PTC heating module and method for manufacturing the same

Abstract

The present invention relates to a PTC heating module for heating a fluid, a plurality of PTC thermistors, the PTC thermistors having two main surfaces positioned opposite to each other and spaced apart from each other in the thickness direction. The PTC heating module further comprises two contact plates, each having a contact surface, between which the PTC thermistors are arranged adjacent to each other and spaced apart from each other in the thickness direction. The main surfaces of the PTC thermistors are in electrical contact with the contact surfaces of the two contact plates. According to the present invention, the PTC heating module comprises at least one dielectric functional element, which is arranged between the two contact plates and laterally sealed around the PTC thermistor. Therefore, the hollow space between the two contact plates is at least partially filled with the functional element in the thickness direction, and the creepage distance between the two contact plates in the hollow space is enlarged. The present invention also relates to a method for manufacturing a PTC heating module.

Description

Technical Field

[0001] The present invention relates to a PTC heating module for heating a fluid and a method for manufacturing the PTC heating module. The present invention also relates to a method for manufacturing the PTC heating module. Background Art

[0002] A PTC heater (PTC: positive temperature coefficient) generally comprises a plurality of PTC heating modules and is provided for heating a fluid. In a PTC heating module, a plurality of PTC thermistors are composed of a PTC thermistor material mounted between two contact plates, so that when a voltage is applied, the PTC thermistor generates heat, thereby heating a fluid (air or coolant). Such a PTC heater is known, for example, from DE102016107032A1. A PTC heater can be used in an electric vehicle to heat the interior air. In this application, the PTC heating module does not operate with a 12V on-board electrical system voltage, but with a battery voltage of 400V or even 800V in the future. This requires strong electrical insulation to ensure the functionality of the PTC heating module and avoid short circuits on the one hand, and to ensure complete protection of the occupants on the other hand. For this purpose, the fluid side surfaces of all components of the PTC heating module provided with an electric potential must have a minimum distance from other conductive components. These are referred to as air gaps and creepage distances. The air gap provides the shortest distance between two conductive components through the air, while the creepage distance is the distance between two conductive components along the insulating surface. The air gap and creepage distance depend on the maximum test operating voltage. The test voltage can be up to 6kV, so the creepage distance must be up to 4mm and significantly exceeds the layer thickness of conventional PTC thermistors. In addition, the insulation also requires multiple layers that can prevent the heat generated in the PTC thermistor from being dissipated outwards. Summary of the invention

[0003] Therefore, the object of the present invention is to state an improved embodiment or at least an alternative embodiment of a PTC heating module of the generic type for overcoming said disadvantages. The object of the present invention is also to provide a method for manufacturing said PTC heating module.

[0004] A PTC heating module for heating a fluid comprises a plurality of PTC thermistors having two main surfaces, wherein the main surfaces of the respective PTC thermistors are positioned opposite to each other and are spaced apart from each other in the thickness direction. In addition, the PTC heating module comprises two contact plates, each of which has a contact surface, between which the respective PTC thermistors are arranged adjacent to each other transversely to the thickness direction and are spaced apart from each other. The main surfaces of the respective PTC thermistors are in electrical contact with the contact surfaces of the two contact plates. According to the present invention, the PTC heating module comprises at least one dielectric functional element, which is arranged between the two contact plates and is laterally sealed and joined around the respective PTC thermistors. In this way, the hollow space between the two contact plates in the thickness direction is at least partially filled with functional elements, and the creepage distance between the two contact plates is enlarged in the hollow space.

[0005] The functional element partially fills the hollow space of the PTC heating module in the thickness direction, thereby achieving physical separation of the two potential-carrying contact plates. As a result, the creepage distance between the two contact plates is increased and creepage currents are excluded. Here, the functional element is laterally sealed around the PTC thermistor in the PTC heating module so that no creepage current can flow through the lateral air gap between the functional element and the corresponding PTC thermistor. In this way, the electrical contact between the two contact plates in the PTC heating module is achieved only by the PTC thermistor. Through comprehensive electrical insulation within this PTC heating module, the voltage in the PTC heating module can be increased and thus its output can be increased without adjusting the thermistor size in the thickness direction.

[0006] The PTC thermistor can be in electrical contact with the contact plate directly or indirectly. Therefore, the corresponding PTC thermistor can be in electrical contact with the corresponding contact plate, for example, via a conductive layer (for example, made of silver). Alternatively, the conductive contact base can be arranged between the corresponding PTC thermistor and at least one of the two contact plates. The supporting surface of the contact base against the PTC thermistor is smaller than the main surface of the PTC thermistor, so the PTC thermistor protrudes from the contact base transversely to the thickness direction. Here, the contact base can be in electrical contact with the corresponding contact plate and the corresponding PTC thermistor indirectly or directly. Therefore, the conductive layer (for example, composed of silver) can each be arranged, for example, between the contact base and the contact plate and / or the corresponding PTC thermistor. Then, the conductive layer will not protrude or only protrude slightly at the contact base, thereby not shortening the creepage distance between the conductive layer and the contact plate.

[0007] The PTC heating module may include a housing in which a contact plate and a PTC thermistor are fixed. On the end face opposite to the contact surface, the contact plate may be connected to the wall of the housing in a heat transfer manner so that the heat generated in the PTC thermistor can be dissipated to the housing. The housing may be formed of a heat-conducting material (e.g., metal) and then dissipate the heat to a fluid (e.g., air) circulating around the housing. In order to enhance heat dissipation, a slit structure through which the fluid can flow may be fixed or integrally formed on the outside of the housing. In order to electrically insulate the contact plate outwardly and toward the housing of the PTC heating module, a dielectric-based coating may be reliably fixed to the end face of the corresponding contact plate opposite to the contact surface. As an alternative to the dielectric-based coating, the corresponding PTC heating module may include a dielectric insulating cladding. Then, the dielectric insulating cladding covers two contact plates on four sides to electrically insulate these contact plates from the outside. The base coating and the insulating cladding may be heat-conductive so that the heat generated in the corresponding PTC thermistor can be conducted from the corresponding contact plate to the outside of the housing.

[0008] For an advantageous further development of the PTC heating module, it is defined that the dielectric functional element is an insulating plate. The insulating plate is preferably made of ceramic. The insulating plate can, for example, be sandwiched between two contact plates so that the hollow space between the contact plates around the corresponding PTC thermistor is completely filled. Alternatively, the insulating plate can only partially fill the hollow space in the thickness direction and, for example, rest on one of the contact surfaces or be fixed to one of the contact surfaces. It can also be defined that the insulating plate protrudes outward from the hollow space transversely to the thickness direction. In this way, the air gap between the two contact plates is enlarged in the edge region of the contact plates.

[0009] An advantageous alternative to the PTC heating module is that at least one dielectric functional element is defined as a dielectric coating which is firmly bonded to the contact surface of at least one contact plate surrounding the corresponding PTC thermistor. The dielectric coating then completely surrounds the corresponding PTC thermistor in electrical contact with the contact plate and covers the contact surface of the corresponding contact plate. Here, the coating laterally seals adjacent to the corresponding thermistor so that no creepage current can flow through the lateral air gap between the dielectric coating and the corresponding PTC heating module. Here, the dielectric coating can be applied to the corresponding contact surface of the contact plate by injection or by overmolding or by spraying a dielectric material or by anodizing with a dielectric material or by immersion in a dielectric material or by bonding a film consisting of a dielectric material or by other suitable methods. Obviously, the coating method should be selected according to the desired embodiment of the dielectric coating. The dielectric material is preferably a plastic.

[0010] Advantageously, the dielectric coating can be defined to be fixed on the contact surfaces of the two contact plates around the PTC thermistor. The hollow space between the two contact plates can be partially filled in the thickness direction. The dielectric coating then comprises two dielectric discontinuous material partial layers, each of which is fixed to the contact surface of the respective contact plate. In the PTC heating module, the two dielectric material partial layers are separated from each other by an air gap in the thickness direction. The respective dielectric material partial layers engage the respective PTC thermistor in a transverse sealing manner on the contact surface.

[0011] Alternatively, the dielectric coating can be fixed around the PTC thermistor on the contact surfaces of the two contact plates, wherein the hollow space between the two contact plates is completely filled in the thickness direction. The dielectric coating is then formed by a single dielectric material layer, which is located on the contact surface of one contact plate and on the contact surface of the other contact plate in a firmly bonded manner. When manufacturing the PTC heating module, the dielectric material layer can be made of two material part layers on the corresponding contact surfaces which are subsequently connected or pressed to form a single material layer.

[0012] Alternatively, it is possible to define that the dielectric coating on the contact surface of the two contact plates is fixed around the PTC thermistor. Here, the hollow space between the two contact plates can be partially filled in the thickness direction, and the corresponding PTC thermistor is coated transversely to the thickness direction by the dielectric coating. Then, the dielectric coating is formed by a single continuous material layer, which completely separates the PTC thermistor in the hollow space transverse to the thickness direction and the contact surface surrounding the corresponding PTC thermistor from the air. Then, the hollow space remains partially filled in the thickness direction, so that an air gap extending transversely to the thickness direction is retained between the contact plates or in the continuous material layer.

[0013] When a contact base as described above is arranged between the respective PTC thermistor and the respective contact plate, the thickness of at least one contact base defined in the thickness direction may be smaller than the layer thickness of the dielectric coating defined in the thickness direction on the respective contact plate. As a result, the respective contact base is completely coated with the dielectric coating on the respective contact plate transversely to the thickness direction, thereby preventing creepage currents between the contact base and the oppositely positioned contact plate.

[0014] Advantageously, it can be defined that the dielectric coating on the respective contact plate is fixed at least in a plurality of regions outside the respective contact surface and laterally covers the respective contact plate. In this way, the air gap between the two contact plates is enlarged in the edge region of the contact plates. Alternatively or additionally, the dielectric coating can protrude outwards from the hollow space transversely to the thickness direction, so that in the edge region of the contact plates, the air gap between the two contact plates is enlarged. Here, the respective contact plate can also remain laterally uncoated.

[0015] For a further development of the PTC heating module with a dielectric coating, it is defined that the dielectric coating completely covers the corresponding contact plate around the corresponding PTC thermistor and electrically insulates the two contact plates from the outside. In this way, the corresponding contact plate in the PTC heating module can also be electrically insulated relative to the housing of the PTC heating module. The dielectric coating can replace or supplement the above-mentioned dielectric-based coating or the dielectric insulating cladding in the above-mentioned PTC heating module.

[0016] In conclusion, the voltage in the PTC heating module and its output can be increased by the dielectric functional element without adjusting the thermistor size in the thickness direction.

[0017] The invention also relates to a method for producing a PTC heating module as described above. In this case, the respective PTC thermistor is connected to both contact plates simultaneously, or first to one contact plate and then to the other contact plate, and thereby is electrically contacted indirectly or directly with the respective contact plates. Furthermore, before or after the respective PTC thermistor is connected to the respective contact plate, at least one dielectric functional element in the form of a dielectric coating is applied to the contact surface of at least one contact plate.

[0018] In order to electrically insulate the contact plates from the outside, a dielectric-based coating can be applied to the end face of the respective contact plates opposite the contact surface. Alternatively, a dielectric insulating coating can be applied to both contact plates, covering them on four sides. Alternatively or additionally, the dielectric coating on the respective contact plates can be applied in the area outside the respective contact surface, and the respective contact plates can be covered laterally or completely. When the contact plates are covered laterally by the dielectric coating, the air gap in the edge area of ​​the contact plates can be enlarged thereby. When the contact plates are covered completely around the dielectric coating of the respective PTC thermistor, the above-mentioned dielectric-based coating and the above-mentioned insulating coating can be completely replaced or supplemented thereby.

[0019] Advantageously, it can be defined that the dielectric coating is made by injection or by overmolding or by spraying dielectric material or by anodizing with dielectric material or by immersing in dielectric material after the corresponding PTC thermistor is connected to the two contact plates. Alternatively, the dielectric coating can be applied by overmolding or by spraying dielectric material or by anodizing with dielectric material or by immersing in dielectric material or by bonding a film consisting of dielectric material around the PTC thermistor after the corresponding PTC thermistor is connected to the two contact plates. Alternatively, the dielectric coating can be applied around the placeholder element by overmolding or by spraying dielectric material or by anodizing with dielectric material or by immersing in dielectric material or by bonding a film consisting of dielectric material before the corresponding PTC thermistor is connected to the two contact plates. The placeholder element is then removed, and the corresponding PTC thermistor is subsequently connected to the corresponding contact plate at the position maintained by the placeholder element.

[0020] Through the above-mentioned alternatives, multiple possibilities for implementing the method are obtained. Therefore, the PTC thermistor can be first fixed to a contact plate, for example. Thereafter, the dielectric coating can be performed on a contact plate surrounding the PTC thermistor and on another contact plate surrounding the placeholder element. Once the placeholder element is removed, the PTC thermistor can be connected to another contact plate at the maintained position, thereby manufacturing a PTC heating module. Alternatively, the dielectric coating can be applied to the two contact plates surrounding the placeholder element. Once the placeholder element is removed, the PTC thermistor can be connected to the contact plates. This can be done simultaneously with the two contact plates, or first with one contact plate and then with the other contact plate. Alternatively, the two contact plates can be connected to the PTC thermistor and then the dielectric coating is applied. Basically, the execution of the method can be matched with the configuration of the desired dielectric coating.

[0021] It is understood that the features mentioned above and the features yet to be explained below can be used not only in the respective combination stated but also in other combinations or alone without departing from the scope of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Preferred exemplary embodiments of the invention are shown in the drawings and are explained in more detail in the following description, wherein the same reference numerals relate to the same or similar or functionally identical components.

[0023] Schematically shown respectively

[0024] Figures 1 to 12 are cross-sectional views of differently configured PTC heating modules according to the present invention. DETAILED DESCRIPTION

[0025] Figure 1A cross-sectional view of a PTC heating module 1 for heating a fluid according to the present invention is shown. The PTC heating module 1 includes a plurality of PTC thermistors 2 and two contact plates 3a and 3b made of a PTC thermistor material, wherein the PTC thermistors 2 are stacked together in a thickness direction 4. The respective PTC thermistors 2 each include two main surfaces 5a and 5b, which are opposite to each other and spaced apart relative to each other in the thickness direction 4. The main surfaces 5a and 5b are directly or indirectly electrically contacted with the contact surfaces 6a and 6b of the respective contact plates 3a and 3b, respectively, so that the respective PTC thermistors 2 are electrically contacted with the contact plates 3a and 3b. The contact plates 3a and 3b can be connected to an external voltage source, for which contact elements 7a and 7b are formed or fixed on the contact plates 3a and 3b. In this exemplary embodiment, the PTC heating module 1 includes a housing 8, which provides a cladding for the two contact plates 3a and 3b and the PTC thermistor 2 arranged therebetween. On the housing 8, a rib structure 9 (shown only schematically here) is fixed, through which a fluid such as air can flow. The respective PTC thermistors 2 are arranged adjacent to each other transversely with respect to the thickness direction 4 and are spaced apart with respect to each other, so that a hollow space 10 is formed between the two contact plates 3a and 3b.

[0026] Furthermore, the PTC heating module 1 comprises a functional element 11, which in this exemplary embodiment is a dielectric coating 12. The dielectric coating 12 is fixed around the PTC thermistor 2 on the contact surfaces 6a and 6b of the contact plates 3a and 3b in a firmly bonded manner and completely fills the hollow space 10. The coating 12 laterally adjoins the thermistor 2 in a sealing manner so that no creepage current flows through the lateral air gap between the dielectric coating 12 and the PTC thermistor 2. The creepage distance between the two contact plates 3a and 3b is enlarged in the hollow space 10. In this exemplary embodiment, the dielectric coating 12 comprises two dielectric material partial layers 13a and 13b, each of which is fixed on the contact surfaces 6a and 6b of the respective contact plates 3a and 3b. In the PTC heating module 1, the two dielectric material partial layers 13a and 13b are arranged opposite to each other in the thickness direction 4 and form a continuous material layer 13, so that the hollow space 10 is completely filled in the thickness direction 4.

[0027] In this exemplary embodiment, the dielectric coating 12 or material layers 13a and 13b completely envelop the corresponding contact plates 3a and 3b around the PTC thermistor 2, so that the contact plates 3a and 3b are simultaneously covered by the dielectric coating 12 laterally and on their end faces 14a and 14b or by the material partial layers 13a and 13b. Therefore, the air gap in the edge region 15 of the corresponding contact plates 3a and 3b is reduced. In addition, the dielectric coating 12 or material partial layers 13a and 13b are applied to the end faces 14a and 14b, and the two contact plates 3a and 3b are electrically insulated from the housing 8 of the PTC heating module 1. Here, the dielectric coating 12 can be thermally conductive, so that the heat generated in the PTC thermistor 2 can be dissipated to the housing 8 via the contact plates 3a and 3b and the dielectric coating 12, and further dissipated to the fluid flowing through the rib structure 9 via the rib structure 9.

[0028] In the following, different configurations of the PTC heating module 1 are explained. For the sake of clarity, the housing 8 and the rib structure 9 are not shown in FIG. Figures 2 to 12 However, these can be Figure 1 The PTC heating module 1 in FIG. 1 is implemented in the same manner. In addition, in some embodiments, no insulation is shown on the end faces 14a and 14b. It goes without saying that such insulation can be achieved by a base coating or an insulating cladding if not provided otherwise.

[0029] Figure 2 A cross-sectional view of an alternatively configured PTC heating module 1 is shown, in which the functional element 11 has the form of a dielectric coating 12. In the PTC heating module 1 shown here, the dielectric coating 12 is formed by a single material layer 17, which can be produced, for example, by injecting a dielectric material, preferably plastic, into the hollow space 10, and in this exemplary embodiment, the dielectric coating 12 or material layer 17 is joined laterally around the respective contact plates 3a and 3b, so that the air gap in the edge region 15 of the contact plates 3a and 3b is enlarged. Here, no dielectric coating 12 is applied to the end faces 14a and 14b.

[0030] Figure 3 FIG. 1 shows a cross-sectional view of an alternatively configured PTC heating module, in which the functional element 11 is in the form of a dielectric coating 12. In this exemplary embodiment, the dielectric coating 12 comprises material partial layers 13a and 13b, which are connected to the dielectric coating 12. Figure 1 In contrast to the embodiment of , this embodiment is not continuous. Therefore, the hollow space 10 is only partially filled in the thickness direction 4. The material partial layers 13a and 13b are joined laterally around the contact plates 3a and 3b, thereby enlarging the air gap in the edge region 15. Here, no dielectric coating 12 is applied to the end faces 14a and 14b.

[0031] Figure 4A cross-sectional view of an alternatively configured PTC heating module 1 is shown, in which the functional element 11 has the form of a dielectric coating 12. In this exemplary embodiment, the dielectric coating 12 is formed by a continuous material layer 17, which separates the PTC thermistor 2 in the hollow space 10 transverse to the thickness direction 4 and the contact surfaces 6a and 6b surrounding the respective PTC thermistor 2 from the air. However, the hollow space 10 is partially filled in the thickness direction 4, so that an air gap extending transverse to the thickness direction 4 is retained between the contact plates 3a and 3b within the continuous material layer 17. Here, the dielectric coating 12 or material layer 17 also surrounds the contact plates 3a and 3b laterally so as to enlarge the air gap in the edge region 15 of the contact plates 3a and 3b. Here, no dielectric coating 12 is applied to the end faces 14a and 14b.

[0032] Figure 5 The embodiment without the housing 8 and without the rib structure 9 is shown. Figure 1 sectional view of a PTC heating module 1.

[0033] Figure 6 1 shows a cross-sectional view of an alternatively configured PTC heating module 1, in which the functional element 11 is in the form of a dielectric coating 12. In this exemplary embodiment, different from Figure 3 , the dielectric coating 12 is also applied to the end faces 14a and 14b of the contact plates 3a and 3b. Here, the base coating and the insulating coating can be omitted. Otherwise, in this case, the PTC heating module 1 corresponds to Figure 3 PTC heating module in.

[0034] Figure 7 A cross-sectional view of an alternatively configured PTC heating module 1 is shown, in which the functional element 11 has the form of an insulating plate 18. The insulating plate 18 is preferably made of ceramic and is arranged between the two contact plates 3a and 3b, so that the hollow space 10 between the contact plates 3a and 3b around the corresponding PTC thermistor 2 is completely filled. In addition, the insulating plate 18 protrudes outwardly from the hollow space 10 transversely to the thickness direction 4, thereby increasing the air gap in the edge region 15 of the contact plates 3a and 3b.

[0035] Figure 8 A cross-sectional view of an alternatively configured PTC heating module 1 is shown, in which the functional element 11 is in the form of a dielectric coating 12. In this exemplary embodiment, the base coating 16 or the insulating coating 20 is applied to the end faces 14a of the contact plates 14b and 14b of the contact plates 3a and 3b. This is not distinguishable in the cross-sectional view shown here. Otherwise, the PTC heating module 1 in this case corresponds to Figure 2 PTC heating module in.

[0036] Fig. 9FIG. 1 shows a cross-sectional view of an alternatively configured PTC heating module 1 , in which the functional element 11 is in the form of a dielectric coating 12 . Figure 3 In this case, the dielectric coating 12 does not engage the contact plates 3a and 3b. Instead, the dielectric coating 12 protrudes from the hollow space 12 transversely to the thickness direction 4, thereby enlarging the air gap in the edge region 15 of the contact plates 3a and 3b. Otherwise, in this case, the PTC heating module 1 corresponds to Figure 3 PTC heating module in.

[0037] Fig.10 FIG. 1 shows a cross-sectional view of an alternatively configured PTC heating module 1 , in which the functional element 11 is in the form of a dielectric coating 12 . Figure 2 , in which case the respective PTC thermistor 2 is electrically contacted with the respective contact plates 3a and 3b via the contact bases 19a and 19b, respectively. The support surfaces 21a and 21b of the respective contact bases 19a and 19b are smaller than the respective main surfaces 5a and 5b of the PTC thermistor 2, so that the respective PTC thermistor 2 protrudes on the respective contact bases 19a and 19b transversely to the thickness. In addition, the thickness of the respective contact bases 19a and 19b is smaller than the layer thickness of the material partial layers 13a and 13b in the thickness direction 4, so that the contact bases 19a and 19b are completely covered by the dielectric coating 12 in the transverse direction.

[0038] Fig.11 FIG. 1 shows a cross-sectional view of an alternatively configured PTC heating module 1 , in which the functional element 11 is in the form of a dielectric coating 12 . Figure 3 In contrast to the embodiment in FIG. 1 , in this case the respective PTC thermistor 2 is in electrical contact with the respective contact plates 3a and 3b via contact bases 19a and 19b. Here, the dielectric coating 12 is formed by two material partial layers 13a and 13b, wherein the respective material partial layers 13a and 13b laterally completely envelop the respective contact bases 19a and 19b. Otherwise, in this case, the PTC module 1 corresponds to Figure 3 PTC heating module in.

[0039] Fig.12 A cross-sectional view of an alternatively configured PTC heating module 1 is shown, in which the functional element 11 is in the form of a dielectric coating 12. Here, too, the corresponding PTC thermistor 2 is in electrical contact with the contact plates 3a and 3b via contact bases 19a and 19b. Otherwise, the PTC heating module 1 in this case corresponds to Figure 2 PTC heating module in.

[0040] The dielectric material may be applied by injection or by coating or by spraying the dielectric material or by anodizing with the dielectric material or by dipping into the dielectric material or by bonding a film of the dielectric material or by other suitable methods. Figures 1 to 6as well as Figures 8 to 12 The dielectric coating 12 in the embodiment of the dielectric coating 12 is applied. It goes without saying that the coating method should be selected according to the desired embodiment of the dielectric coating 12. The dielectric material is preferably a plastic. The base coating and the insulating cladding are formed from an electrically and preferably thermally conductive material. The respective contact plates 3a and 3b as well as the housing 8 and the rib structure 9 can consist of metal, for example. The respective PTC thermistor is made of a PTC thermistor material. Figure 6 The insulating plate 18 in the embodiment may be made of, for example, ceramic.

[0041] In summary, the two potential-carrying contact plates 3a and 3b in the PTC heating module 1 are physically separated from each other by the functional element 11. Therefore, the creepage distance between the two contact plates 3a and 3b is enlarged, and the creepage current in the PTC heating module 1 is excluded. In summary, the voltage in the PTC heating module 1 can be increased and thus its output can be increased without adjusting the size of the PTC thermistor 2 in the thickness direction 4.

Claims

1. A PTC heating module (1) for heating a fluid, The PTC heating module (1) comprises a plurality of PTC thermistors (2) having two main surfaces (5a, 5b), wherein the main surfaces (5a, 5b) of the PTC thermistors (2) are positioned opposite to each other and are spaced apart from each other in a thickness direction (4), The PTC heating module (1) comprises two contact plates (3a, 3b), each of which has a contact surface (6a, 6b), between which the PTC thermistor (2) is arranged transversely to the thickness direction (4), facing each other and spaced apart from each other, wherein the main surface (5a, 5b) of the PTC thermistor (2) is in electrical contact with the contact surfaces (6a, 6b) of the two contact plates (3a, 3b), It is characterized in that The PTC heating module (1) comprises at least one dielectric functional element (11), which is arranged between the two contact plates (3a, 3b) and laterally sealed around the PTC thermistor (2), so that the hollow space (10) between the two contact plates (3a, 3b) in the thickness direction (4) is at least partially filled with the dielectric functional element (11), so as to achieve physical separation of the two contact plates (3a, 3b) and enlarge the creepage distance between the two contact plates (3a, 3b) in the hollow space (10).

2. The PTC heating module according to claim 1, It is characterized in that The dielectric functional element (11) is an insulating plate (18).

3. The PTC heating module according to claim 2, It is characterized in that The insulating plate (18) is made of ceramic.

4. The PTC heating module according to claim 2, It is characterized in that The insulating plate (18) protrudes outward from the hollow space (10) transversely to the thickness direction (4), so that the gap between the two contact plates (3a, 3b) is enlarged in the edge region (15) of the contact plates (3a, 3b).

5. The PTC heating module according to claim 1, It is characterized in that The at least one dielectric functional element (11) is a dielectric coating (12) which is fixed in a firmly bonded manner to a contact surface (6a, 6b) of at least one contact plate (3a, 3b) surrounding the PTC thermistor (2).

6. The PTC heating module according to claim 5, It is characterized in that The dielectric coating (12) is fixed on the contact surfaces (6a, 6b) of the two contact plates (3a, 3b) surrounding the PTC thermistor (2), wherein a hollow space (10) between the two contact plates (3a, 3b) in the thickness direction (4) is partially filled, or The dielectric coating (12) is fixed on the contact surfaces (6a, 6b) of the two contact plates (3a, 3b) surrounding the PTC thermistor (2), wherein the hollow space (10) between the two contact plates (3a, 3b) in the thickness direction (4) is completely filled, or The dielectric coating (12) is fixed on the contact surfaces (6a, 6b) of the two contact plates (3a, 3b) surrounding the PTC thermistor (2), wherein a hollow space (10) between the two contact plates (3a, 3b) in the thickness direction (4) is partially filled, and the PTC thermistor (2) is covered by the dielectric coating (12) transversely to the thickness direction (4).

7. The PTC heating module according to claim 5, It is characterized in that The dielectric coating (12) on the contact plates (3a, 3b) is applied outside the contact surface (6a, 6b) at least in a plurality of regions and laterally covers the contact plates (3a, 3b) so that in the edge region (15) of the contact plates (3a, 3b), the air gap between the two contact plates (3a, 3b) is enlarged, and / or The dielectric coating (12) transversely to the thickness direction (4) protrudes outward from the hollow space (10), so that the air gap between the two contact plates (3a, 3b) is enlarged in the edge region (15) of the contact plates (3a, 3b).

8. The PTC heating module according to any one of claims 5 to 7, It is characterized in that The dielectric coating (12) completely covers the contact plates (3a, 3b) surrounding the PTC thermistor (2), and the two contact plates (3a, 3b) are electrically insulated to the outside.

9. The PTC heating module according to any one of claims 1 to 7, It is characterized in that On the end surface (14a, 14b) opposite to the contact surface (6a, 6b) of the contact surfaces (6a, 6b), a dielectric-based coating (16) is fixed in a firmly bonded manner, said dielectric-based coating electrically insulating the two contact plates (3a, 3b) outwardly, or The PTC heating module (1) has a dielectric insulating sheath (20) which surrounds the two contact plates (3a, 3b) on four sides and electrically insulates them to the outside.

10. The PTC heating module according to any one of claims 5 to 7, It is characterized in that An electrically conductive contact base (19a, 19b) is provided between the PTC thermistor (2) and at least one of the two contact plates (3a, 3b), the support surface (21a, 21b) of which is smaller than the main surface (5a, 5b) of the PTC thermistor (2), and the PTC thermistor (2) protrudes from the contact base (19a, 19b) transversely to the thickness direction (4).

11. The PTC heating module according to claim 10, It is characterized in that The thickness defined in the thickness direction (4) of the at least one contact base (19a, 19b) is smaller than the thickness of the dielectric coating (12) defined in the thickness direction (4) on the contact plate (3a, 3b), so that the contact base (19a, 19b) transverse to the thickness direction (4) is completely covered by the dielectric coating (12) on the contact plate (3a, 3b).

12. A method for producing a PTC heating module (1) according to any one of the preceding claims, wherein the PTC thermistor (2) is connected to the two contact plates (3a, 3b) simultaneously or first to one contact plate (3a, 3b) and then to the other contact plate (3a, 3b), thereby indirectly or directly making electrical contact with the contact plates (3a, 3b), and The at least one dielectric functional element (11) in the form of a dielectric coating (12) is applied to a contact surface (6a, 6b) of the at least one contact plate (3a, 3b) before or after the PTC thermistor (2) is connected to the contact plate (3a, 3b).

13. The method according to claim 12, It is characterized in that The dielectric coating (12) on the contact plates (3a, 3b) is coated outside the contact surface (6a, 6b) at least in a plurality of regions and the contact plates (3a, 3b) are laterally or completely covered, or A dielectric-based coating (16) is applied to the end surface (14a, 14b) of the contact plate (3a, 3b) opposite to the contact surface (6a, 6b), or A dielectric insulating coating (20) is arranged on the two contact plates (3a, 3b) and covers them on four sides.

14. A method according to claim 12 or 13, It is characterized in that After the PTC thermistor (2) is connected to the two contact plates (3a, 3b), the dielectric coating (12) is applied by injecting or overmolding or spraying a dielectric material in the hollow space (10), or by dipping into a dielectric material or by anodizing with a dielectric material.

15. The method according to claim 13, It is characterized in that After the PTC thermistor (2) is connected to the contact plate (3a, 3b) surrounding the PTC thermistor (2), the dielectric coating (12) is applied by overmolding or spraying the dielectric material, or by dipping into the dielectric material, or by anodizing with the dielectric material, or by bonding a film of the dielectric material, Before the PTC thermistor (2) is connected to the contact plate (3a, 3b) surrounding the PTC thermistor (2), the dielectric coating (12) is coated by overmolding or spraying a dielectric material, or by anodizing with a dielectric material, or by dipping into a dielectric material, or by bonding a film of a dielectric material, and then the placeholder element is removed, and the PTC thermistor (2) at the position held by the placeholder element is subsequently connected to the contact plate (3a, 3b).

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