FR3035765A1 - ELECTRIC RADIATOR FOR HEATING AND AIR CONDITIONING DEVICE - Google Patents

Abstract

The present invention relates to an electric heater (10) for a heating and air conditioning device (1) for a motor vehicle (V). It is characterized in that the electric radiator (10) comprises: - at least one heat dissipation plate (12) comprising a plurality of ventilation orifices (120); and - at least one resistive heating element (11) adapted to be disposed on at least one of the faces (122, 123) of said heat dissipation plate (12).

Description

TECHNICAL FIELD OF THE INVENTION The present invention relates to an electric heater for a heating and air conditioning device for a motor vehicle.

It finds a particular but non-limiting application in motor vehicles. TECHNOLOGICAL BACKGROUND OF THE INVENTION Hybrid, electric and thermal motor vehicles comprise a heating and air conditioning device which comprises an electric radiator. In the case of hybrid and thermal vehicles, this radiator is an auxiliary radiator that heats the passenger compartment of the motor vehicle in addition to the main radiator, while in the case of all-electric vehicles, this radiator is the main radiator. This electric radiator is connected to the electrical network of the motor vehicle. An electric heater known to those skilled in the art comprises: a plurality of ceramic stones; a plurality of fins arranged around each ceramic stone and which are in mechanical and electrical contact with the ceramic stone. Each fin is electrically powered via the electrical network of the motor vehicle. In a non-limiting example, when the electric radiator is the main radiator of the motor vehicle, about twenty ceramic stones are used to provide a power of the order of 1200 Watts.

The fins allow to evacuate the heat produced by the ceramic stones and thus heat a flow of air that passes through the assembly formed by the ceramic stones and said fins.

A disadvantage of this state of the art is that this electric heater comprises a very large number of elements (stones and fins). In addition, the assembly of these elements must meet dimensional and geometric constraints because of the limited space that is allocated to the electric heater in the heating and air conditioning device.

The assembly of all the elements is thus complex to achieve. In this context, the present invention aims to solve the aforementioned drawback. GENERAL DESCRIPTION OF THE INVENTION To this end, the invention proposes an electric radiator for a heating and air-conditioning device for a motor vehicle, according to which the electric radiator comprises: at least one heat dissipation plate comprising a plurality of cooling orifices; ventilation; and at least one resistive heating element adapted to be disposed on at least one of the faces of said heat dissipation plate. Thus, as will be seen in detail below, the number of elements in the electric radiator has been reduced and the assembly of the elements has been simplified since it simply comprises at least one resistive heating element disposed on the surface. of the heat dissipation plate. The design of the electric radiator can thus be adapted more easily depending on the geometric and dimensional constraints of the heating and air conditioning device.

According to non-limiting embodiments, the electric radiator may further comprise one or more additional characteristics among the following: According to a non-limiting embodiment, said at least one resistive heating element comprises a resistive wire adapted to follow a determined path between said aeration openings. The design of the electric radiator can thus be adapted more easily depending on the thermal power required.

According to one nonlimiting embodiment, said resistive heating element is covered with a protective coating such as a resin. This protects the resistive heating element against corrosion due to corrosive agents such as water, salt, sulfur dioxide (SO2) etc.

According to a non-limiting embodiment, said heat dissipation plate is made of aluminum. This makes it possible to obtain a light and inexpensive plate.

According to a non-limiting embodiment, said heat dissipation plate comprises a zone devoid of ventilation orifices. This helps to concentrate a flow of air in certain areas of the heat dissipation plate.

According to a non-limiting embodiment, the ventilation openings have a depth equal to the thickness of the heat dissipation plate. According to a non-limiting embodiment, said heat dissipation plate further comprises on one of its faces studs comprising said aeration orifices. This makes it easy to walk the resistive wire around said orifices.

According to a non-limiting embodiment, said electric heater comprises a plurality of resistive heating elements. This makes it possible to obtain a fairly high power for an electric radiator. Moreover, each resistive heating element having a path different from the other, it makes it possible to obtain, if necessary, different powers depending on the zones to be thermally managed. According to a nonlimiting embodiment, each resistive heating element 10 is associated with an air outlet in a passenger compartment of the motor vehicle and each resistive heating element comprises electrical connections disposed on said heat dissipation plate on the side of said output of associated air. This arrangement is of interest in the case where there is independent air flow management for each air outlet. According to a non-limiting embodiment, each resistive heating element comprises electrical connections, and the electrical connections of all the resistive heating elements are arranged on the same side 20 of said heat dissipation plate. This allows for easier access to the electrical connections, and easier to connect the resistive heating elements to an external electrical or electronic device.

According to one nonlimiting embodiment, said resistive heating element comprises two electrical connections adapted to be connected to an electrical network of the motor vehicle. The electrical connections allow the resistive heating element to be energized and thus allow the resistive heating element to dissipate thermal energy.

According to one nonlimiting embodiment, the path of the resistive wire of said at least one resistive heating element is determined as a function of: the location of an air outlet in a passenger compartment of the motor vehicle; and / or the number of resistive heating elements disposed on said heat dissipation plate; and / or - the desired heating power. The path traveled by a resistive heating element is very adjustable according to all these parameters. The design of the entire electric radiator 10 is thus very flexible. According to a non-limiting embodiment, said electric radiator is adapted to deliver a heating power adapted according to: the resistivity of the material of said resistive wire; and / or the length of said resistive wire; and / or - the section of said resistive wire. These different parameters make it possible to easily and precisely adjust the heating power produced by the electric radiator.

It is also proposed a heating and air conditioning device for a motor vehicle comprising an electric heater according to any one of the preceding characteristics. According to a non-limiting embodiment, the electric radiator is a main radiator or an auxiliary radiator. Thus, the electric heater can be integrated in a heating and air conditioning device for a thermal automobile vehicle, hybrid or for an all-electric vehicle.

BRIEF DESCRIPTION OF THE FIGURES The invention and its various applications will be better understood on reading the description which follows and on examining the figures that accompany it. FIG. 1 represents a diagram of an electric radiator for a heating and air conditioning device for a motor vehicle, said electric radiator comprising a heat dissipation plate and at least one resistive heating element according to a first nonlimiting embodiment. of the invention; - Figure 2 shows a section along an axis A-A of the electric heater of Figure 1; - Figure 3 shows a cross section of the heat dissipation plate according to a first non-limiting embodiment; FIG. 4 represents a cross-section of the heat dissipation plate according to a second non-limiting embodiment; FIG. 5 shows a diagram of the resistive heating element of the electric radiator of FIG. 1 according to a nonlimiting embodiment, said resistive heating element comprising electrical connections and a resistive wire; FIG. 6 represents a diagram of an electric radiator for a heating and air-conditioning device for a motor vehicle, said electric radiator comprising a heat dissipation plate and at least one resistive heating element according to a second non-limiting embodiment of FIG. the invention; - Figure 7 shows a diagram of a heating and air conditioning device comprising the electric heater of Figure 1 or Figure 6 according to a non-limiting embodiment.

30 303 5 7 6 5 7 DESCRIPTION OF EMBODIMENTS OF THE INVENTION The identical elements, structure or function, appearing in different figures retain, unless otherwise specified, the same references.

The electric radiator 10 for a heating and air-conditioning device 1 for a motor vehicle V is shown schematically in FIG. 1. By motor vehicle, it is meant any type of motorized vehicle.

In the nonlimiting example illustrated, the radiator 10 is part of a heating and air conditioning device 1 (described in more detail in the following description). The electric heater 10 comprises: - at least one heat dissipation plate 12 comprising a plurality of ventilation orifices 120; at least one resistive heating element 11 adapted to be disposed on one of the faces 122, 123 of said heat dissipation plate 12.

The various elements of the electric heater 10 are described in more detail below. Heat Dissipation Plate The heat dissipation plate 12 is described with reference to Figures 1, 2, 3 and 6. In a non-limiting embodiment, the heat dissipation plate 12 is made of aluminum. This material is lightweight and allows very good heat dissipation. It has indeed a coefficient of exchange with the air 303 5 7 6 5 8 interesting which allows a good heat transfer. Moreover, it is an inexpensive material. In a non-limiting embodiment, the heat dissipation plate 12 comprises a height L1 between 80 mm (millimeters) and 160 mm 5 and a length L 2 between 150 mm and 300 mm. In a non-limiting embodiment, the heat dissipation plate 12 comprises a thickness el of between 10 mm and 15 mm. These dimensions make it possible to integrate said heat dissipation plate 12 in a restricted location in the heating and air-conditioning device 1 of the automobile vehicle V. Of course, other dimensions can be used. The ventilation holes 120 of the heat dissipation plate 12 make it possible to let a stream of air 6 pass through said heat dissipation plate 12.

The number of ventilation apertures 120 and their diameter is calculated as a function of the desired value of the pressure drop caused by the passage of an air stream 6 through said aeration openings 120. In one example non-limiting embodiment, the pressure loss sought is between 3060 Pascal for a mass flow rate of 300kg / h.

The heat dissipation plate 12 thus makes it possible to transmit the energy produced by the resistive heating element 11 to the air flow 6 passing through the ventilation orifices 120, which makes it possible to heat said air flow 6.

In a non-limiting embodiment as illustrated in FIG. 1, the heat dissipation plate 12 comprises a zone 121 devoid of ventilation orifices 120. Thus, it is possible to densify the air flow 6 in certain zones. of the heat dissipation plate 12 and have no air flow in some other areas if it is useless to have in these places.

In another non-limiting embodiment as shown in FIG. 6, the heat sink plate 12 does not include such a zone. It therefore comprises a plurality of ventilation holes 120 distributed over its entire surface (as shown in FIG. 6). In a first non-limiting embodiment illustrated in FIG. 3, the aeration orifices 120 have a thickness e2 equal to the thickness e1 of the heat dissipation plate 12. Thus, the aeration orifices 120 open on the two faces 122 and 123 of the heat dissipation plate 12 and do not exceed said faces. Such aeration holes 120 are illustrated on the section A-A of FIG.

In this case, in a non-limiting embodiment, the heat dissipation plate 12 may comprise locating pins 130 to enable the path Pth of a resistive wire 110 to be made, said resistive wire 110 being able to be wound in part around said pawns. These pins 130 thus serve as guides for the resistive wire 110.

In a second non-limiting embodiment, the heat dissipation plate 12 further comprises on one of its faces (122, 123) pads 140 comprising said ventilation holes 120. These pads thus make it possible to carry out the path of a resistive wire 110, said resistive wire 110 being able to be wound partly around said studs 140. The thickness e2 of the ventilation orifices 120 is thus greater than that of the heat dissipation plate 12. These studs 140 thus form the contour of the aeration orifices 120 and said contours thus serve as a guide for the resistive wire 110. As illustrated in FIG. 4, in a first non-limiting embodiment, a stud 140 is projecting on one of the faces of the heat dissipation plate 12, here the face 122. In this case, in a non-limiting example, the pad 140 is a pad made by stamping. In a second variant of non-limiting embodiment (not shown), a stud 140 is projecting on both sides of the thermal dissipation plate 12. In this case, in a non-limiting example, the stud 140 is an attached stud. Resistive heating element The resistive heating element is described with reference to FIGS. 1, 5 and 6.

In a non-limiting embodiment, a resistive heating element 11 comprises: a resistive wire 110 adapted to follow a determined path Pth between said aeration orifices 120; and two electrical connections 113, 114 adapted to be connected to an electrical network 2 of the motor vehicle V. The electrical network 2 is constituted inter alia by a battery Bat of the motor vehicle V as illustrated in FIG.

In one nonlimiting embodiment, the electric heater 10 comprises a plurality of resistive heating elements 11. In a first non-limiting embodiment illustrated in FIG. 1, each resistive heating element 11 is associated with an air outlet. 5a, 5b, 5c, 5d (described later) in a passenger compartment 20 of the motor vehicle V and each resistive heating element 11 comprises electrical connections 113, 114 disposed on said heat dissipation plate 12 on the side of said air channel associated. As can be seen in FIG. 1, there are thus four resistive heating elements 11 with respective electrical connections 113a-114a, 113b-114b, 113c-114c, 113d-114d respectively associated with: - an air outlet 5a; an air outlet 5b; an air outlet 5c; An air outlet 5d.

The electrical connections of different resistive heating elements 11 can thus be arranged on different sides of the heat dissipation plate 12. Thus, as shown in the nonlimiting example of FIG. 113a, 114a and 113b, 114b are arranged on the same side 125, the electrical connections 113c, 114c are arranged on another side 124 and the electrical connections 113d, 114d are disposed on another side 126 of the heat dissipation plate 12. In a second nonlimiting embodiment illustrated in FIG. 6, each resistive heating element 11 comprises electrical connections 113, 114, and the electrical connections 113, 114 of the set of resistive heating elements 11 are arranged on a same side 124 of said heat dissipation plate 12. The heat dissipation plate 12 can thus be positioned in the chopper device. blower and air conditioning 1 so that the side 124 is easily accessible. The resistive wire 110 is connected to the two electrical connections 113 and 114 described above. Thus, a current flows through the resistive wire 110 through the voltage applied to the two electrical connections 113 and 114 and the resistive wire 110 will thus heat and deliver a heating power P of a certain value. The electric power is thus transformed into energy at a certain power (expressed in Watts). The energy that is here heat is transmitted via the resistive wire 110 to the heat dissipation plate 12. In a non-limiting embodiment, the resistive wire 110 is enameled copper alloy. Enameling is an electrical insulating layer which makes it possible to avoid any short circuit between the resistive wire 110 and the heat dissipation plate 12. Moreover, this makes it possible to avoid any short circuit between the turns themselves of said wire. resistive 110. In a non-limiting embodiment, the resistive wire 110 is a positive temperature coefficient (PTC). Thus, when the temperature of the resistive wire 110 increases, its resistance increases. In case of high temperature (in a non-limiting example between 130 ° C (Celsius) and 180 ° C), this limits the heating power P produced. This prevents overheating which could damage the resistive wire 110.

The resistive wire 110 travels a determined path Pth on the heat dissipation plate 12. In a non-limiting embodiment, the path Pth of the resistive wire 110 of said at least one resistive heating element 11 is determined as a function of: 10 - a ) the location of an air outlet 5a, 5b, 5c, 5d in a passenger compartment 20 of the motor vehicle V; and / or - b) the number of resistive heating elements 11 disposed on said heat dissipation plate 12; and / or - c) the desired heating power P.

With regard to point a), thanks to the path Pth, the resistive wire 110 may be disposed closer to the air outlet associated therewith. The mixing chamber 21 (described later) of the heating and air-conditioning device 1 can thus more easily send a mixed air flow with the right proportions of hot air flow as a function of the proportion of hot air desired. by a user on a given air outlet. Thus, for example, a resistive wire 110 may be associated with an air outlet 5a close to the windshield and its path Pth configured closest to said air outlet 5a so that the mixing chamber 21 recovers the most 25 easily air stream 6 heated by said resistive wire 110 and easily sends it to said air outlet 5a. With regard to point b), the path Pth makes it possible to take into account the other paths Pth traversed by the other resistive wires 110 so that the different resistive wires do not overlap.

As regards point c), the path Pth makes it possible to adapt the heating power P delivered by the resistive heating element 11. For this purpose, the length L of the resistive wire 110 is more or less less and so the path Pth is larger or smaller.

In the case where an independent management of the heated airflow 6 delivered to each air outlet 5a to 5d is performed, this allows for example to heat up the air flow 6 for the air outlet 5a for defrosting the air flow 6 for the air outlet 5b which corresponds to the air outlet for the driver. By independent management of air flow 6, it is meant that one can have for an air outlet a flow of hot air 6 at a temperature different from a flow of hot air 6 from another outlet. air. Thus, the resistive heating elements 11 of the electric heater 10 each comprise a resistive wire 110 which follows a path Pth between said ventilation apertures different from the other resistive wires 110. Each resistive heating element 11 thus dissipates a clean power P and if necessary different. This makes it possible to have an electric heater whose resistive heating elements can be modulated independently of each other. This path Pth thus makes it possible to adapt the design of the electric radiator 20 as a whole, taking into account not only the power demanded for the electric radiator 10 by a car manufacturer, but also the geometrical and dimensional constraints required by said car manufacturer. The adaptation is simple to achieve since a resistive wire 110 is easily mechanically operable.

Any path Pth can thus be envisaged. In a non-limiting embodiment, the resistive heating element 11 is covered with a resin 13 (illustrated in FIG. 2). The resin 13 thus covers the resistive wire 110 of the resistive heating element 11 and the portion of the electrical connections 113,114 of the resistive heating element 11 which is on said heat dissipation plate 12. The resin 13 is thermally conductive and electrically insulating. It thus facilitates the heat transfer between said resistive heating element 11 and the heat dissipation plate 12, and protects the resistive wire 110. In a nonlimiting example, the resin is a silicone that makes it possible to absorb the expansions of the material (here aluminum) of the heat dissipation plate. Thus, the silicone will not have cracks despite the expansions that the heat dissipation plate 12 may undergo under the effect of temperature variations. This resin 13 also makes it possible to protect the resistive heating element 11 against corrosion due to salt spray, salt air, pollutants of SO 2 type, etc. In one nonlimiting embodiment, the resin 13 is deposited on the resistive heating element 11 after removal of the latter on one of the faces of the heat dissipation plate 12, namely once the path Pth resistive wire 110 made. The resin 13 thus covers the heat dissipation plate 12 and thus makes it possible to electrically isolate the assembly of the heat dissipation plate 12.

The sectional view AA of FIG. 2 illustrates the resin 13 which thus protects the entire heat dissipation plate 12. In a non-limiting embodiment, said resistive heating element 11 (and therefore said electric radiator 10) is adapted to produce a power 25 P adapted function of: the resistivity p of the resistive wire material 110; and / or - the length L of the resistive wire 110; and / or the section S of the resistive wire 110 Thus, it is easy to modify the heating power P produced by all the resistive heating elements 11 according to one of these parameters without modifying the dimensions of the plate. heat dissipation 12 which accommodates said resistive heating elements 11. Thus, the heating power P delivered by a resistive heating element 11 may be identical or different from that delivered by another resistive heating element 11 on the same heat dissipation plate 11 As previously mentioned, the heating power P produced by a resistive heating element 11 can thus be adapted as a function of the air outlets 5a, 5b, 5c, 5d of the heating and air-conditioning device 1.

In the case of an all-electric vehicle, when the electric radiator forms the main radiator of the motor vehicle, in a non-limiting example, the total heating power P produced by all the resistive heating elements 11 is between 4 and 9kW (kilowatts). Note that in this case, the electric heater 10 is connected to the electrical network 2 of the motor vehicle via a battery Bat which provides substantially between 280 and 300 volts in a non-limiting example. To obtain this energy, either a single heat dissipation plate 12 is used with a plurality of resistive heating elements 11, or a plurality of thermal dissipation plates 12 are used, a heat dissipation plate having in this case one or more Resistive heating elements 11. In a non-limiting example, the heat dissipation plates 12 are arranged one behind the other. Thus, if for example one wants to obtain 4kW, a heat dissipation plate 12 providing 4kW may be used or two heat dissipation plates 12 providing 2kW each may be used. In the case of a hybrid or thermal vehicle, when the electric radiator forms an auxiliary radiator of the motor vehicle, in a non-limiting example, the total heating power P produced by all the resistive heating elements 11 is between 300W. and 2kW. Note that in this case, the electric heater 10 is connected to the electric network 2 of the motor vehicle via an alternator Bat battery which provides substantially between 12 and 24 volts in a non-limiting example.

FIG. 7 is a diagram illustrating the electric radiator 10 integrated in a heating and air-conditioning device 1. It will be noted that in a non-limiting example, the heating and air-conditioning device 1 is located at the central console of the 10 car vehicle V behind the dashboard. In the nonlimiting example illustrated, the electric radiator 10 is an auxiliary radiator. As can be seen in Figure 7, in a non-limiting embodiment, the heating and air conditioning device 1 comprises in particular - an air inlet 4 through which the air flow 6 can enter; a blower 3 arranged facing the air inlet 4 adapted to circulate the air flow 6 from the air inlet 4 to the air outlets 5a, 5b, 5c and 5d; an evaporator 7 connected to a refrigerant circuit (not shown), said evaporator 7 being adapted to cool the air flow 6; - A cold air chamber 11 disposed downstream of the evaporator 7 and adapted to receive the air stream 6 cooled by the evaporator 7; A heating chamber 12 comprising a main radiator 8 and the auxiliary electric radiator 10 and adapted to heat the air flow 6 - an air mixing chamber 21 adapted to: - receive the flow of cold air from the cold air chamber 11 and the hot air stream from the heating chamber 12; delivering a mixed air flow to each of the air outlets 5a to 5d.

Mixed air flow means a flow of air from the mixing chamber 21. This air flow may comprise a mixture of cold air flow and hot air flow or only the flow cold air or hot air flow.

Thus, the air mixing chamber 21 comprises an air mixing unit (not shown) which makes it possible to calibrate the proportion of cold air flow and of hot air flow entering said mixing chamber 21. To obtain the mixed air flow, the mixing chamber 21 is thus fed with portions of hot air flow and cold air flow or with a totally cold air flow or with an air flow. totally hot. Note that each of the air outlets 5a, 5b, 5c and 5d is intended to deliver a respective air flow in a specific area of the passenger compartment of the motor vehicle V and the pivoting adjustment flaps (not shown), allow to adjust according to the demands of a user the amount of air flowing through each of these air outlets. Thus, the air outlet 5a is adapted to distribute air in the upper part of the upper front area of the passenger compartment of the vehicle, namely at the windshield.

The air outlet 5b is adapted to distribute air in the upper part of the central front area of the passenger compartment of the vehicle, namely at the level of the driver. The air outlet 5c is adapted to distribute air in the lower part of the lower front area of the passenger compartment of the vehicle, namely at 25 feet of the driver. The air outlet 5d is adapted to distribute air in the upper and lower portions of the central and lower front zones of the passenger compartment of the vehicle, namely at the front passenger and front passenger feet.

Of course, in another embodiment, there may be two differentiated air outlets, one for the front passenger and one for the front passenger feet. Note that this other mode would imply for an independent management of the air flow for each air outlet a fifth resistive heating element 11 disposed in a non-limiting example on the side 124 (right) of the heat dissipation plate.

Of course, the description of the invention is not limited to the embodiments described above. Thus, in a non-limiting embodiment, the electric radiator 10 can integrate into a device which is a heating device independent of the air conditioning device of the motor vehicle. Thus, in a non-limiting embodiment, a metal for dissipating heat other than aluminum may be used for the heat dissipation plate 12.

Thus, in a non-limiting embodiment, the two faces of said heat dissipation plate may comprise at least one resistive heating element. In this case, studs or studs are used.

Thus, the described invention has the following advantages in particular: it is a simple solution to implement and inexpensive; it makes it possible to propose an electric radiator whose geometry is simple; it makes it possible to propose an adaptable electric radiator according to the demand of the car manufacturers (power, dimensions); it makes it possible to propose an electric heater which is simpler to manufacture and which has few elements and whose design is very flexible. The heat dissipation plate 12 is cut in the desired format according to the manufacturer's application and in particular the space allocated for the electric radiator; the length of the resistive wire is determined according to the desired heating power, etc. ; - it allows to propose an electric heater whose resistive heating elements can be isolated very simply (thanks to the resin) and without significant additional cost to manufacture; - It allows to manufacture an electric heater on a fully mechanized chain 5 without human intervention, especially because the electric heater has simple elements to manufacture, to assemble. It suffices to use in particular a stamping tool for cutting the heat dissipation plate and the ventilation holes (in the case of ventilation orifices with pins or 10 pads projecting on one side ), an insertion tool in the case of studs on two sides, a positioning tool for making a path Pth, and a welding tool for making the connections to the electrical connections; it makes it possible to propose an electric radiator in which it is not necessary to make a compromise between the power dissipated and the geometry, the dimensions of the electric radiator unlike the state of the prior art; it makes it possible to propose an electric radiator whose power is easily adjustable by changing just one or more parameters of the resistive wires (resistivity, length, section) and the number of resistive heating elements without changing the geometry of the elements or their dimension ( heat dissipation plate); it makes it possible to propose different ranges (in power) of resistive heating elements 11 on the same heat dissipation plate 12; it makes it possible to propose an electric radiator that can be used to heat with different powers, different air flows intended for different outlets so that the said air flows do not necessarily have the same temperature. A user can thus decide to have a homogeneous heating on the different air outlets, or a heating at different temperatures according to the air outlets.

Claims (15)

REVENDICATIONS1. Electric radiator (10) for a heating and air-conditioning device (1) for a motor vehicle (V), wherein the electric radiator (10) comprises: - at least one heat dissipation plate (12) comprising a plurality of orifices aeration (120); and - at least one resistive heating element (11) adapted to be disposed on at least one of the faces (122, 123) of said heat dissipation plate (12). 2. An electric radiator (10) according to claim 1, wherein said at least one resistive heating element (11) comprises a resistive wire (110) adapted to follow a determined path (Pth) between said aeration holes (120). An electric heater (10) according to claim 1 or claim 2, wherein said resistive heating element (11) is covered with a protective coating such as a resin (13). The electric radiator (10) according to any of claims 1 to 3, wherein said heat dissipation plate (12) is aluminum. The electric radiator (10) according to any one of claims 1 to 4, wherein said heat dissipation plate (12) has a zone (121) free of vents (120). 303 5 7 6 5 21 6. Electric radiator (10) according to any one of claims 1 to 5, wherein the aeration holes (120) have a depth (e2) equal to the thickness (el)) of the heat dissipation plate ( 12). 5 7. Electric radiator (10) according to any one of claims 1 to 5, wherein said heat dissipation plate (12) further comprises on one of its faces (122, 123) pads (140) comprising said apertures aeration (120). 10 The electric heater (10) according to any one of claims 1 to 7, wherein said electric heater (10) has a plurality of resistive heating elements (11). 15 9. electric radiator (10) according to claim 8, wherein each resistive heating element (11) is associated with an air outlet (5a, 5b, 5c, 5d) in a passenger compartment (20) of the motor vehicle (V and each resistive heating element (11) comprises electrical connections (113, 114) disposed on said heat dissipation plate (12) on the side of said associated air outlet (5a, 5b, 5c, 5d). 10. An electric radiator (10) according to claim 8, wherein each resistive heating element (11) comprises electrical connections (113, 114), and the electrical connections (113, 114) of the set of resistive heating elements. (11) are arranged on the same side (124) of said heat dissipation plate (12). 30 11. An electric radiator (10) according to any one of claims 1 to 10, wherein said resistive heating element (11) comprises two electrical connections (113, 114) adapted to be connected to an electrical network (2) of the motor vehicle (V). 303 5 7 6 5 22 An electric radiator (10) according to any one of claims 2 to 11, wherein the path (Pth) of the resistive wire (110) of said at least one resistive heating element (11) is determined as a function of: locating an air outlet (5a, 5b, 5c, 5d) in a passenger compartment (20) of the motor vehicle (V); and / or - the number of resistive heating elements (11) disposed on said heat dissipation plate (12); and / or 10 - the desired heating power (P). 13. Electric radiator (10) according to any one of claims 2 to 12, wherein said electric radiator (10) is adapted to deliver a heating power (P) adapted according to: the resistivity (p) of the material said resistive wire (110); and / or - the length (L) of said resistive wire (110); and / or the section (S) of said resistive wire (110). 20 14. Heating and air conditioning device (1) for a motor vehicle (V) comprising an electric radiator (10) according to any one of claims 1 to 13. 15. Heating and air conditioning device (1) according to claim 14, wherein said electric radiator (10) is a main radiator or an auxiliary radiator.