Heating device and method for manufacturing a heating device

Abstract

The invention relates to a heating device (10) comprising: - at least one heating element (11), more particularly at least one PTC element; - at least two power supply devices (12); and - a heat exchanger body (13) having an outer surface (14) for releasing heat to an environment and a receiving cavity (15) for receiving the heating element (11);where the heating element (11) is disposed in the receiving cavity (15) and is thermally connected by conduction to the heat exchanger body (13), and where at least one spring element (16) is provided which is supported in at least one support region (17) of the heat exchanger body (13) and applies a clamping force towards the heating element (11) so that the heating element (11) is pressed against the current supply devices (12) and a base (22), more particularly a heat sink, of the heat exchanger body.

Description

[0001] The invention relates to a heating device and a method for manufacturing a heating device. A heating device according to the preamble of claim 1 is known, for example, from DE 10 2006 018 150.

[0002] From US 2005 / 0230377 A1, an auxiliary heater for a motor vehicle is known.

[0003] The heater has a plastic housing containing a layered structure of radiator elements and heat-emitting elements. This layered structure is held under tension by a spring element.

[0004] DE 10 2018 206 085 A1 relates to a similar electrical heating device with an open housing in which a layered structure is accommodated, wherein a spring element is slidably accommodated in the housing and has several spring tongues offset from each other in the direction of displacement.

[0005] DE 39 42 266 C1 discloses a PTC heating element with a support profile body and a PTC heating element arranged between two contact plates. A leaf spring is arranged on grooves of the support profile body such that a contact pressure is applied to the upper wall of the profile body.

[0006] EP 0 333 906 A1 describes a similar device, wherein a cover plate and, additionally, a spring plate above the cover plate are inserted into retaining rails of the support profile body, wherein the spring plate is bulged out in the middle surface section and, in the inserted state, presses against the middle surface section of the cover plate, thereby ensuring the required thermal contact between the support profile body and the cover plate on the one hand and the PTC heating element on the other.

[0007] In control cabinets or small enclosures, such as camera housings or valve housings, temperature fluctuations cause condensation, which, together with dust and aggressive gases, can lead to corrosion. This increases the risk of operational failures due to leakage currents or flashovers. To ensure consistently optimal climatic conditions for the proper functioning of the components in the control cabinet or small enclosure, heaters or fan heaters, especially PTC semiconductor heaters, are used, and these must meet high standards of reliability and durability.

[0008] Such heating devices are typically equipped with electric heating elements. The mounting of these heating elements is designed to ensure both efficient heat transfer and consistent, secure fixation. Frequent and, depending on operating conditions, significant temperature fluctuations can lead to material fatigue due to aging, resulting in a reduction of the holding force with which the heating elements are fixed. This impairs heat transfer. If the holding function fails completely, the device may even fail entirely.

[0009] In the aforementioned DE 10 2006 018 150 or DE 39 42 266 C1, for example, heating elements are arranged in a heat exchanger body. The heat exchanger body is plastically deformed in such a way that the heating elements are held within it. The heat exchanger body encloses the receiving cavity for the heating elements.

[0010] The invention is based on the objective of providing a heating device in which, through an improved design, heating performance and operational reliability are increased, and manufacturing is simplified. Furthermore, the invention is based on the objective of providing a method for manufacturing such a heating device.

[0011] According to the invention, this problem is solved with regard to the heating device by the subject matter of claim 1. With regard to the method, the aforementioned problem is solved by the subject matter of claim 8.

[0012] Specifically, this task is solved by a heating device comprising at least one heating element, in particular at least one PTC element, at least two power supply devices, and a heat exchanger body. The heat exchanger body has an outer surface for dissipating heat to the environment and a receiving cavity for accommodating the heating element. The heating element is arranged in the receiving cavity and thermally connected to the heat exchanger body. Additionally, at least one spring element is provided, which bears against at least one support area of ​​the heat exchanger body and applies a clamping force towards the heating element via at least one pressure element such that the heating element is pressed against the power supply devices and a base, in particular a heat sink, of the heat exchanger body.

[0013] The heating element is positioned between the two power supply units to form a sandwich structure. In other words, the heating element and the power supply units are arranged layer by layer, with the heating element sandwiched between them. This has the advantage that, during the manufacturing process, the individual layers can be easily inserted into the receiving cavity of the heat exchanger body. Alternatively, the sandwich structure can be pre-assembled before being placed into the receiving cavity. Overall, the sandwich-like construction simplifies the manufacturing of the heating element.

[0014] The spring element rests against an inner surface of the support area facing the receiving cavity and clamps the heating element and / or the power supply components against the base, in particular the heat sink, of the heat exchanger body. This ensures that the heating element or the sandwich pack is securely held in the receiving cavity of the heat exchanger body.

[0015] The invention has several advantages. The tension force of the spring element securely presses the heating element against the power supply lines and the base of the heat exchanger body, even in the event of material fatigue of the heat exchanger body, particularly in the support area. The spring element is supported by the support area. In other words, the spring element rests against the support area for support. The spring element is therefore a separate component from the heat exchanger body. In other words, the spring element is structurally separated from the heat exchanger body. The support area provides a counter-bearing for the spring element to exert its tension force on the heating element and / or the power supply components. These components are pressed against the base of the heat exchanger body by the tension force of the spring element. The tension force of the spring element thus acts in the opposite direction to the support area of ​​the heat exchanger body, towards the heating element.Preferably, the heating element is pressed elastically, in particular resiliently, against the power supply devices and the base of the heat exchanger body by the spring element.

[0016] Furthermore, the operational reliability of the heating device according to the invention is increased because the spring element compensates for tolerances occurring, for example, due to material fatigue, and thus prevents the contact between the heating element and the power supply devices from breaking down, even under increased fatigue conditions. This significantly reduces the risk of heating device failure.

[0017] In general, material fatigue of the heat exchanger body, particularly in the support area, can occur due to frequent and / or large temperature changes, leading to a reduction in the contact force with which the heating element is fixed. The tension force of the spring element prevents this in the heating device according to the invention.

[0018] The invention has the further advantage that, by appropriately designing the spring element, the tension force in the direction of the heating element, and thus the contact force between the heating element and the power supply devices as well as the base of the heat exchanger body, can be adjusted to meet specific requirements. In other words, the use of the spring element enables different configurations of the heating device. The heating device is therefore versatile.

[0019] The spring element ensures that the heating element maintains a constant contact force with the power supply components throughout the heating unit's lifespan, or rather, that the heating element is pressed against the base of the heat exchanger body with a constant pressure. This results in a constant heating output from the heating unit, allowing for a uniform and controlled temperature control in the area surrounding the heating unit.

[0020] The heating element is preferably a PTC element. PTC stands for "Positive Temperature Coefficient" and means that the heating element in this design has a positive temperature coefficient. The PTC element can be described as a temperature-dependent resistance element.

[0021] The heating element is preferably pressed indirectly against the base of the heat exchanger body by at least one of the power supply devices. In other words, at least one of the power supply devices is preferably arranged between the heating element and the base of the heat exchanger body. Thus, there is no direct contact between the heating element and the base of the heat exchanger body. The base preferably forms a heat sink for temperature regulation of the heat exchanger body.

[0022] The spring element is pre-tensioned in and / or on the heat exchanger body, particularly in the direction of the heating element. The spring element is indirectly connected to the heating element.

[0023] The support area can have at least one contact surface for the spring element. The support area is formed by a bending tab that extends from at least one side wall of the heat exchanger body towards the center of the heat exchanger body and runs along a longitudinal direction of the side wall. The heating device thus has a longitudinal extension whose longitudinal direction runs parallel to this.

[0024] The spring element preferably rests at least partially against the support area. For this purpose, the spring element can have a lateral, particularly elongated, contact section. The spring element can be in line contact, point contact, and / or surface contact with the support area.

[0025] Preferred embodiments of the invention are specified in the dependent claims.

[0026] Preferably, the heating element is plate-shaped. The power supply devices preferably have at least one plate-shaped section that is in contact with the heating element.

[0027] Preferably, the spring element clamps the heating element and the power supply components against the base of the heat exchanger body. In other words, the spring element clamps the sandwich assembly against the base of the heat exchanger body. The clamping force of the spring element thus acts indirectly on the base of the heat exchanger body. The inside of the support area faces the heating element, so the spring element applies the clamping force in the direction of the heating element. Therefore, the inside of the support area also faces the base of the heat exchanger body. The base of the heat exchanger body defines the bottom boundary of the receiving cavity. More preferably, the base has at least one mounting area for attaching the heating element to a counterpart, in particular an external mounting device.

[0028] In summary, the heat exchanger body preferably has two side walls for laterally defining the receiving cavity and a base for defining the bottom of the receiving cavity. On one side opposite the base, the heat exchanger body is preferably open to the outside to accommodate the spring element.

[0029] According to the invention, the support area is formed by a tab that extends from at least one side wall of the heat exchanger body towards the center of the heat exchanger body and runs along a longitudinal direction of the side wall. The tab forms the abutment for the spring element. The tabs form support areas on both sides that hold the spring element securely in the receiving cavity. Thus, the tabs securely hold the spring element, and consequently the sandwich assembly, in the receiving cavity.

[0030] The tabs are bent tabs. In other words, during manufacturing, the tabs are bent, particularly using caulk technology, towards the center of the heat exchanger body. The tab can extend at least partially along the length of the heating element. The tab can be continuous. Alternatively, the tab can be segmented.

[0031] At least one clamping element is arranged between the spring element and one of the power supply devices to transfer the clamping force from the spring element to the heating element and at least one of the power supply devices. The spring element preferably applies the clamping force to the heating element and / or at least one of the power supply devices perpendicular to the clamping surface. In other words, the line of action of the clamping force is normal to the at least one clamping surface of the heating element and / or the power supply devices. Particularly preferably, the spring element applies the clamping force to the heating element and both power supply devices perpendicular to the clamping surface. In this way, the clamping force is introduced into the heating element or the power supply devices as efficiently as possible, resulting in increased heating power.

[0032] Preferably, the heat exchanger body has two opposing side walls, each with a support area for the spring element. In other words, the heat exchanger body has two opposing support areas against which the spring element bears. The side walls define the lateral boundaries of the receiving cavity. In this embodiment, the spring element rests against two support areas of the heat exchanger body. This ensures stable contact between the spring element and the heat exchanger body and distributes the spring element's support force, which corresponds to the tension force, over two support points.

[0033] According to the invention, at least one pressure element is arranged between the spring element and one of the power supply devices. The pressure element preferably transmits the clamping force from the spring element to the heating element and / or to at least one of the power supply devices, or to the sandwich assembly. The pressure element serves as a force transmission element to transfer the clamping force gently and evenly, particularly over a surface, to the adjacent power supply device. This increases the service life of the heating device. The pressure element has a concave shape in a region facing the spring element, against which the spring element rests. This allows the pressure element to absorb the spring force or the clamping force of the spring element more effectively. The pressure element can be made of solid material. Alternatively, the pressure element can be designed as a structural component with cavities. Preferably, the pressure element is made of aluminum.

[0034] According to the invention, the spring element has an arc-shaped cross-section with a convex form. The spring element has a vertex region that faces the heating element for transmitting the clamping force. Due to the convex shape of the spring element, the clamping force is transmitted particularly precisely to the adjacent pressure part via the vertex region. Furthermore, this allows the spring element to be easily pre-tensioned against the adjacent pressure part, namely by bending the tabs inwards, i.e., towards the center, after the spring element has been inserted into the receiving cavity. This causes the spring element to be elastically deformed.

[0035] According to the invention, the spring element is a leaf spring. Additionally or alternatively, the respective power supply device includes an electrode. The electrode can be an aluminum electrode. Additionally or alternatively, the heat exchanger body can also be made of aluminum. The advantage here is that the components are inexpensive to manufacture, thus reducing the overall cost of the heating device.

[0036] In a preferred embodiment, the receiving cavity is closed at its end face by at least one cover, in particular made of plastic. The cover preferably engages, at least partially, in an inner contour of the heat exchanger body in a form-fitting manner. Preferably, both end faces of the receiving cavity are closed by a cover in a form-fitting, in particular self-clamping, manner. The inner contour of the heat exchanger body can have several round recesses into which the cover engages. For this purpose, the cover preferably has polygonal projections that are in line or point contact with the respective recess. It is advantageous that additional fastening means, such as screws, clamping devices, etc., can be omitted. Furthermore, the polygonal projections of the cover inserted into the round recesses form a stable and secure one-time connection between the cover and the heat exchanger body.During the joining process, the polygonal projections of the lid are pressed into the round recesses, creating a press fit. Increased friction exists between the polygonal projections and the round recesses. Furthermore, any existing tolerances are compensated for in this process.

[0037] Preferably, at least one insulating device is arranged between the heat exchanger body and the sandwich core. Preferably, the sandwich core is at least partially, and in particular completely, encased with an insulating film.

[0038] According to dependent claim 8, the invention relates to a method for manufacturing a heating device according to the invention, wherein at least one heating element, at least two power supply devices and a heat exchanger body with a receiving cavity are provided; the heating element is arranged between the two power supply devices to form a sandwich pack, which is then encased with an insulating film; the sandwich pack is inserted into the receiving cavity in such a way that the heating element is in thermally conductive contact with the heat exchanger body; at least one spring element, in the form of a leaf spring, is inserted into the receiving cavity, the leaf spring having a convex shape;At least one pressure element is arranged between the spring element and one of the current supply devices, wherein the pressure element has a concave shape in a region facing the leaf spring, and at least one support region of the heat exchanger, in the form of a tab for preloading the spring element, is plastically deformed, in particular bent, such that the spring element exerts a clamping force in the direction of the heating element via the pressure element and presses the heating element against the two current supply devices and a base, in particular a cooling element, of the heat exchanger body.

[0039] The plastic deformation of the heat exchanger body, specifically the support area, advantageously allows for adjustment of the spring element's clamping force. The clamping force of the spring element depends on the degree of plastic deformation, particularly the bending angle of the support area after bending. Furthermore, plastic deformation offers the advantage of compensating for tolerances between the spring element, the heat exchanger body, and any clamping component. Additionally, it enables edge-free assembly and increased curvature of the spring element, resulting in improved spring element tension and thus increased heat transfer.

[0040] The advantages of the method for manufacturing a heating device are described in the section on the heating device. Furthermore, the method may alternatively or additionally include one or a combination of several of the features previously mentioned in relation to the heating device.

[0041] The invention is explained in more detail below with reference to the accompanying drawings. The illustrated embodiments represent examples of how the heating device according to the invention can be designed.

[0042] These show, Fig. 1 a perspective view of a heating device according to a preferred embodiment of the invention; Fig. 2 a cross-section through the heating device according to Fig. 1 ; and Fig. 3 a longitudinal section through the heating device according to Fig. 1 .

[0043] In the following, the same reference numbers are used for identical and equivalent parts.

[0044] Fig. 1 Figure 1 shows a heating device 10 according to a preferred embodiment of the invention. The heating device 10 comprises a heating element 11, two power supply devices 12, and a heat exchanger body 13. Furthermore, a spring element 16 is provided, which applies a clamping force in the direction of the heating element 11 and thus ensures a contact between the heating element 11 and the two power supply devices 12. The spring element 16 will be discussed in more detail later.

[0045] The heat exchanger body 13 comprises an outer surface 14 with longitudinal fins and a receiving cavity 15. The outer surface 14 serves to dissipate heat to the environment. The heat exchanger body 13 is thermally connected to the heating element 11 for heat transfer. The receiving cavity 15 accommodates the heating element 11. Furthermore, the power supply devices 12 are partially arranged in the receiving cavity 15. This is shown in the Fig. 2 and 3 Clearly visible. The power supply devices 12 will be discussed in more detail later.

[0046] The heat exchanger body 13 has a base 22 and two opposing side walls 23. The side walls 23 project from the base 22. The side walls 23 laterally define the receiving cavity 15, and the base 22 defines the receiving cavity 15 at the bottom. Together, the side walls 23 and the base 22 form a U-shaped profile. The receiving cavity 15 is thus bounded on three sides. Furthermore, the receiving cavity 15 is open to the outside on one side 34 of the heat exchanger body 13 opposite the base 22. Each side wall 23 has a free end 35. The free ends 35 of the side walls 23 are located on the opposite side 34.

[0047] The heat exchanger body 13 is an extruded profile. The side walls 23 and the base 22 are formed in one piece.

[0048] In Fig. 1 and 3It is evident that the heat exchanger body 13 is elongated. In other words, the heat exchanger body 13 has a longitudinal extent. The heat exchanger body 13 has a longitudinal axis L that runs centrally between the two side walls 23 in the longitudinal direction of the heat exchanger body 13.

[0049] As in Fig. 2 and 3 As shown, the heating element 11 and the power supply devices 12 are arranged in the receiving cavity 15. Each power supply device 12 has an electrode 27. The electrodes 27 comprise aluminum. Other electrode materials are possible. The electrodes 27 are plate-shaped.

[0050] Furthermore, the power supply devices 12 each comprise an electrical conductor 32 connected to the associated electrode 27. Each electrode 27 has a longitudinal side with a U-shaped recess. This recess preferably serves to receive and connect the terminals of the electrical conductors 32. The recesses of the two electrodes 27 are offset from each other transversely to the longitudinal direction of the electrodes 27. For this purpose, the electrodes 27 are arranged rotated relative to each other, i.e., folded over, particularly due to the routing of the conductors 32 and any material accumulations. The electrodes 27 are contacted at their end faces to ensure the flatness of the electrodes 27, especially for plate-shaped electrodes 27. The flat shape of the electrodes 27 increases heat dissipation. The connection of the conductors 32 to the electrodes 27 is located in the Figures 1 to 3 not shown.

[0051] The heating element 11 according to Figs. 1 to 3 is a PTC element. In other words, the heating element 11 has a positive temperature coefficient. Hereinafter, the heating element 11 will be referred to as PTC element 11. As in Fig. 2 and 3 As can be clearly seen, the PTC element 11 is arranged between the two electrodes 27. The PTC element 11 is plate-shaped. Its outer dimensions are smaller at the narrow sides than those of the electrodes 27. In other words, the PTC element 11 has an outer contour that is offset inwards, particularly towards its own center, from the outer contour of the electrodes 27.

[0052] Specifically, the electrodes 27 and the PTC element 11 arranged between them form a sandwich assembly 19. This significantly simplifies the manufacturing and assembly of the heating device 10. The sandwich assembly 19 is arranged horizontally in the receiving cavity 15. The PTC element 11 and the electrodes 27 are each elongated. The PTC element 11 and the electrodes 27 extend longitudinally along the heat exchanger body 13.

[0053] Furthermore, the heating device 10 includes the aforementioned spring element 16. The spring element 16 is a leaf spring 26. The leaf spring 26 is a separate spring element. In other words, the leaf spring 26 is structurally separated from the heat exchanger body 13. The leaf spring 26 has an arc-shaped cross-section. In other words, the leaf spring 26 has a shell-shaped cross-section. Specifically, the leaf spring 26 has a convex shape in the direction of the heating element 11. The leaf spring 26 includes a vertex region 33, which forms a tension force transmission section in the direction of the heating element 11. Furthermore, the leaf spring 26 includes two lateral contact sections 36, with which the leaf spring 26 is supported against support areas 17 of the heat exchanger body 13. The support areas 17 will be discussed in more detail later.

[0054] The lateral contact sections 36 are opposing lateral ends of the leaf spring 26. The lateral contact sections 36, particularly the lateral ends, extend longitudinally along the heat exchanger body 13. The leaf spring 26 is elongated. The leaf spring 26 extends longitudinally along the heat exchanger body 13. In other words, the leaf spring 26 runs parallel to the side walls 23. The leaf spring 26 is arranged in the receiving cavity 15. Specifically, the leaf spring 26 is located on the side 34 opposite the base 22. The leaf spring 26 spans the receiving cavity 15 longitudinally along the heat exchanger body 13.

[0055] As mentioned above, the heat exchanger body 13 has support areas 17 on its side walls 23 for the lateral contact sections 36 of the leaf spring 26. The support areas 17 are formed by tabs 24 that are bent inwards transversely to the longitudinal direction on the side walls 23. In other words, the tabs 24 are folded over. The tabs 24 can also be referred to as bending tabs. The tabs 24 are an integral part of the side walls 23. Each tab 24 has an inner surface 21 facing the base 22. The leaf spring 26 rests against this inner surface 21 with its lateral contact sections 36 for support.

[0056] The tension of the leaf spring 26 can be adjusted by bending the tabs 24.

[0057] The tension of the leaf spring 26 depends on the bending angle of the tabs 24, at which the tabs 24 are bent inwards. Furthermore, the tabs 24 have the advantage of allowing for tolerance compensation between the leaf spring 26 and the heat exchanger body 13, as well as the pressure part 25 described later. Additionally, they enable flush mounting and increased curvature of the leaf spring 26, resulting in improved tension of the leaf spring 26 and thus increased heat output.

[0058] A pressure element 25 is arranged between the leaf spring 26 and the sandwich assembly 19. The pressure element 25 absorbs the clamping force from the leaf spring 26 and transmits this clamping force to the adjacent electrode 27. The pressure element 25 has a surface 37 facing the leaf spring 26, which is in contact with the apex region 33. The surface 37 of the pressure element 25 has a partially curved shape to accommodate the apex region 33 of the leaf spring 26. Specifically, the surface 37 of the pressure element 25 has a concave shape. Furthermore, the pressure element 25 may have notches on the surface 37.

[0059] The pressure element 25 is positioned against an inner contour 31 of the heat exchanger body 13 or slightly spaced from it. Specifically, the pressure element 25 can abut the opposite side walls 23. This ensures precise positioning of the pressure element 25 within the receiving cavity 15. The pressure element 25 is movably arranged in the direction of the clamping force. Furthermore, the pressure element 25 has chamfered edges along its longitudinal sides. The pressure element 25 is plate-shaped and made of solid material. Specifically, the pressure element 25 is made of aluminum.

[0060] As in Fig. 2 As shown, the sandwich pack 19 is surrounded by an insulating device 28. Specifically, the sandwich pack 19 is completely encased in an insulating film. The insulating film is thus arranged between the pressure part 25 and the heat exchanger body 13 and the sandwich pack 19 for electrical insulation.

[0061] The following describes the arrangement of the aforementioned individual components of the heating device 10 with the heat exchanger body 13 starting from the base 22 along an imaginary axis that is perpendicular to the base 22.

[0062] As in Fig. 2As can be clearly seen, the insulating film is arranged between the base 22 and one of the first of the two electrodes 27. The first electrode 27 rests flat against the insulating film. The PTC element 11 is arranged adjacent to the first electrode 27, and a second of the two electrodes 27 rests flat against it. The pressure element 25 is then arranged, with the insulating film located between the pressure element 25 and the second electrode 27. The pressure element 25 is in contact with the leaf spring 26, specifically with the apex region 33 of the leaf spring 26, on the side 34 of the heat exchanger body 13 opposite the base 22. The leaf spring 26 and the pressure element 25 are in direct contact for force transmission. To apply the clamping force, the leaf spring 26 is supported by its lateral contact sections 36 against the two tabs 24 of the heat exchanger body 13.

[0063] The leaf spring 26 rests against the inner surfaces 21 of the two tabs 24 to apply the clamping force in the opposite direction to the tabs 24. The tabs 24 project partially beyond the lateral contact sections 36 of the leaf spring 26 towards the center, particularly in the direction of the longitudinal axis L. The tabs 24 therefore each form an abutment for the lateral contact sections 36 of the leaf spring 26. The leaf spring 26 is elastically deformed between the pressure element 25 and the tabs 24 to create preload. Specifically, during the manufacture of the heating device 10, the leaf spring 26 is first pressed against the pressure element 25 and thus preloaded by folding or bending the tabs 24 towards the leaf spring 26. The force flow of the clamping force takes place from the leaf spring 26 via the apex area 33 to the pressure part 25, from the pressure part 25 to the sandwich pack 19 and then to the base 22 of the heat exchanger body 13.In other words, the leaf spring 26 clamps the sandwich assembly 19 against the base 22 via the pressure element 25. This ensures that the integrated components are held stably and securely in the receiving cavity 15. The insulating film is not mentioned here for the sake of simplicity.

[0064] The tension of the leaf spring 26 presses the PTC element 11 and the electrodes 27 together. This increases the heating power of the heating device 10 compared to conventional PTC heating element configurations. The tension of the leaf spring 26 acts perpendicular to two contact surfaces 18 of the PTC element 11, via which the PTC element 11 is in contact with adjacent contact surfaces 38 of the respective electrodes 27. The electrodes 27 and the PTC element 11 are in direct contact.

[0065] To achieve temperature regulation of the heating device 10, the base 22 forms a heat sink. The base 22 is, as in Fig. 1The base 22 is shown in a plate-like form. It projects outwards transversely to the longitudinal direction beyond one of the side walls 23. This projecting part of the base 22 forms a mounting area 39 for attaching the heating element 10, for example to an external mounting device. The mounting area 39 has at least two through-openings.

[0066] The heating device 10 has according to Fig. 1 Two covers 29 are installed, which close the receiving cavity 15 at its end faces. The electrical leads 32 of the power supply devices 12 are led outwards, in particular sealed form, through one of the covers 29.

[0067] The covers 29 serve to increase the suitability of the heating device 10 for various environmental conditions, for example, humid and / or dusty environments. Thanks to these covers 29, the heating device 10 has an increased IP protection rating.

[0068] The covers 29 each have projections 41 extending from a transverse side of the covers 29. The projections 41 each have a polygonal contour. Specifically, the projections 41 form polygonal pins that engage in round recesses 42 of the inner contour 31 of the heat exchanger body 13 to fasten the covers 29. The edges of the projections 41 are in line contact with the surfaces of the recesses 42. As in Fig. 2 As shown, the inner contour 31 of the heat exchanger body 13 has a total of four recesses 42, and the respective cover 29 has four projections 41. Such a plug-in connection is particularly advantageous with regard to durability and ease of assembly. Additionally, the covers 29 can be bonded to the heat exchanger body 13. Fig. 3 It can also be seen that the sandwich package 19 is spaced longitudinally from the two lids 29. Reference symbol list

[0069] 10 Heating device 11 Heating element, PTC element 12 Power supply devices 13 Heat exchanger body 14 Outer surface 15 Receiving cavity 16 Spring element 17 Support area 18 Contact surface of the heating element 19 Sandwich package 21 Inner side of the support area 22 Base 23 Side walls 24 Tab 25 Contact part 26 Leaf spring 27 Electrode 28 Insulation device 29 Cover 31 Inner contour of the heat exchanger body 32 Electrical leads 33 Vertex area 34 Side opposite the base 35 Free end 36 Lateral contact sections 37 First surface 38 Contact surfaces of the electrodes 39 Mounting area 41 Extensions 42 Recesses Longitudinal axis

Claims

1. Heating device (10) having at least one heating element (11), in particular at least one PTC element, at least two current supply devices (12) and a heat exchanger body (13) which has an outer surface (14) for releasing heat to an environment and a receiving cavity (15) for receiving the heating element (11), wherein the heating element (11) is arranged in the receiving cavity (15) and is connected to the heat exchanger body (13) in a thermally conductive manner, and at least one spring element (16) is provided, which is supported on at least one support region (17) of the heat exchanger body (13) and applies a clamping force toward the heating element (11) in such a way that the heating element (11) is pressed against the current supply devices (12) and a base (22), in particular a heat sink, of the heat exchanger body, wherein the heating element (11) is arranged between the two current supply devices (12) to form a sandwich package (19) and the support region (17) is formed by a tab (24) which extends from at least one side wall (23) of the heat exchanger body (13) towards the center of the heat exchanger body (13) and runs along a longitudinal direction of the side wall (23) and at least one pressing part (25) is arranged between the spring element (16) and one of the current supply devices (12), wherein the pressing part (25) transmits the clamping force from the spring element (16) to the heating element (11) and to at least one of the current supply devices (12) and wherein the spring element (16) is a pretensioned leaf spring (26) having a convex shape with an apex region (33) that faces the heating element (11), characterized in that the tab (24) is a bending tab and the pressing part (25) has a concave shape in a region facing the leaf spring (26), against which the apex region (33) of the leaf spring (26) rests.

2. The heating device (10) according to claim 1, characterized in that the spring element (16) rests against an inner side (21) of the support region (17) facing the receiving cavity (15) and braces the heating element (11) and / or the current supply devices (12), in particular the sandwich package (19), against the base (22) of the heat exchanger body (13).

3. The heating device (10) according to one of the preceding claims, characterized in that the heating element (11) is in contact with the current supply devices (12) through at least one pressing surface (18), wherein the spring element (16) applies the clamping force transverse to the pressing surface (18) to the heating element (11) and / or at least one of the current supply devices (12).

4. The heating device (10) according to one of the preceding claims, characterized in that the heat exchanger body (13) has two oppositely arranged side walls (23), on each of which the support region (17) for the spring element (16) is formed.

5. The heating device (10) according to one of the preceding claims, characterized in that the respective current supply device (12) comprises an electrode (27), in particular an aluminum electrode.

6. The heating device (10) according to one of the preceding claims, characterized in that the receiving cavity (15) is closed at the front end by at least one cover (29), wherein the cover (29) engages positively at least in sections in an inner contour (31) of the heat exchanger body (13).

7. The heating device (10) according to one of the preceding claims, characterized in that at least one insulating device (28), in particular an insulating foil, is arranged between the heat exchanger body (13) and the sandwich package (19).

8. A method for producing a heating device (10) according to one of claims 1 to 7, in which - at least one heating element (11), at least two current supply devices (12), and a heat exchanger body (13) having a receiving cavity (15) are provided; - the heating element (11) is arranged between the two current supply devices (12) to form a sandwich package (19), which is then sheathed with an insulating device (28); - the sandwich package (19) is inserted into the receiving cavity (15) in such a way that the heating element (11) is in connection with the heat exchanger body (13) in a thermally conductive manner; - at least one spring element (16) is inserted into the receiving cavity (15), wherein the spring element (16) is a pretensioned leaf spring having a convex shape; - at least one pressing part (25) is arranged between the spring element (16) and one of the current supply devices (12), wherein the pressing part (25) has a concave shape in a region facing the leaf spring, - at least one support region (17) of the heat exchanger in the form of a tab (24) is plastically deformed, in particular bent over, to pretension the spring element (16) in such a way that the spring element (16) applies a clamping force via the pressing part (25) in the direction of the heating element (11) and presses the heating element (11) against the two current supply devices (12) and a base (22), in particular a heat sink, of the heat exchanger body (13).

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