to be further described below of higher-level units, such as apparatuses, devices or assemblies shown separately, may form separate components or components of the unit, or may be integrated regions or divisions of the unit, even if shown differently in the drawings.

[0049] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention are illustrated in the drawings and will be explained in detail in the following description, in which like reference numbers refer to identical or similar or functionally identical elements. [Brief description of the drawings]

[0050] [Figure 1] FIG. 1 is a highly simplified basic cross-sectional view of a portion of a stationary inductive charging device in one embodiment. [Diagram 2] 1A-1D are highly simplified basic plan views showing schematic diagrams of parts of a stationary inductive charging device in different embodiments; [Diagram 3] 1A-1D are highly simplified, basic cross-sectional views showing parts of a stationary inductive charging device in different embodiments; [Figure 4] 1A-1D are highly simplified, basic cross-sectional views showing parts of a stationary inductive charging device in different embodiments; [Diagram 5] 1A-1D are highly simplified, basic cross-sectional views showing parts of a stationary inductive charging device in different embodiments; [Figure 6] 1A-1D are highly simplified, basic cross-sectional views showing parts of a stationary inductive charging device in different embodiments; [Figure 7] 1A-1D are highly simplified, basic cross-sectional views showing parts of a stationary inductive charging device in different embodiments; [Figure 8] 1A-1D are highly simplified, basic cross-sectional views showing parts of a stationary inductive charging device in different embodiments; [Figure 9] 1A-1D are highly simplified, basic cross-sectional views showing parts of a stationary inductive charging device in different embodiments; [Figure 10] FIG. 13 is a pictorial view clarifying the lateral arrangement of the cutouts on the cover surface of the core plate and the relative positions of the assigned presser elements.

[0051] According to figures 1 to 10, a stationary inductive charging device 1 according to the invention comprises at least one coil 2 for generating an alternating electromagnetic field.

[0052] The inductive charging device 1 here is a component of an inductive vehicle charging system which, in addition to the illustrated stationary inductive charging device 1, also comprises a mobile inductive charging device, not shown here, which is arranged on or in a battery-electric vehicle. The stationary inductive charging device described below can also be used as a mobile inductive charging device. The vehicle charging system is used to charge the batteries of a battery-electric vehicle, in which case the transmission of electrical energy takes place inductively, so that a plug-in connection between the charging station and the vehicle can be dispensed with.

[0053] The stationary inductive charging device 1 has a longitudinal direction L, a lateral direction Q extending perpendicular to the longitudinal direction L, and a height direction H extending perpendicular to the longitudinal direction L and perpendicular to the lateral direction Q.

[0054] The height direction H therefore extends antiparallel to the direction of gravity, whereby lower components are below upper components in the height direction H. If the stationary inductive charging apparatus 1 is arranged on the ground or dug into or buried in the ground, the longitudinal direction L and the lateral direction Q extend horizontally, whereas the height direction H extends vertically.

[0055] In the case of the stationary inductive charging device 1, the coil 2 extends in a transverse plane extending perpendicularly to the height direction H, which can extend parallel to a base plane extending from the longitudinal direction L and the transverse direction Q. The coil 2 is formed with electrical conductor paths configured as strands 3. The inductive charging device 1 further comprises a coil support structure 4 made of plastic in which the strands 3 are at least partially embedded and which serves to position the strands 3. Furthermore, the inductive charging device 1 according to Figs. 1 to 9 comprises a support structure 5 with a number of support elements 6 each extending along the height direction H. Along the longitudinal direction L, the support elements 6 are arranged at a distance from one another. The support elements 6 are supported in the height direction H on the coil support structure 4. Furthermore, the inductive charging device 1 comprises a number of core plates 7 made of soft magnetic material each extending along the longitudinal direction L, which are arranged next to one another at a distance from one another along the longitudinal direction L.

[0056] The inductive charging device 1 has in all illustrated examples a housing 21 which encloses a housing interior space 22. In the exemplary scenario, the housing 21 has upper and lower housing parts 21a, 21b which are opposite each other in the height direction H. In the illustrated example, the upper housing part 21a is part of a housing pot 23 of the housing 21 which opens downwards in the height direction H. The lower housing part 21b is formed as a housing cover 24 for closing the housing pot 23. This housing cover 24 may also be formed by the bottom plate 11 of the inductive charging device 1, which defines the inductive charging device 1 downwards in the height direction H. The coil support structure 4, the core plate 7 and the support structure 5 are arranged in the housing interior space 22 in all examples. The support structure 5 is here supported on the housing cover 24, whereas the coil support structure 4 is supported on the housing pot 23 opposite the housing cover 24. Between the coil support structure 4 and the support structure 5 having the support elements 6, an adapter plate 32 may be arranged in the height direction H, the upper surface 33 of which is placed planarly on the lower surface 36 of the coil support structure 4.

[0057] In an exemplary scenario, the core plates 7 each have a rectangular parallelepiped geometric shaping. Thus, in the vertical cross-sections shown in Figs. 1 to 9, a rectangular geometry results. Each of the core plates 7 has two end faces 12a, 12b extending perpendicularly to the height direction H and four peripheral faces 12c, 12d, 12e, 12f interconnecting these two end faces 12a, 12b. At least one of said faces 12a to 12f has an unpolished surface zone. This means that this unpolished surface zone has not been surface-treated by a polishing process, in particular a polishing process using fine polishing. Preferably, at least one surface zone forms an area proportion of more than 60%, particularly preferably more than 80%, of the respective face 12a to 12f, i.e. of one of the four peripheral faces 12a to 12d or of one of the two end faces 12a to 12f.

[0058] Arranged in the housing pot 23 for each support element 6 is a pressure element 25 which protrudes into the housing interior space 22 and applies pressure to the coil carrier structure 4 and the core plate 7 against the support element 6 of the support structure 5, thereby improving the mechanical stability of the assembly. Expediently, in the height direction H, one pressure element 25 and one support element 6 face each other, so that one core plate 7 and one coil carrier structure 4 are sandwiched between the coil carrier structure 4 and the support structure 5.

[0059] In the example of Fig. 1, each core plate 7 is arranged in an interstitial space 34 formed between two adjacent support elements 6 in the longitudinal direction L. Each of the core plates 7 is supported by two adjacent support elements 5 which define a respective interstitial space 34.

[0060] According to FIG. 1, two adjacent support elements 6 in the longitudinal direction L of the respective core plate 7 can each be formed with a step 10, which step 10 forms a rest surface 8 on which the respective core plate 7 can rest for support in the height direction H. Furthermore, the core plates 7 can be arranged at a distance from the adjacent support elements 6 in the longitudinal direction L, forming respective gaps 9. Particularly preferably, the core plates 7 can be rested on the rest surface 8 of the respective support element 6 along the height direction H. Each core plate 7 is materially connected to the assigned support element 6 by means of three adhesive bonds (not shown). In various variants, a different number of adhesive bonds is also conceivable. Preferably, each adhesive bond has an extension in the longitudinal direction L of between 2 mm and 200 mm.

[0061] FIG. 2 shows the end face 12a of one of the core plates 7 facing the support element 6 opposite the coil support structure 4 in a plan view along the height direction H (with the housing cover 24 removed). This end face 12a of the core plate 7 is thus formed with a positioning contour 13 with a positioning element 14 in each case. Said positioning element 14 can be formed by milled recesses 15 in the end face 12a. Expediently, these recesses 15 are arranged in an outer edge section 16 of each end face 12a, as shown in FIG. 2. In particular, the recesses 15 can be formed so as to open towards an edge 17 of the core plate 7 that defines the outer side of the edge section 16 (this is shown for the two left positioning elements 14 in FIG. 2). For each positioning element 14, an opposite positioning element (not shown) formed complementary to the positioning element 14 can be formed on the rest surface 8 for the lateral positioning of the core plate 7 relative to the support structure 5. In the plan view shown, the positioning elements 14 or the recesses 15 can have essentially any geometric shape. As shown, polygonal, in particular triangular or round, in particular circular, geometries are conceivable. Arc-shaped geometries are also conceivable.

[0062] 3 shows a variant of the example of FIG. 1. Each of the core plates 7 is supported here, for example in contrast to FIG. 1, on exactly one support element 6 and rests on the upper surface 18 of the support element 6 facing the coil support structure 4. Expediently, therefore, exactly one support element 6 is assigned to each core plate 7, which is centrally positioned with respect to the respective core plate 7, as shown. This results in a particularly efficient stress transfer. On the lower end surface 12a of the core plates 7 facing the upper surface 18 of the support element 6, a lower recess 29a is formed in each case, for example by means of milling, in which the support element 6 is partially received, so that the recess bottom surface 19 of the lower recess 29a rests on the upper surface 18 of the support element 6.

[0063] In FIG. 10, a representation is shown which clarifies the lateral arrangement of the lower recesses 29a on the cover surface 12a of the core plate 7 and the relative position of the assigned pressure elements 25. The lower recesses 29a may therefore be arranged as shown in a centered manner on the end surface 12a, where "centering" can refer to the surface center of gravity or the weight center of gravity of the core plate 7. The assigned pressure elements 25 are spaced apart from the core plate 7 in the height direction H as shown in FIG. 3, but are always arranged in the lower recesses 29a with respect to a plane perpendicular to the height direction H, so that the stresses applied by the pressure elements 25 can be absorbed by the support elements 6 arranged inside the lower recesses 29a in any case via the core plate 7. Each support element 6 is thus followed by a pressure element 25 along the height direction H with respect to the respective core plate 7.

[0064] Figures 4 to 9 show a development of the example of Figure 3, for which purpose respective detailed views of the inductive charging device 1 in the area of ​​one of the support elements 6 of the support structure 5 are shown.

[0065] According to a development of Fig. 4, the end face 12b of the core plate 7 facing the coil support structure 4 can also have an upper recess 29b produced by milling in each case, into which a complementarily formed lower projection 45a engages, which projects from the adapter plate 32 in a direction opposite to the height direction H. The adapter plate 32 of the inductive charging device 1 can be provided with such a projection 45a for each core plate 7. By means of the upper recess 29b and the projection 45a, the core plate 7 can be precisely oriented laterally relative to the coil support structure 4, which optimizes the magnetic field guidance.

[0066] Advantageously, the recesses 29a, 29b in the end face 12a or 12b face each other, as shown in Fig. 4, i.e. the lower recess 29a in the end face 12a is continued in an imaginary extension opposite to the height direction H into the upper recess 29a in the end face 12b. Correspondingly, in the example of Fig. 4, each pressure element 25 is continued in the direction opposite to the height direction H by a lower projection 45a, which is continued in the height direction H by a support element 6.

[0067] In the development of FIG. 5, an upper recess 29b produced by milling can also be formed in each case on the end face 12b of the core plate 7 facing the coil support structure 4. In the example of FIG. 5, however, the adapter plate 32 is omitted. In this upper recess 29b, a complementary lower projection 45a thus engages, similar to the example of FIG. 4, but which, in contrast to the example of FIG. 4, does not project from the adapter plate 32 but from the coil support structure 4 in the direction opposite to the height direction H. The coil support structure 4 can be provided with such a lower projection 45a for each core plate 7.

[0068] In the example of FIG. 5, an upper projection 45b projects from the coil support structure 4 on the upper surface 46b of the coil support structure 4 facing away from the core plate 7, which upper projection 45b is supported by a pressure element 25 formed in the upper housing part 21a of the housing 21 and projecting from the housing 21. That is, as shown, the coil support structure 4 is also provided with an upper projection 45b facing in the height direction H for each lower projection 45a. Expediently, also in this development, the projections 45a, 45b on the end face 12a or 12b face each other, i.e. the recess 29a on the lower end face 12a is continued along the height direction H in an imaginary extension of the recess on the upper end face 12b. Correspondingly, in the example of FIG. 5, each pressure element 25 is followed along the height direction H by an upper projection 45b, and each lower projection 45a is followed along the height direction H by a support element 6. The variant of FIG. 5 is therefore simpler to construct and therefore cheaper to manufacture than the variant of FIG. 4 due to the absence of the adapter plate 32 .

[0069] In Fig. 6, a further variant of the example of Fig. 3 is shown. In the example of Fig. 6, a lower or upper protrusion 30a, 30b protrudes from the two end faces 12a, 12b of the core plate 7 in the height direction H and in the direction opposite to the height direction H, respectively, with the aid of which the respective core plate 7 is supported on the coil support structure 4 or on the support element 6 of the support structure 5. Similarly, in the example of Fig. 6, a manner similar to that of Fig. 5, in which an upper protrusion 45b protrudes from the coil support structure 4 on the upper face 46b of the coil support structure 4 facing away from the core plate 7 for each pressure element 25 and each support element 6, which is supported on a pressure element 25 formed on the housing 21 and protruding from the housing 21, is shown. As shown, each upper protrusion 30b faces a lower protrusion 30a along the height direction H.

[0070] 7 shows a further development of the example according to FIG. 3. In this development, a positioning body 26 made of plastic is applied or can be glued to the end face 12a of the core plate 7 facing the support structure 5, which positioning body 26 engages in a recess 28 arranged on the upper face 18 of the respective support element 6 without contacting the support element 6 in the height direction H. This supports a correct lateral positioning of the core plate 7 relative to the support element 6 and thus relative to the other components of the inductive charging device 1. Since the positioning body 26 is spaced apart from the respective support element 6 in the height direction H, the mechanical load path occurs exclusively at the direct contact surface between the core plate 7 and the support element 6, and it is ensured that the positioning body 26 or the positioning element remains load-free after assembly of the inductive charging device 1.

[0071] Figure 8 shows a further development which can be combined as far as it is meaningful with each of the variants according to figures 3 to 7. Here, a thermal filler material 40 is arranged on the upper side 46b of the coil support structure 4 facing away from the core plate 7. As is also shown, a thermal filler material 41 can be arranged on the lower side 46a of the coil support structure 4 facing away from the coil support structure 4, which thermal filler material 41 is supported on the upper side of the core plate 7. This means that the filler material 41 is arranged in a sandwich-like manner between the core plate 7 and the coil support structure 4.

[0072] Figure 9 shows a development of the example of Figures 7 and 8. In the example of Figure 9, the thermal filler material 41 is arranged, in contrast to the variant of Figure 8, additionally on at least one of the peripheral faces 12c-12f, preferably also on the two lower end faces 12a.

[0073] 8 and 9, the filler material 41 may be provided in a notch 47 formed in the lower surface 46a of the coil support structure 4, and the filler material 41 and each of the core plates 7 (on their upper end surfaces 12b, respectively) may be formed in the notch 47. That is, each of the core plates 7 may be provided with such a notch 47.

Claims

1. An inductive charging device (1) for an inductive vehicle charging system for charging the batteries of a battery-electric vehicle, particularly a stationary or mobile inductive charging device, At least one coil (2) for generating an alternating electromagnetic field, formed using an electrical conductor path configured as a strand (3), A coil support structure (4) made of plastic for positioning the wires (3), in which the wires (3) are embedded at least partially, The inductive charging device (1) is positioned below the coil (2) with respect to the height direction (H), and has a plurality of support elements (6) each extending along the height direction (H), which are spaced apart from each other in the longitudinal direction (L) perpendicular to the height direction (H), and a support structure (5) which is supported by the coil support structure (4) in the height direction (H), The device comprises at least two, preferably a plurality of, magnetically conductive core plates (7) made of a soft magnetic material for magnetic flux guidance, each spaced apart from one another along the longitudinal direction (L), each extending along the longitudinal direction (L), and having at least one unpolished surface section, Here, the inductive charging device (1) is such that the at least two core plates (7) are each supported by at least one support element (6) in the height direction (H).

2. At least two of the core plates (7), preferably a plurality of the core plates (7), and particularly preferably all of the core plates (7), each have a single rectangular parallelepiped geometric shape and each has two end faces (12a, 12b) extending perpendicular to the height direction (H) and four circumferential faces (12c, 12d, 12e, 12f). Here, at least one of the surfaces (12a to 12f) has at least one unpolished surface zone, Herein, preferably, the at least one surface zone includes an area ratio of more than 60%, particularly preferably more than 80%, of the respective surfaces (12a to 12f), as described in claim 1, the inductive charging device (1).

3. The induction charging device (1) according to claim 1 or 2, wherein the at least one surface having at least one unpolished surface zone is one of the four circumferential surfaces (12c to 12f), preferably all of the four circumferential surfaces (12c to 12f).

4. The induction charging device (1) according to claim 1 or 2, wherein the at least one surface having the at least one unpolished surface zone is one of the two end faces (12a, 12b), preferably the two end faces (12a, 12b).

5. The induction charging device (1) according to claim 1 or 2, wherein at least one of the aforementioned surfaces (12a to 12f) has two or more unpolished surface zones spaced apart from each other.

6. The inductive charging device (1) includes a housing (21) that surrounds an internal housing space (22) and has upper and lower housing portions (21a, 21b) that face each other in the height direction (H), wherein preferably the upper housing portion (21a) is at least a part of a housing pot (23) that opens to the lower part of the housing (21), and wherein the lower housing portion (21b) forms a housing cover (24) for closing the housing pot (23). The inductive charging device according to claim 1 or 2, wherein the coil support structure (4), the core plate (7), and the support structure (5) are arranged within the internal space (22) of the housing, the support structure (5) is supported by the lower housing portion (21b) or the housing cover (24), and the coil support structure (4) is supported by the upper housing portion (21a).

7. The induction charging device according to claim 6, wherein each support element (6) has a single retaining element (25) positioned in the upper housing portion (21a), particularly the housing pot (23), which protrudes into the internal space (22) of the housing, and the retaining element (25) applies pressure to the support elements (6) of the support structure (5) by pressing the coil support structure (4) and the core plate (7).

8. In the height direction (H), one pressing element (25) and one support element (6) are opposite each other, and thereafter, one core plate (7) and the coil support structure (4) are arranged between the coil support structure (4) and the support structure (5), as described in claim 1 or 2.

9. The inductive charging device according to claim 1 or 2, wherein the coil support structure (4) is arranged in a sandwich-like manner between the support structure (5) and the upper housing portion (21a), or between the conductor plate (7) and the upper housing portion (21a).

10. A stationary inductive charging device according to claim 1 or 2, wherein at least one core plate (7), preferably all core plates (7), are supported by two adjacent support elements (6) in the longitudinal direction (L).

11. The induction charging device according to claim 10, wherein the at least one core plate is spaced apart from the adjacent support elements (6) while forming gaps (9) between them in the longitudinal direction (L).

12. The induction charging device according to claim 10, wherein at least one pressing element (25) faces a support element (6) along the height direction (H), and thereby the coil support structure (4) is sandwiched between the pressing element (25) and the support element (6).

13. The induction charging device according to claim 1 or 2, wherein each of the adjacent support elements (6) has a stepped portion (10) formed thereon, which forms a mounting surface (8) on which the respective core plate (7) is placed for support in the height direction (H).

14. The induction charging device according to claim 13, wherein each of the core plates (7) is placed on the aforementioned mounting surface (8) of each of the support elements (6) in the height direction (H).

15. Each of the core plates (7) is connected to each of the support elements (6) by material bonding using at least two, preferably at least three, and particularly preferably exactly three adhesive bonding portions, each preferably having an extension portion between 2 mm and 200 mm in the longitudinal direction (L). The induction charging device according to claim 1 or 2.

16. A positioning contour (13) having at least one positioning element (14) is formed on the end face (12a) of at least one core plate (7) opposite to the coil support structure (4). The induction charging device according to claim 1 or 2, wherein, for each positioning element (14), an opposing positioning element (15) is formed on one of the plurality of mounting surfaces (8) in a manner complementary to the positioning element (14), for the lateral positioning of the core plate (7) relative to the support structure (5).

17. At least one positioning element (14) is formed by a preferably milled recess (15) provided on the end face (12a), Preferably, at least one recess (15) is located in the outer edge portion (16) of each end face (12a), Particularly preferable is the induction charging device according to claim 16, wherein at least one recess (15) opens toward an edge (17) that defines the outer edge portion (16) of the core plate (7).

18. The inductive charging device according to claim 1 or 2, wherein at least one core plate (7), preferably all core plates (7) are each supported by exactly one support element (6), and preferably rest on the upper surface (18) of the support element (6) facing the coil support structure (4).

19. An inductive charging device according to claim 18, wherein at least one core plate (7), preferably all core plates (7), has a lower recess (29a) formed on its end face (12a) facing the upper surface (18) of the support element (6), preferably by milling, and the support element (6) is partially housed in the lower recess (29a), thereby the bottom surface (19) of the recess (29a) resting on the upper surface (18) of the support element (6).

20. An inductive charging device according to claim 18, wherein a positioning body (26), preferably made of plastic, is attached to the end face (12a) of at least one core plate (7) facing the support structure (5), and is particularly bonded, and the positioning body (26) engages with notches (28) located on the upper surface (18) of each of the support elements (6) without contacting the support elements in the height direction (H).

21. The induction charging device (1) according to claim 1 or 2, wherein the support element (6) extends along the longitudinal direction (L) and is positioned on a bottom plate (11) located below the support structure (6) with respect to the height direction (H).

22. With respect to the height direction (H), an adapter plate (32) is arranged between the coil support structure (4) and the support structure (5), the adapter plate having an upper surface (33) that is placed on the coil support structure (4) in a planar manner, as described in claim 1 or 2.

23. The inductive charging device according to claim 1 or 2, wherein an upper recess (29b) is formed on the end face (12b) of at least one core plate (7) facing the coil support structure (4), and a lower projection (45a) protruding from the coil support structure (4) or the adapter plate (32) preferably engages in a shape-connective manner with the core plate (7).

24. From the upper surface (46b) of the coil support structure (4) opposite to the core plate (7), at least one upper projection (45b) supported by a retaining element (25) formed in the housing protrudes, Preferably, the inductive charging device (1) according to claim 1 or 2, wherein at least one upper projection (45b) and a lower projection (45a) of the coil support structure face each other in the height direction (H).

25. From the end face (12a) of at least one core plate (7) opposite to the coil support structure (4), a downward projection (30a) protrudes in the height direction (H) to support the core plate (7) to the support element (6) of the adjacent support structure (5) in the height direction (H), and / or An inductive charging device (1) according to claim 1 or 2, wherein an upper projection (30b) protrudes in the height direction (H) from the end face (12b) of at least one core plate (7) facing the coil support structure (4), the projection supporting the core plate (7) to the coil support structure (4).

26. Preferably, a thermal filling material (41) is disposed on the cover surface (12b) of the at least one core plate (7) facing the coil support structure (4), and / or An inductive charging device according to claim 1 or 2, wherein a thermal filling material (41) is disposed on the cover surface (12a) of the at least one core plate (7) opposite to the coil support structure (4).

27. The induction charging device according to claim 1 or 2, wherein a thermal filling material (41) is disposed on at least one, preferably all, of the four circumferential surfaces (12c to 12f) of the at least one core plate (7).

28. An inductive vehicle charging system for charging the battery of a battery-electric vehicle, A stationary induction charging device (1) placed on the ground, A mobile inductive charging device (1) located inside or on the vehicle is provided. An inductive vehicle charging system wherein the stationary inductive charging device and / or the mobile inductive charging device is the inductive charging device (1) according to claim 1 or 2.

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