Electric heating device, in particular for a motor vehicle

Abstract

The invention relates to a device (1) for electrically heating a liquid, comprising a heating body (11) and a housing (3), the housing (3) at least partially defining a chamber (30) for the circulation of the liquid, the heating body (11) comprising at least one electric heating element (7, 9) extending in the chamber (30) and attached to an inner wall of the device so as to form a first mechanical connection, the inner wall at least partially defining the chamber (30) for the circulation of the liquid. According to the invention, the electric heating device (1) comprises at least one mechanical connection element (21) arranged in the chamber (30), the mechanical connection element mechanically connecting the at least one electric heating element (7, 9) to an inner surface of the housing (3) extending opposite the heating body (11), thereby forming a second mechanical connection separate from the first mechanical connection.

Description

TECHNICAL FIELD

[0001] The field of the invention is that of electrical devices for heating and circulating a fluid, in particular a liquid, such as for example the equipment for heating, ventilation and / or air conditioning of the interior of a motor vehicle. More particularly, the invention relates to an electrical heating device for such equipment in an electric or hybrid motor vehicle equipped with a high-voltage electrical power supply network. BACKGROUND

[0002] The air used for the thermal treatment of the interior of a motor vehicle having a thermal engine is heated by heat exchange, by heat exchange between an air flow and a heat transfer fluid, such as a liquid. In the case of hybrid or electric vehicles, electrical heating devices are known which constitute a thermal energy source and in which an electric current flows to raise the temperature of a heating body extending longitudinally inside a housing of the heating device. The liquid to be heated then passes through the electrical heating device and comes into contact with the heating body. Heat energy exchange then takes place between the heating body and the liquid used to heat the interior of the vehicle, thereby heating the interior of the vehicle.

[0003] The heating body generally comprises at least one electrical heating element, such as one or more heating resistors. In order to obtain a heating power sufficient to carry out the desired operation, it is possible to increase the number of electrical heating elements in a single electrical heating device.

[0004] Furthermore, the housing can accommodate an electrical circuit carrying the electrical elements, in particular the electrical terminals of each electrical heating element, which can be connected to the electrical power supply system. It is therefore necessary to provide a sealed separation between this electrical circuit and the circuit of the liquid to be heated.

[0005] According to a known solution, the electrical heating device comprises a housing inside which a liquid circulation chamber is at least partially delimited. The electrical heating device comprises an internal wall delimiting at least partially this chamber, which carries one or more electrical heating elements. Electrical terminals can pass through this wall, which then give access to a cavity accommodating an electrical circuit. It is necessary to ensure the sealing at this wall.

[0006] When there are a plurality of electrical heating elements, it is preferable to fix all the electrical heating elements on the same wall, in order to concentrate the sealing measures on this wall. The electrical heating elements are thus mounted in a cantilevered manner in the housing.

[0007] In use, the electrical heating device mounted on a motor vehicle, for example in practice mounted on the engine, moves or vibrates and the various components of the electrical heating device can come into collision, in particular the electrical heating elements, such as the heating resistors of the heating body, which can come into collision with each other and with the inside of the housing. This can generate noise and can also cause the components in contact to wear more quickly. SUMMARY

[0008] The present invention aims to at least partially overcome the problems found in the prior art by proposing an electric heating device which can limit the noise generated by vibrations, in particular when used in a motor vehicle.

[0009] To this end, the subject of the present invention is an electric heating device for heating a liquid, in particular for a motor vehicle, comprising a heating body and a housing at least partially delimiting a liquid circulation chamber, the heating body comprising at least one electric heating element which extends within the liquid circulation chamber and is fixed to an internal wall of said device at least partially delimiting the liquid circulation chamber to form a first mechanical connection. According to the invention, the electric heating device comprises at least one mechanical connection element arranged within the liquid circulation chamber, which mechanically connects said at least one electric heating element and an internal surface of the housing which extends facing the heating body, thereby forming a second mechanical connection distinct from the first mechanical connection.

[0010] The additional mechanical connection provides a complement to the first mechanical connection, thereby limiting the cantilevering of the electric heating element(s) within the housing.

[0011] This additional mechanical connection can absorb the tolerance ranges between the various components and limit the noise or vibrations generated, in particular during use in a motor vehicle.

[0012] The additional mechanical connection also forms a thermal bridge between the electric heating element(s) and the housing, which makes it possible to more accurately measure the temperature of the electric heating element(s), even in the absence of liquid in the chamber. This liquid is for example a glycol water.

[0013] The electric heating device can also have one or more of the following characteristics, considered individually or in combination.

[0014] Said at least one electric heating element can take the form of a heating resistor.

[0015] According to one example, the heating body comprises a base fixed to the housing, such that the housing and the base at least partially delimit the liquid circulation chamber.

[0016] The first mechanical connection is for example located between said at least one electric heating element and the base. In this case, the internal wall which carries said at least one electric heating element is defined by the base. This is the base wall on the side facing the liquid circulation chamber.

[0017] Said at least one electric heating element comprises two terminal portions provided with electrical terminals, which are for example fixed to the base.

[0018] According to one aspect of the invention, the heating body comprises at least two electric heating elements which extend within the liquid circulation chamber, all of the electric heating elements being for example fixed to the base.

[0019] Preferably, the second mechanical connection is ensured by at least three contacts in contact with the or each electric heating element.

[0020] The electric heating element or at least one electric heating element can at least partly have a helical shape.

[0021] The at least one mechanical connection element can be arranged between the inner surface of the housing and at least one winding of the electric heating element or at least one electric heating element.

[0022] According to one example, the electric heating element or at least one electric heating element comprises a first terminal portion followed by an intermediate part, for example a winding portion, followed by a straight second terminal portion, the first terminal portion and the second terminal portion extending between the intermediate part, for example the winding portion, and the base.

[0023] The at least one mechanical connection element is for example arranged in the liquid flow-through chamber opposite the base.

[0024] According to one exemplary embodiment, the electric heating element or at least one electric heating element extends longitudinally in the liquid flow-through chamber.

[0025] The at least one mechanical connection element can be arranged in the liquid flow-through chamber, mechanically connecting the inner surface of the housing to a longitudinal end of the electric heating element or at least one electric heating element.

[0026] According to one embodiment, the heating body comprises at least two electric heating elements arranged in an axial extension direction of each other. The electric heating elements arranged in an axial extension direction of each other are for example wound around a common axis.

[0027] The at least one mechanical connection element can be axially arranged between the two electric heating elements.

[0028] According to one embodiment, the heating body comprises at least two concentric electric heating elements, one placed around the other. More specifically, at least one outer electric heating element is placed around at least one inner electric heating element. The winding axes of the electric heating elements can coincide.

[0029] The heating body comprises for example at least a first electric heating element defined by a first diameter and a second electric heating element defined by a second diameter smaller than the first diameter, such that the first electric heating element is placed around the second electric heating element.

[0030] The first and second electric heating elements are for example at least partly helical in shape.

[0031] The at least one mechanical connection element can be at least partly arranged between the concentric electric heating elements.

[0032] According to an aspect of the application, the at least one mechanical connection element is in the form of an intermediate part arranged between the inner surface of the housing and the heating body. The intermediate part is thus an additional part added to the electric heating device.

[0033] According to an alternative, the plurality of contacts can be formed by a single intermediate part.

[0034] According to another alternative, a plurality of intermediate parts is provided to ensure that each part has at least one contact.

[0035] The intermediate part can be made of a thermally conductive material, preferably a metal, to form a thermal bridge.

[0036] Such a metal can withstand the operating temperature of an electric heating element, such as a heating resistor, with which the at least one mechanical connection element is in mechanical contact.

[0037] Advantageously, the intermediate part has at least partly elasticity and flexibility. This provides the intermediate part with a spring effect, making it possible to compensate for a range of tolerances, deviations or dimensional errors of the electric heating device.

[0038] According to an aspect of the application, the intermediate part comprises a core part arranged transversely towards the longitudinal end of the electric heating element or one of the electric heating elements, and a predetermined number of contact tabs extending from the core part in the direction of the heating body and arranged in contact with the electric heating element.

[0039] The intermediate part comprises at least three contact tabs.

[0040] The contact tabs can extend in the direction of the heating body, be arranged in contact with the at least one electric heating element, and have the same or different extension.

[0041] The contact tabs can be of any suitable shape to ensure contact with the electric heating element or one of the electric heating elements. By way of example only, the contact tabs can be straight, curved, or even have a concave surface. The contact tabs can be inclined with respect to the longitudinal axis of the electric heating element, for example forming an angle of about 30° to 45° prior to contact. The contact tabs can be alternately inclined in different directions.

[0042] The inclination or curvature of the contact tabs provides flexibility for assembly, allowing the contact tabs to deform when the electric heating element or one of the electric heating elements rests on the intermediate part.

[0043] According to an embodiment, the core part of the intermediate part is arranged to rest on the inner surface of the housing opposite the base. The core part is held in place by pressing the intermediate part between the electric heating element and the inner surface of the housing opposite the base.

[0044] According to one variant, at least some of the contact tabs of the intermediate part can be in contact with the inner surface of the outer shell. For example, tabs in contact with the inner surface of the outer shell and in contact with the electric heating element can be provided alternately.

[0045] Alternatively, each contact tab arranged between the inner surface of the outer shell and the electric heating element can be in contact with both.

[0046] The heating body is generally hollow, such as cylindrical. In particular, the at least one electric heating element defines a generally hollow shape, such as a cylinder.

[0047] According to one embodiment, the core of the intermediate part is generally annular, with an inner diameter smaller than an outer diameter. A first set of tabs, called inner tabs, can extend from the inside of the annular shape towards the inside of the heating body, that is to say, towards the inside of the generally hollow shape of the heating body, while a second set of tabs, called outer tabs, can extend from the outside of the annular shape towards the outside of the heating body, that is to say, towards the outside of the generally hollow shape of the heating body.

[0048] For example, when the inner electric heating element is hollow, the inner tabs extend towards the inside. When the outer electric heating element defines a generally hollow shape, the outer tabs extend towards the outside of the outer electric heating element, for example.

[0049] According to another embodiment, the core has the general shape of a disc.

[0050] In a configuration of the heating body comprising at least two concentric electric heating elements, one being placed around the other, at least some of the contact tabs of the intermediate part can be arranged between the concentric electric heating elements.

[0051] According to one embodiment, all of the contact tabs of the intermediate part can be arranged between the concentric electric heating elements.

[0052] In a configuration of the intermediate part having contact tabs inclined in different directions, a first contact tab can be arranged to bear against the outer electric heating element, an alternate second contact tab can be arranged to bear against the inner electric heating element.

[0053] According to another embodiment, the intermediate part is made in the form of a clip comprising a head arranged to bear against the outer electric heating element, and comprising at least a first tab and a second tab extending from the head. The first tab is arranged to bear against the inner electric heating element, the second tab is arranged to bear against the inner surface of the outer shell.

[0054] The head is for example circular, complementary to the tubular shape of the electric heating element.

[0055] The first tab can be straight.

[0056] The second tab can be straight. It is advantageously dome-shaped or convex, and its convexity faces the inner surface of the housing. The dome shape avoids damaging the inner surface of the housing.

[0057] The application also relates to a device for heating and / or ventilating and / or air-conditioning an air flow, having an electric heating device as described above. BRIEF DESCRIPTION OF DRAWINGS

[0058] Other advantages and features of the application will become more apparent from the following description, given by way of illustrative and non-limiting example, and from the annexed drawings.

[0059] Figure 1 An electric heating device according to the application is shown;

[0060] Figure 2 A heating body is shown Figure 1 The heating body of the electric heating device shown comprises two electric heating elements;

[0061] Figure 3 A heating body comprising three electric heating elements is shown;

[0062] Figure 4 A mechanical connection element according to a first embodiment is shown assembled on Figure 2 A mechanical connection element according to a first embodiment is shown assembled on

[0063] Figure 5 A cross-sectional view of an electric heating device comprising Figure 4 a heating body and a mechanical connection element in

[0064] Figure 6 A first view of Figure 4 and Figure 5 a mechanical connection element;

[0065] Figure 7 A second view of Figure 4 and Figure 5 a mechanical connection element;

[0066] Figure 8 A cross-sectional view of an electric heating device according to a second embodiment comprising a heating body and a mechanical connection element;

[0067] Figure 9 A cross-sectional view of an electric heating device according to a third embodiment comprising Figure 3 a heating body and two mechanical connection elements in

[0068] Figure 10 A perspective view of a mechanical connection element according to a third embodiment;

[0069] Figure 11 A perspective view of a mechanical connection element according to a fourth embodiment;

[0070] Figure 12 Fig. 1 shows a first example of an arrangement of mechanical connection elements in a housing of an electric heating device comprising one electric heating element; Figure 11

[0071] Figure 13 Fig. 2 shows a second example of an arrangement of mechanical connection elements in a housing of an electric heating device comprising two electric heating elements; Figure 11

[0072] Fig. 3 shows a mechanical connection element according to a fifth embodiment assembled on a heating body; Figure 14 Figure 2 Fig. 4 shows a perspective view of a mechanical connection element according to a fourth embodiment;

[0073] Figure 15 Figure 14 Fig. 5 shows a perspective view of a variant of the mechanical connection element shown in Fig. 4;

[0074] Figure 16 Fig. 6 shows a perspective view of a mechanical connection element according to a sixth embodiment; Figure 15

[0075] Figure 17 Fig. 7 shows a mechanical connection element according to a seventh embodiment assembled on a heating body;

[0076] Figure 18 Fig. 8 shows a mechanical connection element according to an eighth embodiment assembled on a heating body; Figure 2 Figure 17

[0077] In these figures, identical elements have identical reference numerals. DETAILED DESCRIPTION

[0078] The following examples are illustrative. Although the specification can refer to "an" or "one" embodiment, this does not necessarily limit the disclosure to a single embodiment, but rather, the term "an" or "one" embodiment means at least one or more embodiments. The specification can refer to several examples, embodiments, or alternatives as "another" embodiment, which does not necessarily mean any and all embodiments.

[0079] In this specification, certain elements can be indexed, for example, a first element or a second element. In this case, this is merely an index for distinguishing and indicating similar but not identical elements. Such an index does not mean that one element is superior to another element, and such a designation can be easily interchanged without departing from the scope of the specification. Such an index also does not mean a chronological order.

[0080] Reference is made to Figure 1 ​​​​​​The present invention relates to an electric heating device 1, in particular for a motor vehicle, such as an electric or hybrid motor vehicle. The electric heating device 1 is in particular intended to interact with a device for heating and / or ventilating and / or air conditioning a flow of air for such a motor vehicle. This is an electric heating device 1 for heating a fluid, in particular a liquid such as glycol water.

[0081] The electric heating device 1 comprises a housing 3. The housing 3 can have a substantially cylindrical or conical shape. Alternatively, it can have a substantially parallelepiped shape.

[0082] The electric heating device 1 comprises a liquid flow-through chamber 30 at least partially delimited by the housing 3.

[0083] The housing 3 extends longitudinally, for example along an extension axis of the electric heating device 1, referred to as longitudinal axis A. The housing 3 is delimited by a first longitudinal end 31 and a second longitudinal end 33. For example, as illustrated, the longitudinal ends 31 and 33 extend in a plane parallel to each other and orthogonal to the longitudinal axis A.

[0084] According to the particular embodiment illustrated, the electric heating device 1 comprises a base 5 on which the housing 3 is fixed, thereby delimiting the chamber 30 for the liquid flow-through within the housing 3. The base 5 is arranged at the first longitudinal end 31 of the housing 3. The liquid flow-through chamber 30 is centred on the longitudinal axis A. The liquid flow-through chamber 30 is defined as substantially cylindrical or conical. Other alternatives can also be considered, for example a parallelepiped shape.

[0085] The base 5 can also form a partition between the liquid flow-through chamber 30 and a cavity (not shown) of the electric heating device 1, for example the housing 3, in which, for example, an electrical circuit can be installed. Figure 1

[0086] The electric heating device 1 also comprises an inner wall at least partially delimiting the flow-through chamber 30, which carries one or more electric heating elements 7, 9, such as heating resistors. This inner wall forms a support for these electric heating elements 7, 9. This inner wall can or can not be defined by the housing 3.

[0087] In particular, this inner wall can be defined by the base 5. In this case, the base 5 carries one or more electric heating elements 7, 9, such as heating resistors. The remainder of the description relates to this particular embodiment of the inner wall defined by such a base 5. Of course, the invention is not limited to this particular example and the remainder of the description can be applied to another inner wall of the electric heating device 1 not defined by such a base.

[0088] ​One or more electric heating elements 7 and 9 extend within the liquid flow-through chamber 30. In operation, a liquid to be heated can flow through this chamber 30 and, upon contact with the one or more electric heating elements 7, 9, increase in temperature by exchanging heat therewith. The heated liquid can then be discharged from the electric heating device 1 so as to be sent to other components of the motor vehicle.

[0089] The one or more electric heating elements 7, 9 are fixed to the base 5, thereby forming a first mechanical connection between the electric heating elements 7, 9 and the base 5. To this end, the one or more electric heating elements 7, 9 are inserted and fixed in a sealed manner in a hole (not visible) made in the base 5, so that the liquid flowing through the flow-through chamber does not leak. The one or more electric heating elements 7, 9 are fixed to the base 5, for example by welding.

[0090] The electric heating elements 7 and 9 are respectively provided with electric terminals 71 and 91. The electric terminals 71, 91 extend, for example, in a direction substantially parallel to the longitudinal axis A

[0091] The electric terminals 71, 91 extend from the side of the base 5 opposite the liquid flow-through chamber 30, so as to be connected to an electrical power source, for example by means of an electrical circuit.

[0092] The base 5 and the one or more electric heating elements 7 and 9 form an assembly, referred to as a heating body 11, which can be seen more clearly in Figure 2 In the example shown, the arrangement of the base 5 and the one or more electric heating elements 7, 9 defines a substantially cylindrical shape of the heating body 11. The latter thus has a first longitudinal end formed by the base 5 and a second longitudinal end opposite the base 5.

[0093] Figure 2 An embodiment of the heating body 11 is particularly shown, comprising a first electric heating element 7 and a second electric heating element 9. Of course, other configurations can be envisaged, such as a single electric heating element or more than two electric heating elements. The Figure 2 The relative arrangement of the two electric heating elements 7, 9 is shown.

[0094] In the embodiment shown, the two electric heating elements 7, 9 extend longitudinally within the liquid flow-through chamber 30, the length or height of the extension being substantially the same as Figure 2 the direction shown.

[0095] The at least one electric heating element 7, 9 can be of a substantially hollow shape, such as a cylinder. The electric heating element 7, 9 is for example substantially tubular and can be arranged, for example, at least partially wound, so as to define a substantially hollow shape, such as a cylinder. In particular, the at least one electric heating element 7, 9 has at least partially a helical shape.

[0096] According to the particular embodiment shown, the electric heating elements 7, 9 comprise a first terminal portion 13 fixed to the base 5, extending to an intermediate part, such as a helically shaped winding portion 15, which extends along the longitudinal axis A and which terminates in a second terminal portion 17. The first terminal portion 13 and the second terminal portion 17 extend between the winding portion 15 and the base 5 of the respective electric heating element 7, 9. The terminal portions 13, 17 are each equipped with one of the electrical terminals 71, 91 at their end portions.

[0097] Furthermore, in the particular example shown, the second terminal portion 17 of the electric heating elements 7, 9 extends rectilinearly in a central region within the winding portion 15. The second terminal portion 17 makes it possible to connect the distal end of the winding portion 15 with respect to the base 5 to said base 5.

[0098] The two electric heating elements 7, 9 can be concentric, one being placed around the other. In the example shown, the first electric heating element 7 is defined by a first diameter dl, the second electric heating element 9 being defined by a second diameter d2 which is less than the first diameter dl, so that the first electric heating element 7 is placed around the second electric heating element 9. In this configuration, the first electric heating element 7 thus forms an outer element, while the second electric heating element 9 forms an inner element.

[0099] In particular, in the case where the electric heating elements 7, 9 are at least partially helically shaped, the winding portion 15 of the electric heating elements 7, 9 is wound on the same winding axis, which coincides with the longitudinal axis A

[0100] The heating body 11 is advantageously arranged in the housing 3 so that, in a plane orthogonal to the longitudinal axis A, a point on the outer surface of the winding portion 15 of at least one of the electric heating elements 7, 9 is equidistant or substantially equidistant from the inner surface of the housing 3.

[0101] Other configurations are also possible. For example, two or more electric heating elements can be arranged in axial alignment. One or more electric heating elements can or can not be placed around or inside these aligned electric heating elements.

[0102] Figure 3 An example of a variant embodiment is shown. In this example, the heating body 11 comprises three electric heating elements 7, 8, 9, each provided with a respective electrical terminal 71, 81, 91 at its end portion. A first electric heating element 7 defined by a first diameter dl, a second electric heating element 9 defined by a second diameter d2, and a third electric heating element 8 defined by a third diameter d3. The first diameter dl is greater than the second diameter d2 and the third diameter d3. The second and third diameters d2 and d3 can be equal.

[0103] The various electric heating elements 7, 8, 9 are arranged so that the first electric heating element 7 is placed around the second and third electric heating elements 8, 9. In particular, as shown in Figure 3 the third electric heating element 8 is arranged in the axial extension and at the end of the second electric heating element 9, both electric heating elements 8 and 9 having a common winding axis which coincides with the winding axis of the first electric heating element 7 and also with the longitudinal axis A.

[0104] According to another variant, not shown, the second and third electric heating elements 9, 8 can be placed around the first electric heating element, in which case the diameter of the first electric heating element is smaller.

[0105] With reference to Figure 4 and Figure 5 , a seal 19, for example an annular seal, is advantageously arranged at the bottom of the heating body 11, in the receiving groove between the base 5 and the outer shell 3, in the assembled condition of the electric heating device 1, to seal the liquid circulation chamber 30.

[0106] The electric heating device 1 also comprises at least one mechanical connection element 21 arranged in the liquid circulation chamber 30, which mechanically connects one or more electric heating elements 7, 9 and the inner surface of the outer shell 3 extending facing the heating body 11, to form a second mechanical connection distinct from the first mechanical connection. Thus, a mechanical connection is added between the inner surface of the chamber 30 and one or more electric heating elements 7, 9.

[0107] Figures 4 to 18 Various embodiments of the mechanical connection element 21 are shown. The electric heating device 1 can comprise a single mechanical connection element 21, or, on the contrary, several mechanical connection elements 21.

[0108] In general, when a plurality of electric heating elements is provided, the second mechanical connection is preferably ensured by at least three contacts with one or at least one of the electric heating elements 7, 8, 9. In particular, the second mechanical connection is ensured by at least three contacts with each electric heating element 7, 8, 9.

[0109] When the electric heating elements 7, 8, 9 are at least partially in the above-mentioned spiral shape, the mechanical connection element 21 is in particular intended to mechanically connect the inner surface of the outer shell 3 to at least one winding of the electric heating elements 7, 8, 9.

[0110] Said mechanical connection element or at least one of the mechanical connection elements 21 can be arranged in the liquid circulation chamber 30, mechanically connecting the inner surface of the outer shell 3 to the longitudinal end of one or more electric heating elements 7, 8, 9. In particular, it can be arranged transversely facing the longitudinal end of at least one electric heating element 7, 8, 9.

[0111] In particular, the or at least one mechanical connection element 21 can be arranged opposite the base 5.

[0112] When the heating body 11 comprises at least two independent electric heating elements 7, 8, 9, the or at least one mechanical connection element 21 can be arranged between the two independent elements 7, 8, 9, at a distance so that they do not come into contact with each other, nor do they overlap. Preferably, the individual electric heating elements 7, 8, 9 and the or at least one mechanical connection element 21 are arranged so as to limit or even prevent any direct contact between the electric heating elements 7, 8, 9, either at their own terminal portions 13 and 17 or at their winding portions 15.

[0113] When the heating body 11 comprises at least two concentric electric heating elements 7, 8 or 9 and one is placed around the other, the mechanical connection element 21 can be arranged between the two electric heating elements, in a plane orthogonal to the longitudinal axis A.

[0114] When the heating body 11 comprises at least two electric heating elements 8, 9 arranged in the axial extension of each other, the mechanical connection element 21 can be arranged axially between the two electric heating elements 8, 9.

[0115] According to Figures 4 to 16 According to the described embodiment, the mechanical connection element 21 takes the form of an intermediate part 23 or 25 or 26 or 27 or 28 or 29 arranged between the inner surface of the casing 3 and the heating body 11. The or at least one mechanical connection element 21 can be arranged between the heating body 11 and the end or side inner surface of the casing 3.

[0116] Thus, the second mechanical connection is an indirect connection between the casing 3 and the one or more electric heating elements 7, 8, 9.

[0117] This intermediate part 23, 25, 26, 27 or 28, 29 is made of a thermally conductive material so as to form a thermal bridge between the electric heating element 7, 9 and the casing 3. This facilitates the temperature measurement of the electric heating element even when there is no liquid in the flow-through chamber 30.

[0118] The material is chosen to withstand a large amount of flow-through. It is in particular a metal configured to withstand the operating temperature of the electric heating element in mechanical contact with the mechanical connection element.

[0119] Such intermediate parts 23, 25, 26, 27 or 28, 29 have at least partially an elasticity and flexibility, making it possible to compensate for the tolerance range of the electric heating device. More generally, the intermediate parts 23, 25, 26, 27 or 28, 29 are shaped to obtain a balance between rigidity and flexibility, to guarantee mechanical contact with the electric heating elements 7, 8, 9 in the flow-through chamber 30, without crushing them. The intermediate parts 23, 25, 26, 27 or 28, 29 can be configured to withstand a retention force, which can vary in the range of 10 N to 50 N, by way of example only.

[0120] According to any of the embodiments described below, the shape of the intermediate part 23, 25, 26, 27 or 28, 29 is complementary to the element with which it is about to interact.

[0121] First embodiment

[0122] Figures 4 to 7 A first embodiment is shown, according to which the electric heating device 1 comprises the two electric heating elements 7, 9 described with reference to Figure 2 and an intermediate part 23 configured to ensure a plurality of contacts with at least one or each electric heating element 7, 9.

[0123] This intermediate part 23 comprises a core 231 arranged transversely facing the longitudinal end of the heating body 11. This core 231 is advantageously centred on the longitudinal axis A.

[0124] The intermediate part 23 also comprises a predetermined number of contact tabs 233 extending from the core 231. Preferably, at least three or a multiple of three contact tabs 233 are provided.

[0125] For example, the core 231 of the intermediate part is arranged to abut against the inner surface of the housing 3 at the second longitudinal end 33 of the housing 3, opposite the base 5. According to the example of a cylindrical housing 3 shown, the longitudinal end 33 of the housing 3 is an end face of circular cross-section.

[0126] When the electric heating elements 7, 9 are housed in the housing 3, the intermediate part remains pressed against the inner surface of the housing 3 by the stresses exerted by the electric heating elements 7, 9.

[0127] The shape of the core 231 can be complementary to the overall shape of the heating body 11, and in particular to the shape of the longitudinal end of the heating body 11 with which it is facing. The core 231 can also have a shape complementary to the shape of the inner surface of the housing 3 against which it is pressed.

[0128] In the example shown, the core 231 has the general shape of a disc. The diameter of the disc can be close to, or not close to, or correspond to the diameter of one of the electric heating elements.

[0129] The arrangement of the contact tabs 233 is related to the shape of the heating body 11, in particular to the longitudinal ends of the heating body 11 interacting with the intermediate part. According to the example of a substantially cylindrical heating body 11 shown, the contact tabs 233 are arranged in a circular manner. They are advantageously regularly distributed 360°.

[0130] The contact tabs 233 can be of any suitable shape to ensure contact with one or more of the electric heating elements 7, 9. In the example shown, the contact tabs 233 are straight. They extend longitudinally from the core 231 along an axis parallel or substantially parallel to the longitudinal axis A. According to this first embodiment, all the tabs 233 extend in the same direction relative to the longitudinal axis A, they all extend here parallel to the longitudinal axis A. The tabs 233 all extend from the same circumference of the core 231.

[0131] According to the first embodiment, all the contact tabs 233 can be in contact with at least one of the electric heating elements 7, 9, either inside or outside this electric heating element 7, 9.

[0132] Furthermore, the length of the contact tabs 233 is calculated to ensure at least three points of contact with at least one of the electric heating elements 7, 9. In particular, as shown in Figure 4 and 5 at least one of the contact tabs 233 is shaped to be in contact with each of the two electric heating elements 7, 9.

[0133] The contact tabs 233 extend from the peripheral edge of the core 231. They extend in the direction of the heating body 11, more precisely in the direction of the electric heating elements 7, 9. In particular, according to this first embodiment, the contact tabs 233 are arranged between the two electric heating elements 7 and 9, respectively. This ensures that a predetermined distance is maintained between the two electric heating elements 7, 9.

[0134] The contact tabs 233 can have flexibility to allow the contact tabs 233 to deform, thus ensuring that they are located between the two concentric electric heating elements 7, 9.

[0135] For example, the contact tabs 233 can be at least partially curved or inclined relative to the longitudinal axis A. This shape facilitates the deformation of the contact tabs when the intermediate part 23 and the heating body are inserted into the housing 3, thus ensuring mechanical contact between the two.

[0136] The above description relates to a heating body 11 comprising two electric heating elements 7, 9. Alternatively, the heating body 11 can comprise three electric heating elements 7, 8, 9, as referred to in Figure 3Said, and in this case, the intermediate part 23 is arranged to ensure several contacts with the first and third electric heating elements 7 and 8. Alternatively or additionally, such an intermediate part 23 can also be provided between two electric elements 8, 9 which are located in the axial extension direction of each other.

[0137] Second embodiment

[0138] Figure 8 A second embodiment of the intermediate part 25 forming the mechanical connection element 21 is shown. In the following only the differences to the first embodiment are detailed.

[0139] The intermediate part 25 comprises a core 251 from which a plurality of tabs 253, 255 extend, at least some of which 255 are in contact with the inner surface of the housing 3.

[0140] The core 251 can be similar or dissimilar to the core 231 described with reference to the first embodiment. Figures 4 to 7 The core 251 can have the shape of a disc or of a ring with a central hole.

[0141] Similar to the first embodiment, the core 251 can be pressed against the inner surface of one of the longitudinal ends of the housing 3, in this case the second longitudinal end 33.

[0142] The intermediate part 25 can comprise at least one first tab, referred to as inner tab 253, and at least one second tab, referred to as outer tab 255. Preferably, the intermediate part 25 comprises at least three inner tabs 253 and at least three outer tabs 255. The inner tabs 253 extend from the core 251 towards the interior of the heating body 11, that is to say, towards the interior of the generally hollow shape of the heating body 11, in particular towards the interior of the generally hollow shape of the second electric heating element 9 in the example shown. The outer tabs 255 extend from the core 251 towards the exterior of the heating body 11, in particular towards the exterior of the first electric heating element 7 placed around the second electric heating element 9.

[0143] The outer tabs 255 can be shaped to ensure mechanical contact with the inner surface of the housing 3; this is in particular the lateral surface of the housing 3. The outer tabs 255 can be shaped to also ensure mechanical contact with an electric heating element, in this example the first electric heating element 7. In this example, all contact tabs arranged between the inner surface of the housing 3 and the first electric heating element 7, here the outer tabs 255, are arranged in contact with both. Alternatively, it can be provided that the outer tabs are in contact with the inner surface of the housing and the electric heating element 7 alternately.

[0144] As mentioned before, the contact tabs 253, 255 can be straight. The outer tabs 255 can extend from the peripheral edge of the core 251. As for the inner tabs 253, they can extend from another region of the core 251, for example a more central region. In particular, according to the example shown, the inner tabs 253 and 255 extend from different regions, more precisely in this example from different circumferences. As mentioned above, the inner tabs 253 extend from the core 251 towards the interior of the substantially hollow shape of the heating body 11, that is to say, in the example shown, towards the interior of the substantially hollow shape of the second electric heating element 9. They abut against the second electric heating element 9 from the interior.

[0145] Similarly to the first embodiment, all the outer tabs 255 extend in the same direction relative to the longitudinal axis A and all extend parallel to the longitudinal axis A. The outer tabs 255 all extend from the same circumference of the core 231.

[0146] Likewise, all the inner tabs 253 extend in the same direction relative to the longitudinal axis A and all extend parallel to the longitudinal axis A. The inner tabs 253 all extend from the same circumference of the core 231.

[0147] Furthermore, according to the example shown, all the tabs, including the inner tabs 253 and the outer tabs 255, are oriented in the same way.

[0148] In the example shown, one longitudinal end of the heating body 11 is provided with one separate intermediate part 25. According to the variant of the heating body 11 described above with reference to Figure 3 the first embodiment, having at least two electric heating elements located in axial extension of each other, for example 8 and 9, it is conceivable to provide between the two electric heating elements 8, 9 axially another intermediate part 25 described above with reference to the second embodiment. In this case, this other intermediate part 25 will only be held against the inner side surface of the housing 3. It is also conceivable to arrange such an intermediate part 25 only between two electric heating elements located in axial extension of each other, instead of at an end of the heating body 11. Figure 8

[0149] Third embodiment

[0150] Figure 9 And 10 A third embodiment of the intermediate part 26 forming the mechanical connection element 21 is shown. Below only the differences to the second embodiment are detailed.

[0151] ​According to a third embodiment, the intermediate parts 26 comprise contact tabs 263, 265 extending from the core 261, at least some of the tabs 265 being curved. In the assembled state of the electric heating device 1, the curved contact tabs 265 extend radially, for example from the core 261, in the direction of the inner surface of the housing 3. These contact tabs 265 can then perform a half-turn or even form a bend, for example, giving them a curved shape.

[0152] When the intermediate parts 26 are fitted in the liquid flow-through chamber 30, the curved contact tabs 265 can deform to be positioned correctly and to ensure the required mechanical contact. According to a particular non-limiting example, the heating body 11 can be assembled with at least one such intermediate part 26. When the assembly is inserted into the liquid flow-through chamber 30, the contact tabs 265 of the intermediate part 26 can deform due to the stresses exerted by the inner surface of the housing 3 and the electric heating elements 7, 8, 9.

[0153] The core 261 is, for example, substantially annular, defined by an inner ring of inner diameter di and an outer ring of outer diameter de. The inner diameter di is less than the outer diameter de.

[0154] Figure 9 A configuration of a heating body with three electric heating elements 7, 8, 9 is shown, as described above with reference to Figure 3 . The first intermediate part 26 is arranged so that its core 261 faces, in particular is in contact with, a longitudinal end of the heating body 11, while the second intermediate part 26 is arranged axially between the second electric heating element 8 and the third electric heating element 9. This second intermediate part 26 is arranged so that its core 261, on one side, faces and is in contact with a longitudinal end of the wound portion 15 of the second electric heating element 9, and on the other side, faces and is in contact with a longitudinal end of the wound portion 15 of the third electric heating element 8, more precisely, on one side and on the other side, faces and is in contact with the ends of the wound portions 15 of these electric heating elements 8, 9. In particular, the second intermediate part 26 is in contact with the ends of the second electric heating element 8 or of the third electric heating element 9.

[0155] In the example shown in Figure 9 and Figure 10 , the intermediate parts 26 comprise a first set of tabs, called internal tabs 263, and a second set of tabs, called external tabs 265.

[0156] The internal tabs 263 extend from the inside of the annular core 261, i.e. from the inner ring towards the inside of the substantially hollow shape of the heating body 11. In the example shown, these internal tabs 263 are straight or substantially straight.

[0157] According to Figure 9In the configuration with the heating body 11 having three electric heating elements 7, 8, 9, the inner tabs 263 of the first intermediate part 26 are arranged at the longitudinal ends of the heating body 11, extending towards the substantially hollow interior of the third electric heating element 8. As for the inner tabs 263 of the second intermediate part 26 arranged between the second and third electric heating elements 9, 8, these tabs extend towards the substantially hollow interior of the second electric heating element 9.

[0158] The outer tabs 265 of the intermediate parts 26 extend from the outside of the annular core 261, i.e. from the outer ring, towards the outside of the heating body 11. In the example shown, the outer tabs 265 extend towards the outside of the first electric heating element 7, which is placed around the other two electric heating elements 8, 9. In the example shown, these outer tabs 265 are curved contact tabs as defined above.

[0159] Furthermore, Figure 9 The cavity 4 in the electric heating device 1 is shown, which is separated from the liquid flow chamber 30 by the base 5, into which the respective electrical terminals 71, 81, 91 of the electric heating elements 7, 8, 9 open, for example a circuit can be installed in the cavity 4.

[0160] The above description relates to a heating body 11 comprising three electric heating elements 7, 8, 9 and two intermediate parts 26. As a variant, only one of these intermediate parts 26 can be provided at the end of or between two electric heating elements 8, 9, which are located in the axial extension of each other. The heating body 11 can also only comprise two concentric electric heating elements 7, 9, as described with reference to Figure 2 In this case, a single intermediate part 26 can be arranged with its core 261 facing the longitudinal end of the heating body 11, thereby ensuring several contacts with both electric heating elements 7 and 9.

[0161] Fourth embodiment

[0162] Figure 11 A fourth embodiment of the intermediate part 27 forming the mechanical connection element 21 is shown. As mentioned before, only the differences with the first embodiment will be detailed below. Figure 12 And 13 Two examples of the arrangement of such intermediate parts 27 in the housing 3 of the electric heating device 1 are shown.

[0163] The fourth embodiment differs from the first embodiment in that the intermediate part 27 comprises contact tabs 277, 279 extending from the core 271, which do not all extend towards the same direction. In the example shown, the differently oriented tabs 277, 279 extend from the same region of the annular core 271, in this case from the same circumference.

[0164] In the example shown, the core 271 is generally annular. Alternatively, it can have the shape of a disc as in the first embodiment. When the intermediate part 27 is arranged in the housing 3, this core 271 is centred on an axis which coincides with the longitudinal axis A.

[0165] At least some of the contact tabs 277, 279 can be inclined with respect to the longitudinal axis A, for example forming an angle of about 30° to 45° before contact. In the example shown, the contact tabs 277, 279 are inclined with respect to the longitudinal axis A.

[0166] The tabs 277, 279 can be alternately inclined in different directions.

[0167] For example, first contact tabs 277 and second contact tabs 279 can be provided alternately, as shown.

[0168] The first contact tabs 277 can be directed towards the outside of the intermediate part 27, i.e. away from the centre of the intermediate part 27. All the first contact tabs 277 can have the same inclination with respect to the longitudinal axis A.

[0169] Conversely, the second contact tabs 279 can be directed towards the inside of the intermediate part 27, i.e. towards the centre of the intermediate part 27 or towards the longitudinal axis A. All the second contact tabs 279 have the same inclination with respect to the longitudinal axis A.

[0170] For example, as Figure 12 As shown schematically, when the heating body 11 is fitted in the housing 3, the intermediate part 27 can be fixed inside the housing 3 by abutment of the electrical heating element 7 (or, when the heating body comprises at least two electrical heating elements, by at least one of the electrical heating elements) against all the contact tabs 277, 279. In particular, mechanical contact is made with the distal end (relative to the base) of the winding portion 15 of the electrical heating element 7. The contact tabs 277 and 279 abut the electrical heating element 7 alternately inside and outside the electrical heating element 7.

[0171] This arrangement makes it possible to limit the longitudinal movement of the heating body 11 inside the housing 3.

[0172] According to Figure 13 In another example shown, the heating body 11 and the intermediate part 27 are mounted inside the housing 3 so that the contact tabs 277 and 279 support alternately against the first electrical heating element 7 and the second electrical heating element 9.

[0173] In particular, the first tabs 277 can be in contact with the first electric heating element 7 placed around the second electric heating element 9. As for the second contact tabs 279, they can be in contact with the second electric heating element 9. As a non-limiting example, the first tabs 277 can be arranged outside the first electric heating element 7. The second tabs 279 can be arranged inside the second electric heating element 9.

[0174] When the heating body 11 and the intermediate part 27 are assembled inside the housing 3, the electric heating elements 7, 9 can deform the contact tabs 277, 279, thereby ensuring mechanical contact.

[0175] Fifth embodiment

[0176] Figure 14 And 15 A fifth embodiment is shown, according to which several intermediate parts 28 in the form of clips or sliders are arranged to form several mechanical connection elements 21. This embodiment is suitable for a configuration of the heating body 11 with at least two concentric electric heating elements 7, 9.

[0177] Preferably, at least three intermediate parts 28 in the form of clips are provided. They are advantageously regularly distributed over 360°.

[0178] The intermediate part 28 comprises a head 281 and at least a first tongue or tab 283 and a second tongue or tab 285 extending from the head 281. In this example, the two tongues or tabs 283 and 285 have different lengths. The head 281 is advantageously a circular portion of the clip. In this example, the first, longer tab 283 can be straight or substantially straight. In this example, the second, shorter tab 285 can also be straight or substantially straight.

[0179] When assembled on the heating body 11, the head 281 is arranged to be supported on the electric heating elements, in particular on the outer electric heating element. This is the first electric heating element 7 in the example shown. The clip is thus held in place. The circular shape allows the head 281 to partially wrap around the tubular outer electric heating element 7.

[0180] The head 281 of the intermediate part 28 is arranged at the distal end of the winding portion 15 of the first electric heating element 7 relative to the base 5.

[0181] The first tab 283 extends between the two electric heating elements 7, 9, and the second tab 285 extends towards the outside of the heating body 11, and thus towards the periphery of the concentric electric heating elements 7, 9. When the assembly is installed inside the housing 3, the second tab 285 comes into contact with the inner surface of the housing 3, so that the first tab 283 is pushed and held against the inner electric heating element. This is the second electric heating element 9 in the example shown. The first tab 283 is thus wedged between the concentric electric heating elements 7, 9.

[0182] The length of the contact tabs 283, 285 is calculated to ensure contact between the second contact tab 285 and the inner surface of the housing 3, and between the clip and a predetermined number of windings of the inner electric heating element 9, for example at least two windings.

[0183] Figure 16 A variant of the intermediate part 29 is shown, which is similar to Figure 15 the fifth embodiment shown, in that the second tab 295 extending from the head 291 is less protruding. For example, it can be flat. Advantageously, the second tab 295 is dome-shaped or convex, with the convexity facing the inner surface of the housing 3. The dome shape avoids damaging the inner surface of the housing 3 when in mechanical contact with the clip.

[0184] The first tab 293 extending from the head 291 can be similar to Figure 15 the first tab 283 of the fifth embodiment shown. The rest of the description of the fifth embodiment applies to this variant.

[0185] Sixth embodiment

[0186] Figure 17 and 18 A sixth embodiment of the intermediate part 24 forming the mechanical connection element 21 is shown.

[0187] The sixth embodiment differs from the second embodiment in that the intermediate part 24 comprises two sets of tabs 243 and 245 extending from a central region of the core 241, for example in the form of a disc, first radially before being bent so as to extend towards the electric heating elements 7, 9.

[0188] The first tabs 243 are in contact with the first electric heating element 7 outside of the first electric heating element 7. The second tabs 245 are in contact with the second electric heating element 9, for example arranged between the two concentric electric heating elements 7, 9.

[0189] According to the example shown, the tabs 243, 245 are not all bent to the same length. They are alternately bent to two different lengths. This results in the first tabs 243 having a longer radial extension, while the second tabs 245 have a shorter radial extension.

[0190] According to this sixth embodiment, the tabs 243, 245 can all be bent so as to extend parallel to each other. Furthermore, in this example, the tabs 243, 245 extend in a direction parallel or substantially parallel to the longitudinal axis A, in the direction of the electric heating elements 7, 9. This portion of the tabs 243, 245 extending in the direction of the electric heating elements 7, 9 to ensure contact is referred to as a longitudinal extension.

[0191] The tabs 243, 245 have, for example, longitudinal extensions of different lengths. In this case, the longitudinal extension of the first tab 243 is shorter than the longitudinal extension of the second tab 245.

[0192] According to one or the other of the above-described embodiments, the second mechanical connection ensured by the one or more mechanical connection elements 21 is an additional connection that fixes the one or more electric heating elements 7, 8, 9 to the base 5. The one or more mechanical connection elements 21 make it possible to limit the movement of the one or more electric heating elements 7, 8, 9 of the heating body 11 within the casing 3.

[0193] The mechanical connection elements 21 can maintain a distance between the one or more electric heating elements 7, 8, 9 of the heating body 11 and the inner surface of the casing 3, for example the longitudinal end 33 of the casing 3 and / or the lateral face of the casing 3.

[0194] Furthermore, when the heating body 11 comprises a plurality of electric heating elements 7, 8, 9, the mechanical connection elements 21 can maintain the same distance between the electric heating elements 7, 8, 9 and little or no contact between them.

[0195] When used on a motor vehicle, it is possible to prevent the elements of the heating body 11 from colliding within the casing 3, thereby limiting the generation of noise.

Claims

1. An electric heating device (1) for heating a liquid, particularly for motor vehicles, comprising a heating body (11) and a housing (3) at least partially defining a liquid flow chamber (30), said heating body (11) comprising at least two concentric electric heating elements (7, 8, 9), said at least two concentric electric heating elements extending in the liquid flow chamber (30) and fixed to the inner wall of said device at least partially defining said liquid flow chamber (30) to form a first mechanical connection, characterized in that, The electric heating device (1) includes at least one mechanical connecting element (21) disposed inside the liquid flow chamber (30), the at least one mechanical connecting element mechanically connecting the at least two concentric electric heating elements (7, 8, 9) and the inner surface of the outer casing (3) extending towards the heating body (11), thereby forming a second mechanical connection different from the first mechanical connection, wherein the at least two concentric electric heating elements (7, 8, 9) include an outer electric heating element (7) placed around an inner electric heating element (8, 9), and the at least one mechanical connecting element (21) is at least partially disposed between the at least two concentric electric heating elements. Furthermore, the at least two electric heating elements (7, 8, 9) at least partially have a helical shape around a concentric axis, and the at least one mechanical connecting element (21) is arranged between the inner surface of the housing (3) and at least one winding of the at least two electric heating elements (7, 8, 9). Furthermore, the at least one mechanical connecting element (21) takes the form of an intermediate component disposed between the inner surface of the housing (3) and the heating element (11), the intermediate component comprising: The core is arranged laterally facing the longitudinal ends of the at least two electric heating elements (7, 8, 9); and a predetermined number of contact tabs extend from the core along the direction of the heating body (11) and are arranged to contact the helical windings of the electric heating elements (7, 8, 9).

2. The apparatus (1) according to claim 1, characterized in that, The heating element (11) includes a base (5) fixed to the housing (3), the housing (3) and the base (5) at least partially defining the liquid flow chamber (30), and wherein the first mechanical connection is located between the at least one electric heating element (7, 8, 9) and the base (5).

3. The apparatus (1) according to claim 2, characterized in that, The at least one mechanical connecting element (21) is arranged in the liquid flow chamber (30) opposite the base (5).

4. The apparatus (1) according to any one of claims 1 to 3, characterized in that, The at least one electric heating element (7, 8, 9) extends longitudinally in the liquid flow chamber (30), and wherein the at least one mechanical connecting element (21) is arranged in the liquid flow chamber (30) for mechanically connecting the inner surface of the housing (3) to the longitudinal end of the electric heating element (7, 8, 9).

5. The apparatus (1) according to claim 4, characterized in that, The heating element (11) includes at least two electric heating elements (7, 8, 9) arranged in each other's axial extension direction, and wherein at least one mechanical connecting element (21) is axially arranged between the two electric heating elements (7, 8, 9).

6. The apparatus (1) according to any one of claims 1 to 3, characterized in that, The intermediate components (23, 24, 25, 26, 27, 28, 29) are at least partially elastic and flexible.

7. The apparatus (1) according to claim 3, characterized in that, The core of the intermediate component is arranged to abut against the inner surface of the outer shell (3) opposite to the base (5).

8. The apparatus (1) according to claim 1 or 7, characterized in that, The heating element (11) defines a generally hollow shape, and wherein: The core of the intermediate component is generally annular in shape, with an inner diameter (di) smaller than the outer diameter (de), and wherein... A first set of tabs (263), referred to as inner tabs, extends from the inside of the annular shape toward the inside of the heating element (11), and a second set of tabs (265), referred to as outer tabs, extends from the outside of the annular shape toward the outside of the heating element (11).

9. The apparatus (1) according to claim 1 or 7, characterized in that, At least some of the contact tabs of the intermediate component are arranged between concentric electric heating elements (7, 8, 9).

10. The apparatus (1) according to claim 1, characterized in that, The intermediate component is made in the form of a clip, comprising: a head (281, 291) arranged to be supported on an external electric heating element (7); and at least a first tab (283) and a second tab (285) extending from the head (281, 291), such that the first tab (283) is arranged to abut against an internal electric heating element (9), and the second tab (285) is arranged to abut against an inner surface of the housing (3).

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