Electric heater for a vehicle

Abstract

An electric heater (100) for a vehicle, comprising - at least two heating modules (101), wherein a heating module (101) comprises at least one heating element (106) arranged between two contact electrodes (107) and electrically insulated from a surrounding tube (109) by an insulation (108), wherein heat-transferring elements (110) are attached to the outer surface of the tube (109), - an electronic housing (104), wherein the at least two heating modules (101) project into the electronic housing (104) through at least one opening (115) and wherein the opening (115) in the electronic housing (104), through which a heating module (101) projects, is sealed by a seal (103), and - at least two conductor elements (102) arranged inside the electronic housing (104), characterized in that - a first heating module (101a) through a first conductor element (102a) and - a second heating module (101b) is electrically connected to the electronic housing (104) by a second conductor element (102b).

Description

[0001] The invention relates to an electric heater for a vehicle according to the preamble of the independent claim. Furthermore, a method for manufacturing the same is claimed according to the preamble of the dependent claim.

[0002] EP 4 243 568 A1 discloses an electric heating device with at least two heating modules and a control housing containing power electronics, wherein the electrically conductive outer shell of each heating module is electrically connected to the base of the control housing by an electrical conductor arrangement at a side surface of the outer shell projecting into the interior of the control housing. The electrical conductor arrangement comprises at least one electrically conductive intermediate element and a cover that covers the intermediate element in the direction opposite to the base of the control housing. A method for manufacturing the described heating device and a motor vehicle with the described heating device are also disclosed.

[0003] US 2004 / 0112884A1 discloses an electric heating system for motor vehicles comprising one or more electric heating elements, a control circuit arranged in a housing with one or more power semiconductors mounted on the control circuit for controlling the power radiated by the heating elements, and a metal plate designated as ground potential, which is arranged on the side of the circuit board facing away from the power semiconductor and is rigidly connected to the circuit board and electrically insulated from the conductor tracks located on the underside of the circuit board. One or more heat sinks are provided outside the housing, and the metal plate is connected to the at least one heat sink located outside the housing by thermally conductive connectors.

[0004] CN 1 03 179 700 A discloses a heat-generating element with a positioning frame forming a recess in which at least one PTC element is received, and two contact plates abutting opposite sides of the PTC element, as well as a sheet metal cover of the PTC element connected to the positioning frame. Furthermore, an electric heating device is disclosed, comprising a frame forming an opening on opposite sides for the passage of a medium to be heated, and a layered structure arranged in the frame comprising layers of corrugated fins and heat-generating elements, wherein the heat-generating element has at least one PTC element arranged between two parallel contact plates and is provided on both sides with a sheet metal cover arranged between the corrugated fin elements and the contact plate.

[0005] EP 4 242 547 A1 discloses an electric heating device with at least two heating modules, a control housing and power electronics arranged therein for supplying the heating modules with electricity, as well as an electrically conductive conductor arrangement with a rail from which an arm protrudes, which electrically connects an electrically conductive outer shell of the respective heating module to the housing. A motor vehicle with such an electric heating device is also disclosed.

[0006] KR 10 1 115 952 B1 discloses a power supply structure for an electronic heating device with several flat tubes, wherein a section of the outer surface of the flat tube protrudes from a frame, and wherein a first wire is connected to the protruding outer surface of each flat tube in such a way that a negative terminal can be applied to it. The flat tube further comprises a heating medium built into it and a heating medium connector protruding by a predetermined length, wherein a second wire is connected to the protruding heating medium connector in such a way that a positive terminal can be applied to it. An insulating element is arranged on the outer surface of the frame such that the electrical connection positions of the first wire and the second wire are separated by their positioning above and below the insulating element, respectively.

[0007] US 2021 / 0045194A1 discloses an electric heating device comprising a housing with a partition separating a connection chamber from a heating chamber for heat dissipation, from which at least one PTC heating element with a heating element housing projects toward the heating chamber, in which at least one PTC element and conductive traces of opposite polarity for supplying current to the PTC element, which are electrically connected in the connection chamber, are insulated and supported, as well as a retaining element encompassing the heating element housing, which is connected to the partition on its side facing the heating chamber and to the heating element housing. A method for manufacturing such an electric heating device is also disclosed.

[0008] US 2005 / 0205552A1 discloses an electric heating device with a plurality of radiant elements, each having a radiant fin and a radiant fin support plate surrounding the radiant fin, which is integrally brazed with the radiant fin, a plurality of flat tubes arranged between the radiant elements and containing heating elements for generating heat when electrical energy is supplied, as well as first and second support frames arranged opposite each other on the sides of the outermost radiant elements to support and fix the radiant elements and the flat tubes, and first and second caps to support the two end sections of the first and second support frames and both end sections of the flat tubes.

[0009] EP 1 338 451 A2 discloses an electric air heating device, particularly for a motor vehicle, comprising electric heating elements for heating the air and a housing that includes a ground connection, an electrical supply connection, and an electronic circuit for controlling the power supply to the heating elements. Within the housing, the heating elements are arranged in electrical contact with the ground connection and the electrical supply connection. The housing is made of an electrically conductive material and is formed in one piece with the molded-on ground connection. The heating elements and the electronic circuit are arranged in direct electrical contact with the housing.

[0010] EP 3 904 781 A1 discloses an electric heating device for heating a fluid, comprising a heating module and a control housing, wherein the heating module has an outer casing made of metal or an alloy and surrounds at least one heating element, and wherein the control housing contains power electronics for supplying electrical power to the heating module. According to this application, the control housing has a through-opening through which the heating module is guided and a sealing arrangement located in the through-opening, which fluidically seals the power electronics against the fluid and electrically insulates the control housing from the heating module casing.

[0011] EP 3 493 650 A1 discloses an electric heating device with a frame in which a power part is arranged, which has corrugated fin elements and heat-generating elements, each comprising at least one PTC element arranged between contact plates, which is covered on the outside by insulation and received in a flat tube, wherein the corrugated fin elements are sealed on the outside of the flat tubes at their connection side and are passed through a control housing, and wherein the control housing is provided with a conductor element that electrically connects several flat tubes to each other.

[0012] The present invention addresses the problem of designing the described electric heater in a modular manner, thus making it flexibly adaptable to the requirements of different vehicle applications. Simultaneously, the invention aims to improve personal safety, in particular by reducing the risk of electrical accidents caused by contact with live components in the event of malfunctions.

[0013] The invention relates to an electric heater for a vehicle for heating a fluid, wherein the heater consists of several heating modules, each of which is electrically connected to the vehicle's ground connection by a conductor element. Furthermore, a method for manufacturing said electric heater is part of the invention.

[0014] The invention relates to an electric heater for a vehicle, comprising at least two heating modules, each heating module including at least one heating element arranged between two contact electrodes and electrically insulated from a surrounding tube by insulation, with heat-transferring elements being mounted on the outer surface of the tube. The electric heater also has an electronics housing in which power electronics are arranged, the at least two heating modules projecting at least partially into the housing through openings in the housing, and at least one opening through which a heating module projects is sealed by a gasket. Furthermore, the heater has at least two conductor elements arranged inside the housing. According to the invention, at least one heating module is electrically connected to the housing by a conductor element.

[0015] An electric heater is used to heat fluids used during vehicle operation, such as air or coolant. Heating elements are supplied with an electrical voltage, causing them to heat up. The heating element can be a ceramic stone with a PTC effect or a resistance heating layer applied to an insulating substrate. To ensure efficient heat transfer to the fluid while simultaneously guaranteeing operational reliability and durability, the heating elements are housed in heating modules. A heating module comprises at least one heating element positioned between two contact electrodes and electrically insulated from a surrounding tube, such as a flat tube. Each contact electrode has at least one terminal protruding from one end of the tube, which serves to supply the electrical voltage.At least one heat-transferring element, such as a corrugated fin, is attached to the outside of the tube. This element is surrounded by the fluid and exchanges heat with it. Each tube has an upper and a lower end, each of which can be individually sealed, for example, by a plug, a gasket, or a component that aligns and simultaneously seals multiple tubes. The upper end is the end where the connecting tabs of the contact electrodes protrude from the tube. The tube is preferably made of a metallic material, particularly an aluminum alloy, to ensure ideal heat transfer from the heating element to the heat-transferring element.The insulation between the contact electrodes and the pipe can be provided, for example, by a ceramic plate or a film, and normally ensures that both the pipe and the heat transfer element are de-energized during operation. However, in the event of a malfunction, this insulation may fail, for example, due to damage to the insulation or unintentional fluid ingress into the pipe, causing the pipe or the heat transfer element to become live components. If touched by a person, this could lead to an electric shock.

[0016] Furthermore, the electric heater has an electronics housing, which preferably defines an internal electronics compartment by means of a fluid-tight cover. The electronics housing is preferably made of an electrically conductive material, particularly preferably a metal, for example, aluminum or an aluminum alloy. Alternatively, the electronics housing can also be made of an electrically non-conductive material, for example, a plastic. In this case, the electronics housing is at least partially coated with an electrically conductive layer or another electrical conductor to establish the electrical contact according to the invention with the neutral conductor or ground connection of the vehicle. The internal electronics compartment preferably houses control electronics, which serve to control and supply power to the respective heating modules.Alternatively, the power electronics can also be located outside the electronics housing. A battery, for example, can serve as the voltage source. The voltage for operating the heater is preferably in the high-voltage range, i.e., above 48V, and particularly preferably above 240V. To enable electrical contact between the power electronics and the heating modules, the electronics housing also has a number of openings, preferably corresponding to the number of heating modules. The at least two heating modules protrude at least partially through the openings into the interior of the electronics and are electrically connected to the power electronics there. The space between the opening and the heating module is fluidically sealed by a sealing element, for example, a silicone gasket, to isolate the interior of the electronics from the fluid and the environment.Preferably, the electronic housing is made of an electrically conductive metallic material. To prevent the electronic housing from becoming live in the event of a malfunction, it is connected to the vehicle's neutral conductor or ground connection. This prevents the possibility of an electric shock if a person touches it.

[0017] Furthermore, at least two conductor elements are arranged inside the housing according to the invention such that a first heating module is electrically connected to the housing by a first conductor element and a second heating module is electrically connected to the housing by a second conductor element. Preferably, the number of conductor elements corresponds to the number of heating modules, so that each heating module is electrically connected to the housing by an associated conductor element. The conductor elements can be identical in construction and / or adapted to the geometry of the heating module, the electronic housing, or another component. Furthermore, the conductor elements can differ geometrically or with regard to the material used. For functional reasons, the conductor element consists of an electrically conductive material, preferably a metal, for example, copper or aluminum. Preferably, the conductor element is designed as a thin plate, for example, as a stamped or pressed part.

[0018] The arrangement of heating module and conductor element according to the invention allows electric heaters for different vehicle applications to be manufactured using the same heating module, without the need to design special conductor elements for each vehicle application. Instead, the number of heating modules can be adjusted depending on the required heating power, with only the electronics housing needing to be adapted to the number of heating modules.

[0019] Alternatively, the electronic housing can be made of an electrically non-conductive material, preferably a non-metallic material, such as a plastic. In this case, the electronic housing has an electrically conductive busbar arranged such that the at least two conductor elements are electrically in contact with the busbar instead of the electronic housing itself and are connected to the vehicle's ground connection via the busbar. The busbar can be made of a metallic material and be attached to the electronic housing as a separate component, or it can be positively or materially bonded to the electronic housing, for example by casting or overmolding, or applied to the electronic housing as a coating.

[0020] In a first advantageous embodiment, at least one of the at least two conductor elements has one or more contact lugs. These serve for electrically contacting the conductor element with, for example, the housing or the heating module, or for mechanically fixing the conductor element itself. Many embodiments are conceivable, so that the individual conductor elements can have a different number and design of contact lugs. Preferably, at least one of the at least two conductor elements has at least one module contact lug with which the conductor element is electrically connected to a heating module. Alternatively or additionally, the conductor element has at least one housing contact lug with which the conductor element is electrically connected to the electronics housing.

[0021] In the alternative embodiment already mentioned, in which the electronic housing is made of an electrically non-conductive material, the housing contact tab is preferably designed such that it electrically contacts the electronic housing at the busbar provided there.

[0022] Preferably, at least one contact lug of a conductor element consists of at least one sheet metal spring which is tensioned in the installed state and the resulting spring force ensures an electrical contact between the conductor element and the adjacent component.

[0023] The contact tab is preferably designed as a thin metal strip which comes into contact with the heating module during installation and is thereby elastically bent. Since the bending occurs within the elastic range of the metal strip, the spring force continuously presses the metal strip against the outer surface of the heating module, thus ensuring electrical contact between the heating module and the conductor element at all times. The contact tab therefore acts like a spring steel strip. When dimensioning the metal strip, care must be taken to ensure that the bending during the installation process does not result in predominantly plastic deformation.

[0024] Particularly preferred is the design of at least one contact lug of at least one conductor element such that the spring force vector of the tensioned contact lug is predominantly perpendicular to the surface of the component electrically connected to the conductor element, for example, the outer surface of the heating module or the surface of the electronic housing. This ensures electrical contact between the components even in the case of relative movements.

[0025] Particularly preferably, the at least one conductor element is geometrically designed such that it at least partially, preferably predominantly, and particularly preferably completely surrounds the heating module to which it is electrically connected. For example, with a rectangular tube cross-section of the heating module, this can be achieved by an L-, U-, or O-shape of the conductor element when viewed along the longitudinal axis of the heating module.

[0026] A conductor element designed in this way offers the advantage that the heating module can be contacted on several sides, in the example given here on two, three, or four sides. Furthermore, this allows for a preferred arrangement of several contact lugs such that the spring force vectors of several contact lugs of a conductor element meet at a single point, thereby stabilizing the conductor element in its position relative to the heating module.

[0027] In a preferred embodiment of the electric heater, the at least two conductor elements are connected to each other by an electrically non-conductive element. Preferably, the non-conductive element is mechanically connected to another component of the electric heater, for example, the electronics housing. The mechanical connection to the other component can be achieved, for example, by a screw, rivet, clip, press fit, or other form-fit or force-fit connection. The non-conductive element can, among other things, serve to secure the position of the conductor elements relative to each other or within the electronics housing and / or to maintain the deflection of the contact lugs and thus the electrical contact. Furthermore, the non-conductive element can also provide a sealing function for other components.Preferably, the non-conducting element consists of a non-conducting material, preferably a non-metallic material, for example a plastic.

[0028] Particularly preferred is the connection between the non-conductive element and the at least two conductor elements as a material-bonded connection, for example by overmolding or embedding the conductor elements in the non-conductive element. In this embodiment, the non-conductive element can serve as an assembly aid, since the conductor elements are pre-positioned relative to the non-conductive element and can be installed in the housing as a single component.

[0029] In a further preferred embodiment, the electric heater has a cover element which is arranged in the electronics housing such that it at least partially covers at least one heating module projecting into the housing towards the power electronics. Preferably, the cover element provides a fluid-tight seal for the upper end of the heating module tube projecting into the electronics housing, with corresponding openings provided for the contact electrodes of the heating modules towards the power electronics in order to establish electrical contact between the components. Particularly preferably, the cover element is mechanically connected to the electronics housing, for example by a screw or clip connection.Furthermore, the cover element can also serve as a positioning aid for the at least two heating modules relative to each other and / or the at least two conductor elements relative to each other and / or the at least two heating modules and the at least two conductor elements relative to each other during the manufacturing process. Preferably, the cover element is designed such that the power electronics touch the cover element or are at least partially supported on it. The cover element is preferably made of an electrically non-conductive material, preferably a non-metallic material, for example, plastic.

[0030] In an alternative embodiment, the electronics housing is made of an electrically non-conductive material. Instead of or in addition to the embodiment already described, in which the electronics housing has an electrically conductive busbar, the cover element can be made entirely or partially of an electrically conductive material, for example, a metallic material, and be electrically connected to the neutral conductor or ground connection of the vehicle. Alternatively or additionally, the cover element can have a busbar made of an electrically conductive material, preferably a metallic material. In this alternative embodiment, the at least two conductor elements are arranged such that the at least first and second heating modules each have an electrical connection to the electrically conductive area of ​​the cover element via the at least first and second conductor modules.The busbar of the cover element is connected instead of the electronics housing. As previously described, the busbar of the cover element can also be attached to the cover element as a separate component, or it can be positively or materially bonded to the cover element, for example by casting or overmolding, or applied to the cover element as a coating.

[0031] In a particularly preferred embodiment of the electric heater, at least one conductor element is mechanically connected to the cover element via at least one retaining element. Preferably, the retaining element is part of the conductor element, for example, a bent sheet metal element, and is shaped at its end such that a connection to the cover element can be made, for example, by means of a hook, clip, or shield shape and a corresponding counterpart for fastening to the cover element. Alternatively, a clip or clamp connection can also be used, for example. Particularly preferably, the cover element is used as an assembly aid for the at least two conductor elements, such that the conductor elements are first connected to the cover element and then the assembly is inserted into the interior of the housing.

[0032] In a further preferred embodiment of the heater, the cover element comprises at least one spacer element which, in the installed state, is arranged between the cover element and at least one conductor element. Preferably, the spacer element is part of the cover element. Alternatively or additionally, the spacer element is arranged such that it presses the at least one conductor element against the electronics housing and / or against the heating module to which it is electrically connected. This improves the electrical contact between the conductor element and the components electrically connected to it. Furthermore, this secures the position of the conductor element.

[0033] A method for manufacturing an electric heater for a vehicle is also claimed, comprising at least, but not exclusively, the following steps: - Providing at least two heating modules, wherein a heating module consists of at least one heating element arranged between two contact electrodes and electrically insulated from a tube housed therein and surrounding it by insulation, and at least one heat-transferring element attached to the outside of the tube. - Aligning at least two heating modules to an electronics housing, wherein the heating modules protrude through at least one opening into the interior of the electronics housing. - The installation of at least one seal in the space between the electronics housing and the outside of at least one heating module protruding through this opening. - Aligning and inserting at least one first conductor element opposite the first heating module and at least one second conductor element opposite the second heating module such that the first heating module is electrically connected to the electronics housing by the first conductor element and the second heating module is electrically connected to the electronics housing by the second conductor element.

[0034] It goes without saying that the order of the steps may need to be varied.

[0035] Alternatively, the manufacturing step of aligning and inserting the at least two conductor elements can be replaced by the following two steps: - The creation of a mechanical connection between at least two conductor elements and a cover element. - Inserting the cover element with the pre-assembled conductor elements into the electronics housing in such a way that a first heating module is electrically connected to the electronics housing by a first conductor element and a second heating module is electrically connected to the electronics housing by a second conductor element.

[0036] In a further alternative embodiment of the manufacturing process, the process includes an additional manufacturing step in which the at least two conductor elements are connected by an electrically non-conductive element before installation, for example by overmolding or overmolding. In this case, instead of aligning and inserting the at least two conductor elements relative to the heating modules, the non-conductive element to which the at least two conductor elements are connected is aligned and inserted relative to the two heating modules, so that they are electrically connected to the electronic housing via the respective conductor elements.

[0037] Further details and advantages of the present invention will become apparent from the following description of exemplary embodiments in conjunction with the drawings. These show: Fig. 1. A schematic representation of the main components of the heater, which are electrically connected to each other. Fig. 2 the schematic cross-section of a heating module for an electric heater, Fig. 3 a schematic cross-sectional view of the electronics housing, the heating module and the conductor element, Fig. 4 Three exemplary schematic cross-sections (a, b, c) of the arrangement of a conductor element relative to a heating module, Fig. 5 the schematic cross-section of a conductor element before (5a) and after (5b) the installation of the conductor element in the electric heater, Fig. 6 the schematic cross-section of a conductor element and the section of a cover element, Fig. 7. Excerpts of some components of an exemplary embodiment of an electric heater.

[0038] Fig. Figure 1 shows a schematic representation of the electrically interconnected main components of an electric heater (100). The heating modules (101, 101a, 101b) are visible, each mechanically and fluid-tight connected to the electronics housing (104) via a seal (103). To prevent the electronics housing from being exposed to an electrical voltage in the event of a fault, a permanent connection to the neutral conductor or the vehicle's ground connection (105) is maintained. However, due to the electrically insulating effect of the seal (103), the heating modules (101, 101a, 101b) are not protected, meaning that the applied voltage cannot be dissipated in the event of a fault. Therefore, the conductor elements (102, 102a, 102b) are provided to establish an electrical connection between the respective heating module (101a, 101b) and the electronics housing (104).According to the invention, at least one first heating module (101a) is electrically connected to the electronics housing (104) and consequently also to the vehicle's ground connection (105) by a first conductor element (102a), and a second heating module (101b) is electrically connected to the vehicle's ground connection (105) by a second conductor element (102b). It is understood that embodiments with more than two heating modules are also conceivable, wherein preferably the number of conductor elements corresponds to the number of heating modules.

[0039] Fig. Figure 2 shows a schematic cross-section through a heating module (101) for an electric heater (100), comprising a heating element (106), which in this embodiment is designed as a cuboid-shaped PTC block. The heating element (106) is electrically connected on two opposite sides to contact electrodes (107), which provide the voltage supply to the heating element. Electrical insulation from the tube (109), shown here as a flat tube, is provided by the attached insulation (108), shown here as ceramic insulating plates. Also shown are the heat-transferring elements (110), which are attached to the outside of the tube and are in heat-transferring contact with the fluid flowing around them.

[0040] Fig. Figure 3 shows a schematic cross-section of an embodiment of the electric heater (100). A heating module (101) is visible, which partially projects into the electronics interior (113) through an opening (115) in the electronics housing (104). The electronics interior is bounded by the electronics housing (104) and the electronics housing cover (114). The seal (103) ensures a fluid-tight closure of the opening (115) between the heating module (101) and the electronics housing (104). The heating module connections (111), which electrically connect the heating module (101) to a power electronics unit (112), are also visible. Elements for controlling and supplying power to the heating modules (101) are mounted on the power electronics unit (112), but these are not shown here. In the illustrated embodiment, the conductor element (102) according to the invention surrounds the heating module (101) on two sides.The contact tabs (116) of the conductor element (102) are visible, with the module contact tab (117) electrically connecting the heating module (101) to the conductor element (102) and the housing contact tab (118) electrically connecting the conductor element (102) to the electronics housing (104). Furthermore, the... Fig. 3 A cover element (119) is arranged in the electronics interior (113) and covers the heating module (101) from the electronics interior (113). The cover element (119) has recesses that allow an electrical connection between the heating module terminals (111) and the power electronics (112). The cover element (119) rests on a support surface (120) of the electronics housing (104), which can serve to support and / or fasten the cover element (119) within the electronics interior (113), for example, by gluing or screwing it in place. In the illustrated embodiment, the cover element (119) also has a support surface (121) for the power electronics (112), which can serve to support and / or fasten the power electronics (112) within the electronics interior (113), for example, by gluing or screwing it in place.To secure the conductor element (102) in its position and / or to ensure electrical contact, see . Fig. 3 also a spacer element (122), which in the illustrated embodiment is designed as part of the cover element (119), but can also be connected to the cover element (119) as a separate component.

[0041] Fig. Figures 4a to 4c schematically show different embodiments of the conductor element (102) which encloses a heating module (101) with a square cross-section, each viewed as a cross-section in the direction along the heating module. Fig. 4a The conductor element (102) is configured in an L-shape, with the module contact lugs (117) contacting the heating module (101) on two connected outer sides. Fig. 4b the conductor element (102) has a C or U shape and surrounds the heating module (101) on three outer sides, wherein the module contact tabs (117) electrically connect the heating module (101) to the conductor element (102) on these outer sides. Fig. Finally, section 4c describes a complete enclosure of the heating module (101) by the conductor element (102), which is shaped like an O. In the illustrated embodiment, four module contact lugs (117) are shown, each of which electrically connects one outer surface of the heating module (101) to the conductor element (102). However, embodiments are also conceivable in which more or fewer than the four illustrated module contact lugs (117) are provided, and which, for example, establish the electrical connection only on two opposite outer surfaces of the heating module (101). The arrangement of the housing contact lugs (118) – both in terms of number and arrangement relative to the conductor element (102) – is also only to be considered an exemplary embodiment, and the multitude of possible further variations cannot be exhaustively described here.

[0042] Fig. 5a and Fig. Figure 5b schematically shows the cross-section of a conductor element (102) and in particular the area of ​​the contact lugs (116) in the extended ( Fig. 5a) and in the built-in ( Fig. 5b) State, wherein in the illustrated embodiment the area around the module contact flag (117) is shown. In the installed state according to Fig. 5b the contact flag (116) is moved from a neutral position by installation in the electric heater similarly to a sheet metal spring ( Fig. 5a) bent or deflected by the angle α (123). The degree of deflection is provided by appropriate dimensioning of the contact flag (116) such that it is within the elastic range of the material. The deflection generates a restoring force or spring force F. F (124), which acts in the direction of the surface against which the contact flag (116) rests. In the exemplary embodiment in Fig. Figure 5b shows the module contact flag (117) in its installed state, which rests against the outer surface of a heating module (101), with the spring force F F (124) acts perpendicular to the outer surface of the heating module (101).

[0043] Fig. Figure 6 schematically shows a conductor element (102) which is attached to the cover element (119) by a retaining element (125). In the embodiment shown, the retaining element (125) has the form of a hook that is guided through an opening in the cover element (119) and forms a mechanical connection to the cover element (119) at its upper, hook-shaped end. Preferably, the conductor element (102) is attached to the cover element (119) by a retaining element (125) at at least two, and particularly preferably at four, points to ensure stable positioning. In addition to the hook shape of the retaining element (125) shown in the exemplary embodiment, other shapes are also possible, for example, a clamp, wedge, or shield shape.

[0044] Fig.Figure 7 shows a section of some components of an embodiment of an electric heater (100) in which six openings (113) are provided in the electronics housing (104) for six heating modules (101) – not shown. The six conductor elements (102) are O-shaped so that they completely enclose the heating modules (101) in their final state. Each conductor element (102) is equipped with four module contact tabs (117) and two housing contact tabs (118) to establish electrical contact with the respective component. Furthermore, each conductor element (102) has two retaining elements (125) which are attached to diagonally opposite sides of the conductor element (102). For clarity, the cover element (119) is shown offset to make the conductor elements (102) visible. Reference symbol list 100 Electric Heaters 101 Heating module 101a Heating module 1 101b Heating module 2 102 ladder element 102a Conductor element 1 102b Ladder element 2 103 Seal 104 electronic enclosures 105 Neutral conductor or ground connection of the vehicle 106 Heating element 107 Contact electrode 108 Insulation 109 pipe 110 Heat transfer element 111 Heating module connection 112 Power Electronics 113 Electronics Interior 114 Electronic housing cover 115 Opening in the electronics housing 116 Contact flag 117 Module contact flag 118 Housing contact tab 119 Cover element 120 Contact surface on the electronics housing for cover element 121 Contact surface on the cover element for power electronics 122 spacer element 123 Deflection angle α 124 Spring force F F 125 retaining element

Claims

[1] An electric heater (100) for a vehicle, comprising - at least two heating modules (101), wherein a heating module (101) comprises at least one heating element (106) arranged between two contact electrodes (107) and electrically insulated from a surrounding tube (109) by an insulation (108), wherein heat-transferring elements (110) are attached to the outer surface of the tube (109), - an electronic housing (104), wherein the at least two heating modules (101) project into the electronic housing (104) through at least one opening (115) and wherein the opening (115) in the electronic housing (104), through which a heating module (101) projects, is sealed by a seal (103), and - at least two conductor elements (102) arranged inside the electronic housing (104), characterized by , that - a first heating module (101a) through a first conductor element (102a) and - a second heating module (101b) is electrically connected to the electronic housing (104) by a second conductor element (102b). [2] Heater (100) according to claim 1 characterized by , that at least one of the at least two conductor elements (102) has at least one contact lug (116), wherein the contact lug (116) - is designed as a module contact flag (117) with which the conductor element (102) is electrically connected to a heating module (101) and / or - is designed as a housing contact tab (118) with which the conductor element (102) is electrically connected to the electronic housing (104). [3] Heater (100) according to claim 2 characterized by , that the contact flag (116) consists of at least one sheet metal spring which is tensioned in the installed state and thereby ensures an electrical contact with the adjacent component (101, 104). [4] Heater (100) according to claim 3 characterized by, that the vector of the spring force (124) of the tensed module contact flag (117) is predominantly perpendicular to the surface of the heating module (101) electrically connected to the conductor element (102). [5] Heater (100) according to any of the preceding claims characterized by , that at least one of the two conductor elements (102) is geometrically designed in such a way that it at least partially surrounds the heating module (101) to which it is electrically connected. [6] Heater (100) according to any of the preceding claims characterized by , that the at least two conductor elements (102) are connected to each other by an electrically non-conductive element. [7] Heater (100) according to one of the preceding claims, comprising a power electronics (112) and a cover element (119) which at least partially covers a heating module (101) projecting into the electronic housing (104) towards the power electronics (112). [8] Heater (100) according to claim 7 characterized by, that at least one of the two conductor elements (102) is mechanically connected to the cover element (119) via a retaining element (125). [9] Stoker (100) according to claim 7 characterized by , that the cover element (119) has at least one spacer element (122) which, in the installed state, is arranged between the cover element (119) and the conductor element (102). [10] A method for manufacturing an electric heater (100) comprising the following steps: - Providing at least two heating modules (101a, 101b), each comprising at least one heating element (106) arranged between two contact electrodes (107) and electrically insulated from a surrounding tube (109) by an insulation (108), wherein heat-transferring elements (110) are arranged on the outside of the tube, - Aligning at least two heating modules (101a, 101b) to an electronics housing (104), wherein the heating modules (101a, 101b) protrude at least partially through at least one opening (115) of the electronics housing (104), - Installing at least one seal (103) in the opening (115) between the electronics housing (104) and at least one of the two heating modules (101) which protrude through the opening (113), - Alignment and insertion of at least one first conductor element (102a) relative to the first heating module (101a) and one second conductor element (102b) relative to the second heating module (101b) such that the first heating module (101a) is electrically connected to the electronic housing (104) by the first conductor element (102a) and the second heating module (101b) is electrically connected to the electronic housing (104) by the second conductor element (102b).

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