Heating module with spring element, water separator, fuel cell and vehicle

Abstract

The invention relates to a heating module (10) comprising a heating assembly (11) and a spring element (12) for transmitting a pressing force (F) to the heating assembly (11), wherein: the spring element (12) comprises at least one spring portion (13); the spring portion (13) has a wave shape, the wave shape comprising at least one wave crest (14) remote from the heating assembly (11) and at least two wave troughs (15) next to the heating assembly (11); and the spring portion (13) is in contact with the heating assembly (11) at least in two contact regions (KB) formed by the wave troughs (15).

Description

[0001] R.414210

[0002] - 1 -

[0003] Description

[0004] title

[0005] Heating module with spring element, water separator, fuel cell and vehicle

[0006] In fuel cell water separators, water can freeze, leading to ice formation. In this case, it is necessary to thaw the ice by applying heat to ensure the continued, trouble-free operation of the fuel cell and / or water separator. Heating modules, particularly electrically operated ones, are used to generate this heat. The heat generated by the heating modules is transferred to the ice via a thermal mass to thaw it. This thermal mass can be, for example, a housing structure or enclosure. Therefore, efficient heat transfer between the heating module and the thermal mass is essential to achieve thawing with minimal energy consumption.

[0007] Disclosure of the invention

[0008] The present invention relates to a heating module, a water separator, a fuel cell, and a vehicle. Further features and details of the invention will become apparent from the dependent claims, the description, and the drawings. Features and details described in connection with the heating module according to the invention naturally also apply in connection with the water separator and / or the fuel cell and / or the vehicle according to the invention, and vice versa, so that the disclosure regarding the individual aspects of the invention always includes or allows for reciprocal reference. R.414210

[0009] - 2 -

[0010] The invention presented here serves in particular to improve the efficiency of heat transfer between a heating module and a thermal mass, especially in a fuel cell.

[0011] According to a first aspect, the present invention relates to a heating module comprising a heating element and a spring element for transmitting a contact force to the heating element. The spring element comprises at least one spring section, wherein the spring section has a wave shape, the wave shape comprising at least one wave crest facing away from the heating element and at least two wave troughs facing the heating element, wherein the spring element, in particular the spring section, is in contact with the heating element at at least two contact areas formed by the wave troughs.

[0012] A heating module according to the invention offers the advantage that a contact force applied to the heating module via the spring element, in particular via at least one spring section of the spring element, is distributed by the wave shape of the spring section across the contact areas formed by the wave troughs. This allows for an advantageous distribution of the contact force across the heating assembly, resulting in improved contact of the heating assembly with a thermal mass and thus more efficient heat transfer between the heating assembly and the thermal mass. Furthermore, by distributing the contact force across the heating assembly, bending moments within the heating assembly can also be avoided or reduced, thereby achieving advantageous mutual contact between the components of the heating assembly with regard to internal heat transfer within the heating assembly.

[0013] The heating module can preferably be intended for use in a fuel cell, in particular in a fuel cell water separator. Additionally or alternatively, the heating module can be intended for use in a vehicle. R.414210

[0014] - 3 -

[0015] A wave crest is to be understood here as a region of a spring section in which, starting from a longitudinal axis of the spring section, the material of the spring section rises in a first direction relative to the longitudinal axis in the direction of a crest of the wave and then descends again in the direction of the longitudinal axis. A wave trough is to be understood here as a region of a spring section in which, starting from the longitudinal axis of the spring section, the material of the spring section descends in a second direction opposite to the first direction relative to the longitudinal axis in the direction of a trough of the wave and then rises again in the direction of the longitudinal axis.

[0016] With regard to the present invention, it is advantageously provided that the spring element comprises a plurality of spring sections arranged adjacent to one another. In particular, at least two or all spring sections can be identical and / or, especially with respect to a respective longitudinal axis or longitudinal extent of the spring sections, be oriented parallel or substantially parallel to one another. By using several spring sections, an improved, and in particular a more uniform, distribution of a contact force applied to the heating module can be achieved through an increased number of contact areas. In particular, the contact force can thus be distributed over several heating elements encompassed by the heating assembly and / or advantageously distributed with respect to a single heating element.When using multiple heating elements, a division into several, especially parallel, spring sections can also be advantageous for compensating for any thickness tolerances of the heating elements and improving the distribution of the contact force between the heating elements and the thermal mass.

[0017] At least one contact area can preferably be configured as a point contact area. Alternatively, and particularly preferably, at least one contact area can be configured as a linear or planar contact area. A linear or planar configuration of a contact area, in particular, results in an advantageous force distribution during force transmission between the spring section and the heating element. R.414210

[0018] - 4 -

[0019] It can be provided that at least two spring sections, in particular all spring sections, are in contact with the heating element at at least two contact areas formed by the wave troughs. Additionally or alternatively, it is conceivable that at least two spring sections, in particular all spring sections, have the same number of wave crests and / or wave troughs. Additionally or alternatively, it is conceivable that the wave troughs and wave crests of at least one spring section are arranged alternately along a longitudinal extent or longitudinal axis of the spring section.

[0020] It is conceivable that at least one spring section comprises at least 3, in particular at least 4, preferably at least 5, and most preferably at least 6 troughs and / or crests. The number of troughs and crests can be selected, in particular, depending on the longitudinal extent of the spring section, along which the troughs and crests are arranged alternately. Thus, for a given longitudinal extent of the spring section, an increasing number of troughs and crests results in an increasing stiffness of the spring section, which in turn increases the force required to preload the spring element or spring section along a given spring travel. In this context, insufficient spring travel can negatively affect the handling of the heating module during assembly.

[0021] In a preferred embodiment, the spring element comprises four spring sections, wherein the spring sections are identical in design, arranged adjacent to one another, and oriented parallel or substantially parallel, particularly with respect to a longitudinal axis or extent of the spring sections. Such a design has proven to be particularly advantageous with regard to favorable force distribution and cost-effective manufacturing.

[0022] It can be provided that at least two spring sections, and in particular all spring sections, are connected to each other via a fastening section. The fastening section can preferably be, at least partially, R.414210

[0023] - 5 - be connected to the heating system. In particular, it may be provided that the fastening section connects the respective beginnings of the waveform of the spring sections to each other or that the respective beginnings of the waveform of the spring sections adjoin the fastening section.

[0024] Within the scope of the invention, it is preferably provided that the heating assembly comprises at least one heating element, in particular an electrically operated one, wherein the heating element and the spring element are positioned relative to each other such that at least one contact area is arranged in overlap with the heating element. This has the advantage that a contact force introduced into the spring element or spring section is transferred to the heating element. This promotes efficient heat transfer within the heating assembly.

[0025] In this context, it is preferable that the contact area be arranged at a distance from an edge of the heating element. The distance of the contact area from the edge of the heating element can preferably be at least 5%, more preferably at least 10% or at least 20% of the length of the heating element along the longitudinal extent of the spring section. Particularly when using PTC elements as heating elements, it has proven advantageous not to introduce a contact force into the PTC element in the immediate edge region, as this promotes damage to the PTC element and inefficient heat transfer.

[0026] Within the scope of the invention, it is conceivable that in at least one spring section, and in particular in all spring sections, all contact areas formed by the wave troughs are arranged in overlap with the same heating element. In other words, the contact force transmitted via the spring section is completely introduced into the heating system in the area of ​​one heating element. Particularly when several heating elements are arranged adjacent to each other orthogonally to a longitudinal extent of the spring section(s), an advantageous force transmission can thus be achieved even when using multiple heating elements. R.414210

[0027] - 6 -

[0028] Additionally or alternatively, it can be provided that, in at least one spring section, and in particular in all spring sections, all contact areas formed by the wave troughs are arranged in overlap with different heating elements. In other words, the contact force transmitted via the spring section is distributed across the wave troughs to different heating elements. Particularly when several heating elements are arranged adjacent to each other along the longitudinal extent of the spring section(s), an advantageous force transmission can thus be achieved even when using multiple heating elements.

[0029] Advantageously, and in any combination with the described embodiments of the heating module, the heating assembly can include at least one heating element, in particular an electrically operated one. At least one heating element can be designed as a positive temperature coefficient (PTC) element. The PTC element is a ceramic-based thermistor with a positive temperature coefficient, meaning that the PTC element conducts electricity better at low temperatures than at high temperatures. As the temperature increases, the intrinsic resistance of the PTC increases, and its conductivity and power output decrease. This self-regulating property means that PTC elements cannot overheat, or at least not significantly. The use of such heating elements has proven particularly advantageous in relation to the present invention.

[0030] With regard to the invention, it is preferably provided that at least one spring section has at least one wave trough that has a linear profile, at least partially, in a crest of the wave trough. In this way, when the spring section is pre-tensioned, a bulge can be created in the linearly extending area, forming two contact areas within this area. Accordingly, an improved distribution of the contact force can be achieved. Such a design has proven particularly advantageous for wave troughs adjacent to both sides of which a wave crest is arranged. This results in R.414210

[0031] - 7 - an introduction of the contact force via the wave crests on both sides of the wave trough in question, which has proven advantageous for the production of the described curvature in the linear course of the crest of the wave trough.

[0032] A crest is defined here as the region or point in the course of a wave trough or wave crest where the wave crest or trough reaches its highest or lowest point, respectively. If the crest follows a linear path, it forms a plateau. In particular, at least one contact zone formed by a wave crest and / or a wave trough can be located at the respective crest of the wave crest or trough.

[0033] With regard to the present invention, it is conceivable that in at least one spring section, and in particular in all spring sections, a beginning and / or an end of the spring section is located closer to a longitudinal axis of the spring section than at least one crest of a wave crest and / or trough. In other words, it can be provided that in at least one spring section, the beginning and / or end of the spring section are positioned such that they are located below or above a crest of at least one wave crest and / or trough located between the beginning and the end of the spring section. This results in simplified handling of the heating module during assembly and, furthermore, in the application of the contact force exclusively via wave crests spaced apart from the end or beginning of the spring section, which has proven advantageous with regard to a uniform force distribution.

[0034] With regard to the present invention, it is further conceivable that the heating system comprises at least one busbar. It can be provided that at least one busbar, at least partially, is in contact with at least one other busbar via at least one contact surface.

[0035] In particular, it is conceivable that at least two or exactly two busbars are included, with at least one heating element between the busbars R.414210

[0036] - 8 - is arranged and is in contact with the busbars via at least one contact surface. The busbars allow the heating element to be directly supplied with electrical energy, thus generating heat through the heating system. The direct contact of the heating element with the busbars results in efficient heat transfer within the heating system. Preferably, when using only one busbar, the thermal mass can be electrically conductive, and in particular, at least one heating element can be in contact with the thermal mass, at least partially, via at least one contact surface. In this way, the thermal mass itself can function as a busbar or fulfill the function of the second busbar.

[0037] Additionally or alternatively, the heating element can be provided with an insulating sheath for electrically isolating the spring element from the heating element, with the contact areas being formed on the insulating sheath. In particular, the insulating sheath can form an outer surface of the heating element, at least in sections. In other words, the heating element is encased by the insulating sheath, at least in sections, and the spring element, or at least a section of the spring element, rests on the insulating sheath in the contact areas. This allows the spring element and other components adjacent to the heating element, such as a thermal mass, to be electrically decoupled from the heating element. Such a design has proven particularly advantageous when using PTC elements in conjunction with busbars to supply current to the PTC elements.

[0038] It may further be provided that the heating assembly comprises at least one support element, wherein at least one heating element and / or at least one busbar and / or an insulating sheath and / or at least one spring element are arranged on or connected to the support element, at least partially. The support element may preferably be made of plastic. R.414210

[0039] - 9 -

[0040] A preferred embodiment of the invention may consist in the spring element being made, at least partially, and in particular completely, of a stainless steel, especially chromium-nickel steel. This has proven advantageous with regard to the durability of the spring element. Preferably, it may be a cold-rolled spring steel strip, in particular of type 1.4310 or AISI 304.

[0041] According to a second aspect of the invention, the subject matter of the invention is further a water separator, in particular for use in a fuel cell and / or a vehicle. The water separator comprises a thermal mass and at least one heating module according to the invention, in particular at least one heating module according to any one of claims 1 to 11, wherein the heating module is arranged, at least partially, in conjunction with the thermal mass. A water separator according to the invention offers the same advantages as those described with respect to a heating module according to the invention.

[0042] With regard to a water separator, it can be advantageously provided that the heating module is arranged in a receiving pocket formed in the thermal mass, wherein the receiving pocket has an undersize relative to the heating module, such that at least one spring section of the spring element, and in particular all spring sections of the heating module, are pre-tensioned by the arrangement of the heating module in the receiving pocket. Thus, by arranging the heating module in the receiving pocket, a contact force resulting from the undersize can be imposed on the spring element, or at least one spring section of the spring element, and the spring element can be pre-tensioned in this way. This enables a secure and structurally simple fixation of the heating module and simultaneously achieves an advantageous contact of the heating module with the thermal mass with respect to efficient heat transfer.

[0043] In particular, it is conceivable that the heating module is arranged in the receiving pocket such that it is in contact with the thermal mass via at least one contact area formed by a wave crest. The heating module can be connected to the R.414210 at a plurality of contact areas.

[0044] - 10 - thermal mass in contact, wherein the contact areas are formed by wave crests of at least one spring section or several spring sections.

[0045] According to a third aspect of the invention, the subject matter of the invention is further a fuel cell, wherein the fuel cell comprises at least one water separator according to the invention, in particular at least one water separator according to claim 12 or 13, and / or at least one heating module according to the invention, in particular at least one heating module according to any one of claims 1 to 11. A fuel cell according to the invention offers the same advantages as those described with respect to a heating module and / or a water separator according to the invention.

[0046] According to a fourth aspect of the invention, a vehicle is further provided, comprising at least one water separator according to the invention, in particular at least one water separator according to claim 12 or 13, and / or at least one heating module according to the invention, in particular at least one heating module according to any one of claims 1 to 11, and / or at least one fuel cell according to the invention, in particular at least one fuel cell according to claim 14. A vehicle according to the invention offers the same advantages as those described with respect to a heating module and / or a water separator according to the invention. In particular, at least one heating module can be integrated into the vehicle such that the heating module can be used, or is used, to heat a urea solution, preferably a urea solution sold under the trade name "AdBlue".The urea solution can preferably be used for exhaust gas purification in the vehicle. Within the scope of the invention, it has been found that heating modules according to the invention can also be advantageously used for thawing the urea solution at low ambient temperatures. Additionally or alternatively, the vehicle can include at least one fuel cell, in particular one according to the invention, for providing electrical energy for propelling the vehicle. R.414210.

[0047] - 11 -

[0048] The vehicle can preferably be designed as a car, in particular a passenger car, or as a commercial vehicle, in particular a truck.

[0049] Advantages that are described in detail for the heating module according to the first aspect of the invention and for the water separator according to the second aspect of the invention apply equally to the fuel cell according to the third aspect of the invention and to the vehicle according to the fourth aspect of the invention, and vice versa.

[0050] Further advantages, features, and details of the invention will become apparent from the following description, in which exemplary embodiments of the invention are described in detail with reference to the drawings. The features mentioned in the claims and in the description can each be essential to the invention individually or in any combination.

[0051] Each schematically illustrates:

[0052] Figure 1 shows a view of a heating module,

[0053] Figure 2 shows a view of a spring section,

[0054] Figure 3 shows a view of a spring element,

[0055] Figure 4 shows a sectional view of a heating system.

[0056] Figure 5 shows a view of a spring section,

[0057] Figure 6 shows a view of a water separator.

[0058] Figure 7 shows a view of a fuel cell and

[0059] Figure 8 shows a view of a vehicle.

[0060] Fig. 1 shows a schematic view of a heating module 10. The heating module 10 comprises a heating element 11 and a spring element 12 for R.414210

[0061] - 12 -

[0062] Transmission of a contact force F to the heating element 11. The spring element 12 comprises at least one spring section 13, wherein the spring section 13 has a wave shape. Fig. 2 shows a schematic view of a spring section 13 in this context to illustrate its shape and contact with the heating element 11. The wave shape of the spring section 13 comprises at least one wave crest 14 facing away from the heating element 11 and at least two wave troughs 15 facing the heating element 11. The spring section 13 is in contact with the heating element 11 at two contact areas KB formed by the wave troughs 15.

[0063] The wave crest 14 is formed as a region of the spring section 13 in which, starting from a longitudinal axis L of the spring section 13, the material of the spring section 13 rises in a first direction relative to the longitudinal axis L in the direction of a crest S of the wave crest 14 and then descends again in the direction of the longitudinal axis L. The wave troughs 15 are formed as regions of the spring section 13 in which, starting from the longitudinal axis L of the spring section 13, the material of the spring section 13 rises in a second direction opposite to the first direction relative to the longitudinal axis L in the direction of a crest S of the wave trough 15 and then descends again in the direction of the longitudinal axis L.

[0064] Figure 2 shows that a contact force F applied to the heating module 10 via the crest 14 of the spring section 13 is distributed by the wave shape of the spring section 13 to the contact areas KB formed by the troughs 15. This allows for an advantageous distribution of the contact force F over the heating element 11, resulting in improved contact of the heating element 11 with a thermal mass 51 and thus more efficient heat transfer between the heating element 11 and the thermal mass 51.

[0065] Fig. 2 further shows that in the spring section 13, a beginning A and an end E of the spring section 13 have a smaller distance to the longitudinal axis L of the spring section 13 than at least the respective crests S of the wave crest 14 and the wave troughs 15. R.414210

[0066] - 13 -

[0067] Fig. 3 shows an isolated view of the spring element 12 from Fig. 1. It can be seen that the spring element 12 comprises a plurality of adjacent spring sections 13. The spring sections 13 are identical and connected to each other via a fastening section 20. By using several spring sections 13, an improved, and in particular a more uniform, distribution of a contact force F applied to the heating module 10 can be achieved through an increased number of contact areas KB.

[0068] Fig. 4 further shows a schematic sectional view of a heating module 10 according to Fig. 1. It can be seen that the heating assembly 11 comprises at least one heating element 16. The heating element 16 is designed as a PTC element and is arranged between two busbars 17 enclosed by the heating assembly 11, such that the heating element 16 is in contact with the busbars 17 via a contact surface on each side. The heating assembly 11 also includes an insulating sheath 18 for electrically insulating the spring element 12 from the heating assembly 11, with the contact areas KB being formed on the insulating sheath 18. The heating assembly 11 further includes a support element 19, wherein the heating element 16, the busbars 17, the insulating sheath 18, and the spring element 12 are arranged on the support element.

[0069] As can be seen from Fig. 4, the contact areas KB are arranged in overlap with the heating element 16, so that a contact force F introduced into the spring section 13 is transferred to the heating element 16. In particular, the contact areas KB are arranged at a distance from the edge of the heating element.

[0070] Fig. 4 also shows that in the spring section 13, all contact areas KB formed by the wave troughs 15 are arranged in overlap with the same heating element 16. Accordingly, a contact force F applied to the spring section 13 is distributed over the extent of the heating element 16. Alternatively, several heating elements 16 can be arranged adjacent to each other along the longitudinal extent or longitudinal axis L of the spring section 13 (R.414210).

[0071] - 14 - are arranged to each other so that all contact areas KB formed by the wave troughs 15 are arranged in overlap with different heating elements 16.

[0072] Fig. 5 further shows a schematic view of a spring section 13. In the upper region of Fig. 5, the spring section 13 is unloaded, while in the lower region it is subjected to a contact force F. At the apexes S of the wave troughs 15, the spring section 13 exhibits a linear profile, at least in sections. This refers to the unloaded state of the spring section 13. In this way, when the spring section 13 is pre-tensioned by applying the contact force F, a curvature can be created in the linearly oriented sections, forming two contact areas KB within each of these areas. Accordingly, an improved distribution of the contact force F on the heating element 11 can be achieved.

[0073] Fig. 6 further shows a schematic view of a water separator 50 for use in a fuel cell 60. The water separator 50 comprises a thermal mass 51 designed as a housing and a heating module 10, wherein the heating module 10 is arranged, at least partially, in conjunction with the thermal mass 51.

[0074] Figure 6 further shows that the heating module 10 is arranged in a receiving pocket 52 formed in the thermal mass 51. The receiving pocket 52 is undersized relative to the heating module 10, so that the spring sections 13 of the spring element 12 of the heating module 10 are pre-tensioned by the arrangement of the heating module 10 in the receiving pocket 52.

[0075] Fig. 7 further shows a schematic view of a fuel cell 60 comprising at least one water separator 50.

[0076] Fig. 8 further shows a schematic view of a vehicle 70 comprising at least one heating module 10.

Claims

1. R.414210 - 15 - Claims 1. Heating module (10), in particular for use in a fuel cell (60), comprising a heating element (11) and a spring element (12) for transmitting a contact force (F) to the heating element (11), characterized in that the spring element (12) comprises at least one spring section (13), wherein the spring section (13) has a wave shape, the wave shape comprising at least one wave crest (14) facing away from the heating element (11) and at least two wave troughs (15) facing the heating element (11), wherein the spring section (13) is in contact with the heating element (11) at at least two contact areas (KB) formed by the wave troughs (15).

2. Heating module (10) according to claim 1 , characterized in that the spring element (12) comprises a plurality of spring sections (13) arranged adjacent to each other, wherein in particular the spring sections (13) are connected to each other via a fastening section (20).

3. Heating module (10) according to one of the preceding claims, characterized in that the heating assembly (11) comprises at least one heating element (16), wherein the heating element (16) and the spring element (12) are positioned relative to each other such that at least one contact area (KB) is arranged in overlap with the heating element (16), wherein in particular the contact area (KB) is spaced away from an edge of the heating element (16). R.414210 - 16 - 4. Heating module (10) according to claim 3, characterized in that in at least one spring section (13) all through the The contact areas (KB) formed by the wave troughs (15) are arranged in overlap with the same heating element (16).

5. Heating module (10) according to claim 3 or 4, characterized in that in at least one spring section (13) all of the The contact areas (KB) formed by the wave troughs (15) are arranged in overlap with various heating elements (16).

6. Heating module (10) according to one of claims 3 to 5, characterized in that at least one heating element (16) is designed as a PTC element.

7. Heating module (10) according to one of the preceding claims, characterized in that at least one spring section (13) has at least one wave trough (15) having a linear profile, at least sectionally, in a vertex (S) of the wave trough (15).

8. Heating module (10) according to one of the preceding claims, characterized in that in at least one spring section (13) a beginning (A) and / or an end (E) of the spring section (13) has a smaller distance to a longitudinal axis of the spring section (13) than at least one crest of a wave crest (14) and / or wave trough (15). R.414210 - 17 - 9. Heating module (10) according to one of the preceding claims, characterized in that the heating assembly (11) comprises two busbars (17), wherein at least one heating element (16) is arranged between the busbars (17) and is in contact with the busbars (17) via a contact surface.

10. Heating module (10) according to one of the preceding claims, characterized in that the heating assembly (11) comprises an insulating sheath (18) for electrical insulation of the spring element (12) from the heating assembly (11), wherein the contact areas (KB) are formed on the insulating sheath (18).

11. Heating module (10) according to one of the preceding claims, characterized in that the spring element (12) is made of stainless spring steel.

12. Water separator (50) for use in a fuel cell (60), comprising a thermal mass (51) and at least one heating module (10) according to one of the preceding claims, wherein the heating module (10) is arranged, at least sectionally, in conjunction with the thermal mass (51).

13. Water separator (50) according to the preceding claim, characterized in that the heating module (10) is arranged in a receiving pocket (52) formed in the thermal mass (51), wherein the receiving pocket (52) has an undersize relative to the heating module (10), such that at least one spring section (13) is pre-tensioned by the arrangement of the heating module (10) in the receiving pocket (52). R.414210 - 18 - 14. Fuel cell (60) comprising at least one water separator (50) according to one of claims 12 or 13.

15. Vehicle (70) comprising at least one heating module (10) according to any one of claims 1 to 11.

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