FR3037867A1 - HEATING BLOCK FOR AN ELECTRICAL RADIATOR OF A HEATING SYSTEM OF A MOTOR VEHICLE - Google Patents

Abstract

The invention relates to a heating block (1) for an electric heater (2) of a ventilation, heating and / or air conditioning of a motor vehicle, the heating block (1) comprising at least one body heater (7) which comprises at least one heating element (9) and a frame (4) whose edges (5, 5 ', 6) delimit an internal recess in which the heating element (7) can be arranged, characterized in that the heating body (7) comprises at least one heating unit (E1, E2) comprising at least two plates (8, 8 ', 8', 8 '') which comprises openings (10), and at least a heating element (9) disposed between the plates (8, 8 ', 8', 8 '').

Description

FIELD OF THE INVENTION The field of the present invention is that of ventilation, heating and / or air conditioning equipment fitted to motor vehicles. The present invention more particularly relates to electric heaters equipping such installations. The electric heater of the present invention is of the type having heating elements, such as positive temperature coefficient resistors, mounted on a frame shaped frame to heat a flow of air therethrough. Ventilation, heating and / or air conditioning installations for motor vehicles commonly comprise one or more electric radiators arranged in a pipe allowing the flow of an air flow. Such an electric radiator is commonly used as an additional radiator providing an almost immediate heat supplement inside the vehicles deficient in heat at startup. It should however be noted that one or more electric radiators may constitute a main source of heat, allowing itself to raise and / or maintain at a set temperature the flow of air flowing inside. of driving. The electric radiator essentially comprises an assembly formed by at least one heating block and by a connector connected to the heating block. Connectivity allows to connect the heating block to the on-board electrical network for its power supply, or even to control means and / or control the operation of the electric heater. The heating block mainly comprises a chassis carrying at least one heating body. The frame is generally arranged in a generally flat frame housing the heating body in its inner recess. The frame is disposed inside the pipe, so that the airflow flows through its inner recess perpendicular to the general plane of the frame. The at least one heating body comprises electric energy heating elements, such as positive temperature coefficient resistors. The chassis is equipped with holding members or the heating body in its inner recess. The chassis frame arrangement allows the flow of air to pass through the heater body to cause a rise in temperature of the airflow when the heater is powered with electrical energy. For example, reference may be made to document EP 1 821 575 which describes such an electric radiator comprising a heating block which comprises a frame arranged in a frame. The inner recess of the frame has respective receiving housings of a plurality of heaters. The housings are arranged between longitudinal and lateral partitions extending into the recess inside the frame. The walls of the housing comprise holding members of the heating bodies. The heating bodies are introduced into the housings, by proceeding in a translation movement along an axis 15 substantially parallel to that of the longitudinal axis of the frame, in the manner of a drawer. An electric radiator according to EP 1 821 575 comprising a frame of the aforesaid type can thus be produced at the lowest possible costs. For this purpose, it is sought a simple chassis structure that allows the exploitation of common commercial heating elements to constitute the heating bodies. It is also sought to limit the number of assembly operations to be performed for the assembly between them of the components of the radiator.

The present invention is part of the pursuit of such a research, constant in the context of a severe industrial competition in the automotive field. Such competition requires sustained research efforts to reduce the cost of obtaining accessories for motor vehicles, while improving their performance if possible.

In this context, the object of the present invention is to provide an electric heater fitted to a ventilation, heating and / or air conditioning system of a motor vehicle. It is more particularly sought by the present invention to simplify as well as possible the structure of the electric radiator and to make it possible to obtain it at lower cost, and preferably by improving its performance. Thus, the present invention relates to a heating block for an electric radiator 5 equipping a ventilation system, heating and / or air conditioning of a motor vehicle. As a reminder, such a heating block essentially comprises a frame arranged in a frame and provided with members for holding at least one heating element comprising heating elements, such as resistors with a positive temperature coefficient.

As a result, the present invention also relates to an electric heater for a ventilation, heating and / or air conditioning of a motor vehicle. As a reminder, such an electric radiator comprises at least one said heating block and a connector for connecting the heating block to at least one source of electrical energy, the on-board electrical network of a motor vehicle in particular, or possibly also to means for controlling and / or controlling the operation of the electric radiator. As previously referred to, the electric radiator is commercially competitive, by simplification of its structural organization and the methods used to obtain it. Such methods of obtaining the electric radiator must take into account both the individual achievement of its components, including heating and chassis, that the assembly of these components together. More particularly, the manufacturing operations of the components of the electric heater must be simplified and easy to implement. The structural organization of the components of the electric radiator is sought simple and able to provide an assembly between them industrially easy to achieve, at lower cost.

It must also be taken into account the search for an optimization of the performance of the electric radiator and a simplification of the methods of electrical connection of the heating block to the on-board electrical network, and possibly also to means of control and control. / or controlling the operation of the electric heater.

The heating block is also desired capable of possibly conferring on the electric radiator the capacity to constitute a main source of heat, allowing itself to raise and / or maintain at a set temperature a flow of air on the crossing, and that with periods of implementation as short as possible. To this end, it is sought an organization of the heating block to easily modulate the number of heating elements that can be installed on the frame according to the caloric requirements to be provided to heat the air flow at a given set temperature. Still for this purpose, it is also desirable to arrange the heating block to provide optimum utilization of the heat produced by the heating elements that it comprises. It is also expedient to reduce the size of the heating block according to its thickness, without affecting the performance of the heating body relative to the rise in temperature of the air flow to be heated. Such a reduction in size facilitates the implantation of the electric radiator inside a pipe conveying the flow of air. The crossing of the heating block by the air flow must be promoted by optimizing the heat exchange between them.

Thus, the present invention relates to a heating block for an electric heater of a ventilation, heating and / or air conditioning of a motor vehicle. The heating block comprises at least one heating element which comprises at least one heating element and a frame whose edges delimit an internal recess in which the heating element can be arranged, characterized in that the heating element comprises at least one heating assembly comprising at least two plates which has openings, and at least one heating element arranged between the plates.

In this way, the heating block of the present invention comprises a limited number of components whose structure and arrangement between them nevertheless make it possible to optimize the heat exchange between the heating element and a flow of air passing therethrough.

According to non-limiting embodiments, the heating block may further comprise one or more additional characteristics from the following: According to a non-limiting embodiment, the chassis of the heating block comprises holding members making it possible to maintain the heating body in the inner recess and maintain the plates on the chassis. According to a non-limiting embodiment, said holding members 10 hold the plates on the frame so that these plates extend away from one another. The holding members thus advantageously make it possible to keep the plates in a distant superposition. The plates are held in pairs at a distance from each other by arranging the space between them for receiving the heating elements in pairs. The remote holding of the plates in pairs can be easily obtained by the interposition between them of the heating elements and / or by means of said holding members respectively assigned to one and the other of the plates to fix the body of heats up on the chassis.

In other words, the heater has at least one generally planar heater set in its general plane inside the recess of the chassis. Of course, the recess of the frame is delimited by the inner recess of the frame defining its conformation. Said at least one heating unit is installed on the frame by means of the holding members and comprises, in successive superposition perpendicular to the overall plane of the frame, a first plate, the heating elements, and a second plate. The space between the plates provides a chamber within which the heating elements are housed, being held prisoner between the plates. The components of the heating body can be limited in all and for all to a plurality of plates, at least two in number, and to the heating elements interposed therebetween.

Advantageously, the plates extend substantially parallel to the general direction of extension of the frame. According to a non-limiting embodiment, said holding members are arranged on at least two opposite edges of the frame, these holding members are engaged with the edge of the slices of the plates. In this way, the holding members hold the heating body through the plates.

According to one embodiment, such fastening members may be of the threaded member type or the interlocking type being disposed at intervals on the edges of the frame. Said interlocking may be an interlocking elastically deformable fasteners, for example arranged in clips. Such elastic deformation is able to compensate for a potential deformation of the plates, of small thickness, during their change in temperature. In other words, such fastening members with elastic deformation make it possible to allow deformation of the plates while avoiding placing them under stress in their general plane during the temperature variations to which the heating body is subjected. In addition, as referred to later, it is advantageous to form the plates from an electrically conductive material and consequently electrically isolate the plates vis-à-vis the chassis. In this case, the fasteners can be easily derived from an electrically insulating material, such as a plastic material.

According to a nonlimiting embodiment, said holding members are slides arranged along at least two opposite edges of the frame, each of the opposite edges of the frame having at least two respective receiving rails of the plates via the edge of their slice. According to a non-limiting embodiment, the slides extend in the thickness of the edges of the frame.

The said opposite edges of the frame are preferably extended according to the largest dimension of the frame in its overall plane. The slides help reinforce the maintenance of the plates in their general plan. The plates may be mounted to the frame by translation in their general plane along the overall plane of the frame from any of its edges perpendicular to said opposite edges. Alternatively, a clearance may be provided between the slides and the plates to compensate for any deformation of the plates as a result of their temperature change. It can thus be avoided to place the plates under stress during temperature variations to which the heating body is subjected. Such a game is also advantageous for facilitating the sliding of the plates along the slides.

The frame may be devoid of one of the edges of the frame, oriented perpendicular to said opposing edges, from which edge the plates may be introduced into the slideways. According to one variant, the chassis may comprise a section mounted removably on the chassis. Such a removable profile allows by withdrawal the introduction of the plates inside the slides for their assembly to the frame. According to a non-limiting embodiment, the plates are made of an electrically conductive material. The plates can thus constitute conduction members of an electric current to the heating elements for their supply of electrical energy. Preferably, the plates have a substantially parallelepiped shape.

According to a nonlimiting embodiment, the plates each comprise at least one tab forming an electrical connection member. Such a tab is in particular intended to cooperate with a connector to provide the electrical power supply of the heater. Such a tab can be easily cut by cutting during the formation of the plates.

Preferably, each tongue is connected to one of the edges of a plate. Preferably, said tabs have a substantially parallelepiped shape.

It should be noted that the plates are both heat dissipating members for heating the air flow and electrical conduction members. Thus, the plates are electrical power supply members of the heating elements. One of the plates is connected to an electrically positive terminal while the other plate is connected to an electrically negative terminal. The plates are able to convey an electric current to the heating elements, from a source of electrical energy to which is connected the heating block through the plates. Of course, the exchange of electrical energy between the plates and the heating elements is advantageously achieved by contacting the plates of the heating elements. According to a non-limiting embodiment, the frame is made of an electrically insulating material.

It is understood that since the plates are conductive, it is necessary to electrically insulate the plates relative to one another. It is for this purpose leveraged the individual holding members of the plates equipping the frame. According to a simple embodiment, it is advantageously chosen to form the frame from an electrically insulating material and to arrange the holding members according to said slides. More particularly, it is preferably proposed to arrange the slides in the thickness of the edges of the frame, the frame being derived from an electrically insulating material, such as for example a polyamide-based material. According to a variant as previously described, the electrical insulation between the frame and the plates can be provided by holding members arranged as fastening members from an electrically insulating material.

Preferably, the frame has a substantially parallelepiped shape.

According to a non-limiting embodiment, the frame comprises a resin filled with reinforcing fibers, indifferently organic or mineral. Such a material is capable of conferring on the chassis a robustness that is capable of intrinsically maintaining the chassis in conformation, and this despite the rise in temperature of the heating element. For example, the frame is derived from a polyamide loaded with glass fibers or carbon fibers. The filler incorporated in the resin may also be a carbon powder. However, it may be desired to reinforce the robustness of the chassis, particularly in the case where the heating block is widely extended in its general plane. For this purpose, the robustness of the frame can be supported by a frame disposed on the large outer faces of the frame and between its edges. If necessary, such a frame is preferably derived from an electrically insulating material to avoid any risk of short circuit.

According to a non-limiting embodiment, the frame comprises a stiffening reinforcement whose elements each preferably extend between two opposite edges of the frame.

The frame can be easily integrated into the frame and / or bonded. Such an armature is formed in particular ribs arranged crosswise and / or longitudinal members interposed between the edges of the frame following one and / or the other of its two dimensions defining its general plane.

Thus, incidentally, the frame comprises a stiffening armature disposed in the general plane of the frame at its large outer faces. According to a non-limiting embodiment, said openings of a plate are arranged in staggered relation to the openings of an adjacent plate.

According to a nonlimiting embodiment, said openings are arranged for each of the plates in staggered rows, being separated from each other by a fraction of material, the openings of a plate being arranged opposite a fraction of material of the other plate. The openings of a plate are thus arranged opposite a solid part of material of the adjacent plate. The fraction of material thus advantageously prevents a frontal circulation of the flow of air through the heating body.

These arrangements are such that the plates of the same heating unit form between them baffles between the openings of a plate and the openings of the other plate. The baffles force the flow of air to circulate along the plates during the crossing of the heating body, and more particularly along the faces of the plates facing one another. More particularly, such baffles 15 constrain the flow of air passing through a heating assembly to lick the facing surfaces of the plates, since its escape from any aperture of a plate until it is admitted through any aperture of the other plate. Thus, the heat exchange between the heating body and the air flow is optimized.

The relative arrangement of the openings of one plate relative to the openings of the other plate is easy to obtain, and this without affecting an optimal number of openings formed through each of the plates. Indeed, it is easy to shift according to the extension dimensions of the plates in their general plane, the staggered arrangement of the openings of a plate relative to the openings of the other plate. In addition, the openings can be simultaneously performed through the two plates placed in superposition in their general plan to a workstation. Indeed, it can be put to advantage later a 180 ° turnover in its general plane of one of the plates relative to the other plate, to obtain said offset between the openings of a plate and the openings of the other plate.

The openings are potentially formed by piercing the plates. However, it is preferred to form the perforations by repressions of the material from the plates, such as by punching. Indeed, such material discharges can be used to stiffen the plates and / or to form corridors for channeling the flow of air flowing through the heating body. According to a non-limiting embodiment, the openings are formed through the plates by material discharge. The reprocessed material is advantageously a means for stiffening the plates in their general plane. According to a non-limiting embodiment, the material discharged from at least one of the plates is oriented towards the outside of the heating body, forming a channel for channeling a flow of air dedicated to circulate through the block. heating.

In the case where the heating body comprises a single heating unit, the material discharged from one and the other of the plates is advantageously directed towards the outside of the heating body.

In the case where the heating body comprises several heating assemblies, the material discharged from the two constituent plates of each of the heating assemblies is oriented in the same direction. As a result, in the latter case, the relative dimensions between the extension dimension of the material discharges and the thickness of the heating elements oriented perpendicular to the general plane of the plates are to be considered. Indeed in the latter case, it is expected to extend the material backflow perpendicular to the general plane of the plates significantly less than the thickness of the heating elements. Such arrangements make it possible not to affect the contact between the heating elements and the one and the other of the plates 25 of the same heating unit. It is forbidden to press the material backs of one plate against the other plate to prevent the material back-ups from generating localized stresses against the plates, and to prevent the plates being electrically conductive, the creation of a short circuit by direct contact between the plates.

According to one nonlimiting embodiment, said plates each comprise portions of material comprising respective receiving locations of the heating elements. Preferably, at least a portion of said material portions of a plate is disposed facing at least one portion of the material portions of the other plate. The portions of material leaving said locations may be incidentally slightly hollowed out by conferring on the locations a cradle-like conformation of the heating elements. Such digging may be formed by deformation of said surface portions, such as by a stamping operation of the plates. Such an embossing operation can be easily performed simultaneously with punching perforations through the plates. Such arrangements may be useful to facilitate spontaneous rigorous positioning of the heating elements at their respective locations when they are deposited on one of the plates and covered by the other of the plates. According to a non-limiting embodiment, the heating elements are held in position on the plates by means of a sealing material. Such a sealing material is not a silicone-based glue. The sealing of the heating elements on one of the other plates is advantageously used to provide a one-piece arrangement of the heater assembly.

It should be noted that in this case the heating elements comprise, in particular, surface irregularities which form retention niches for the sealing material. Such arrangements permit electrical contact between the plates and the heating elements, if necessary, in spite of the presence of a film formed by the sealing material. The surface irregularities of the heating elements can be natural and / or artificial. Indeed, the heating elements are in particular derived from a ceramic material with a positive temperature coefficient. Such heating elements 30 may be common commercial heating elements. As a result of their manufacture, such heating elements naturally have surface irregularities capable of accommodating a film of sealing material without affecting the quality of the electrical contact between the heating elements and the plates. In case of insufficiency, surface irregularities of the heating elements may be specifically provided during or after their manufacture. The heating elements are directly placed in contact with the plates according to their general plan of extension. The plates are heated uniformly over their entire surface facing one another by the heating elements interposed therebetween. For a given space requirement of the frame in its general plane, the heating body thus produced provides an optimization of the heating surface useful for raising the temperature of the air passing through the heating body.

The flow of air to be heated flows through the plates through the openings in a direction perpendicular to the general plane of the plates. The temperature rise of the plates is uniform and fast, with an optimized energy balance of the heating body. The heating capacity of the heating body can easily be adapted to lower costs according to the calories to be provided to increase the temperature of the air flow to be heated over a given heating period. Such an adaptation of the heating capacity of the heating body can be achieved by selecting the number of heating elements equipping the same heating unit and / or by selecting the number of heating assemblies 20 constituting the heating body. The heating body can be easily produced industrially. Indeed, the plates can be perforated by drilling or punching. Then the heating body can be made by successive removal of the plates and heating elements to form at least one said heating unit. The heating assembly can therefore constitute a monobloc heating unit made by joining the plates together. Such fastening can be effected by means of fasteners of the plates together, keeping the heating elements firmly fixed in the desired position between the plates. In order to limit the number of components forming the heating block, the plates can be secured to one another by means of the heating elements sealed to one and the other of the plates. Several heating assemblies may be formed successively in a direction substantially perpendicular to the overall plane of the chassis. Any of the plates of a first heater assembly may be operated to form any of the plates of a second heater assembly immediately adjacent to the first heater assembly. Several heating assemblies may be secured to each other by means of fasteners and / or via the heating elements as previously mentioned. Thus, several heating assemblies can form a unitary heating body that can be held on the chassis by said limited number of holding members. The heater can then be installed on the chassis by engaging the heater assembly with the retainers. Such engagement can be achieved by translation in the general plane of the heater assembly, following the overall plan of the chassis as referred to below. According to a non-limiting embodiment, the heating assembly comprising the plates and the heating elements is in one piece and can be held by the holding members, the heating assembly being positioned by translation along the overall plane of the frame since the any of its edges perpendicular to its so-called opposite edges.

According to a non-limiting embodiment, the heating elements are individually made of bodies derived from a material with a positive temperature coefficient, said bodies being of flat conformation being arranged in their general plane along the overall plane of the frame.

According to a nonlimiting embodiment, the perimeter of the constituent bodies of the heating elements is of curved conformation according to their general plan. According to a non-limiting embodiment, the heating block comprises several heating assemblies, the number of plates being greater than two and cooperating successively two by two to house groups of respective heating elements. The plates and the heating elements advantageously constitute a monoblock heating unit capable of being easily placed in engagement with the holding members. Such engagement between the heater assembly and the holding members can be easily accomplished by translating the heater assembly along the overall plane of the frame from any of its edges perpendicular to said opposed edges. Thus, the heating block consists of two unit blocks assembled to one another via the holding members. One of the unit blocks is formed of the frame incorporating the holding members, preferably formed slides. The other of the unit blocks is formed by at least one constituent heating unit of the heating body.

As previously mentioned, the heating elements are preferably individually constituted of bodies derived from a material with a positive temperature coefficient. Said bodies are more specifically planar conformation being arranged in their general plane in the overall plane of the frame. Thus, the surface of the heating elements used to heat the plates is the optimum surface of the heating elements arranged in the general plane of the plates. Preferably, the perimeter of the constituent bodies of the heating elements is of curved conformation according to their general plan, such as a circular or oval conformation. Thus, the effective area of the stones is optimized for a given size of the stones according to their general plan.

The heating body can easily have a plurality of heating assemblies to increase its heating capacity. The plates are in this case greater than two and successively cooperate in pairs to accommodate groups of respective heating elements.

To clarify such an arrangement of the heater, it is understood that the heater may have N heater assemblies formed from N groups of heating elements successively interposed between N + 1 plates. The heating body then advantageously constitutes a monobloc heating element 30 composed of a plurality of heating assemblies. It will be noted that a chassis may be of manufacture provided with holding members in plurality respectively assigned to the reception of several heating units. In this context, the holding members may be used in a number depending on the number of heating units required for a particular case of operation of the heating block. It results, for the same chassis, a modularity of the heating capacity of the heating block as needed from a selection of the number of heating units to be installed on the chassis. The present invention also relates to a method of manufacturing a heating block as just described. In general, the process of the present invention comprises the following operations for making the heater, for making the chassis, and for assembling them together. Considering the manufacture of the heating body, the following operations are carried out: a) arranging the openings through the plates, b) positioning the heating elements on a first plate and depositing a second plate superimposed on the first plate. The frame is then manufactured by forming it by molding and providing it with said holding members.

The preservation of the openings through the plates can be carried out by punching, in particular to preferably obtain the backs of material. The plates can be for this purpose brought to a workstation after cutting plates to one dimension and / or a desired conformation (s). One or more superimposed plates can be arranged at the workstation to arrange the openings to or through it. Alternatively, the plates can be fed as a strip of moving material to the workstation. In this case, the band is worked to preserve the openings, by punching in particular, and is cut to isolate a plate of the band. The tongue can be easily formed at one end of the plate when cutting the plate. The formation of the tongues is likely to be carried out indifferently beforehand, simultaneously or after the formation of the openings.

The removal of the heating elements can be easily achieved by group of heating elements. The manufacture of the heating block is finalized by installation of the heating body on the frame with a cooperation of the heating body and the holding members. According to a non-limiting embodiment, prior to the removal of the heating elements on the first plate, the method comprises an operation 10 of depositing on the plates of a sealing material at predefined locations for positioning the heating elements, the assembly heating composed of plates and heating elements then being rendered monobloc. It will be appreciated that alternatively, the sealing material could be deposited on the heating elements prior to pressing them into the predefined positioning locations. According to a non-limiting embodiment, the installation of the heating body on the frame is operated by translating the heating body along the frame 20 according to its overall plan, by introducing the edge of the slices of the plates inside the slides previously arranged along said opposite edges of the frame. According to a non-limiting embodiment, the manufacture of the heating body 25 comprises an additional operation of forming the tongues by cutting the plates. According to a non-limiting embodiment, the manufacturing operation of the heating body comprises the successive superposition removal of a plurality of plates in number greater than two, several groups of heating elements being respectively positioned in interposition between two plates successive. Considering the manufacture of the frame, the frame can be advantageously formed by molding and be provided with said holding members, preferably at the same time as molding or after its molding. Indeed, the frame may advantageously integrally mold the holding members, particularly in the advantageous case where the holding members are formed slides arranged along said two opposite edges of the frame. Such slides can also be formed along said opposite edges by grooving, especially in the case where the frame is for example formed by assembling profiles integrally with each other, such as in particular by gluing. In this case, the profiles can be previously grooved to form the slides.

Considering the finalization of the manufacture of the heating block, the heating body is installed on the frame by placing in cooperation between the heating body and the holding members. Such an installation is advantageously performed by translational sliding of the plates inside the slides 15 until the filling of the internal recess of the frame by the plates. For this purpose, the respective edges of the slices of two of their opposite edges are introduced and then slid inside the slides, applying a thrust against the plates in their general plane. More particularly, the installation of the heating element on the chassis is effected by translating the heating element along the chassis along its overall plane, by introducing the edge of the slices of the plates inside the slides previously provided along said opposite edges of the frame.

As previously mentioned, the heating element may consist of the superposition of two or more plates, and the manufacturing operation of such a heating body comprises in particular the successive superposition of a plurality of number greater than two, several groups of heating elements being respectively positioned in interposition between two successive plates. The present invention also relates to an electric heater for a ventilation system, heating and / or air conditioning of a motor vehicle, comprising a heating block as just mentioned. The electric radiator further comprises a connector for connecting the heating block to a source of electrical energy. According to a non-limiting embodiment, said connector comprises connectors cooperating by interlocking respectively with the tabs integrated in the plates, a first connector assigned to a plate of a heating assembly being connected to an electrically positive terminal and a second connector assigned to the other plate of the same heating unit being connected to an electrically negative terminal.

According to a non-limiting embodiment, the first connector is connected to the electrically positive terminal by means of a switch whose flip-flop is placed under the control of a means of control and / or control of the operation of the electric radiator. .

According to a non-limiting embodiment, the heating element is composed of at least two heating assemblies comprising generally three plates, a central plate interposed between two end plates is directly connected to the electrically negative terminal by means of a said second connector, said end plates being each connected to the electrically positive terminal by means of said respective first connectors via respective circuits each having a switch. According to a non-limiting embodiment, the switches are individually operable under the control means and / or control of the operation of the radiator, the heating capacity of the electric radiator being punctually adaptable depending on the individual actuation of the switches selectively by means of control and / or control of the operation of the electric radiator.

Other features, details and advantages of the invention will emerge more clearly on reading the description given below, by way of indication, of exemplary embodiments of the invention, in relation to the figures of the plates appended to FIG. which: FIG. 1 is a plan illustration of a heating block according to an exemplary embodiment of the present invention; - Figure 2 is an illustration in section along the edge of the heating block 5 shown in Figure 1; - Figure 3 is an illustration in section along the edge of a heating block according to a second embodiment of the present invention; FIG. 4 is a perspective illustration of a detail that can be applied both to the heating block of FIG. 1 or that of FIG. 3; FIG. 5 is a perspective detail of an exemplary embodiment of a frame that comprises a heating block according to the present invention; FIG. 6 is a plan illustration of an exemplary embodiment of a frame that comprises a heating block according to the present invention; and FIG. 7 is an exemplary embodiment of an electric heater 15 according to the present invention. It should first be noted that the figures show the present invention in detail and in particular ways of its implementation. Said figures and their description which will be made can of course serve, if necessary, to better define the present invention, both in its particularities and in its generality. Moreover, to clarify and make easy the reading of the description that will be made of the present invention, the common organs shown in the various figures are respectively identified in the descriptions of these figures with the same numbers and / or letters of reference without implying their individual representation in each of the figures and / or an identical arrangement of said common members between specific embodiments.

In FIG. 1 and FIG. 2, as well as in FIG. 3, a heating block 1 is organized to equip an electric radiator 2 as shown diagrammatically in FIG. 6. The electric radiator 2 is able to be installed inside of a pipe conveying a flow of air 3. Such a pipe is part of a ventilation, heating and / or air conditioning system of a motor vehicle. In this context, the air flow 3 may have to be heated and the electric radiator 2 may constitute a supplementary heating element and / or a main source of heat that can itself heat the air flow 3 and / or maintain it at a set temperature.

The heating block comprises a generally flat frame 4 arranged in a frame. Such a frame defined typically between peripheral edges, at least three in number, an inner recess. As a result, the frame 4 extends generally in an extension plane and has peripheral edges 5,5 ', 6 between which said inner recess extends. The internal recess of the frame 4 is intended to house a heating body 7. The heating body 7 comprises at least one heater assembly E1, E2 comprising plates 8,8 ', 8 "superimposed extending in their general plane 15 according to the overall plan of the chassis 4. Heaters 9 are interposed between the plates 8, 8 ', 8 "for their temperature rise. The plates 8, 8 ', 8 "are provided with perforations 10 to allow the passage of the air flow 3 through the heating body 7, the openings being separated from each other by a fraction of material of the corresponding plate. .

The air stream 3 is heated by the plates 8, 8 ', 8 "by being admitted inside the heating body 7, and discharged out of it, in a direction generally oriented perpendicular to the general plane of the plates 8,8 ', 8 ".

As an indication, the plates 8, 8 ', 8 "are of small thickness and can be assimilated to intrinsically rigid sheets, for example, plates having a thickness of between 0.4 mm and 1 mm (one millimeter), sufficient In order to control their flatness, the openings 10 are formed in particular through the plates 8, 8 ', 8 "by drilling or by punching.

The heating elements 9 individually consist of a positive temperature coefficient resistor. Each heating element 9 is formed of a generally flat unitary body, such as a ceramic body. Such a ceramic body is indicative of a thickness of between 1 mm (one millimeter) and 22 mm and 1.6 mm. The heating elements 9 are arranged in their general plane parallel to the general plane of the plates 8,8 ', 8 "being preferably of round or oval conformation as illustrated.

The heating elements 9 are arranged on the plates 8, 8 ', 8 "at predefined locations 11. Such locations 11 are provided by portions of material of the plates 8, 8', 8" free from perforations 10. Such locations 11 may be coated with a film of glue to attach the heating elements 9 to both plates 8,8 ', 8 ", so that a heating assembly E1, E2 can be made monoblock and be mounted on the chassis 4 in a single sliding operation of the heating unit E1, E2 monobloc inside retaining members 12,12 ', 12 "arranged in slideways. As shown in FIG. 3, in the case where the heating block 1 has several heating assemblies E1, E2 comprising a common median plate 8 ', such a heating block 1 can be introduced in a single sliding operation of heating block 1 inside the guides 12, 12 ', 12 ", particularly visible in FIG. 1, the openings 10 of the same plate 8, 8', 8" are arranged in staggered rows and distributed on the surface 8 ', 8' '. Particularly visible in FIGS. 2 and 3, the staggered arrangement of the openings 10 of a plate 8, 8', 8 "is offset in the general plane of the plates 8.8. 8 "relative to the staggered arrangement of the other plate 8, 8 ', 8" of the same heating assembly E1, E2.

Baffles are thus formed between the plates 8,8 ', 8 "to constrain the air flow 3 to lick the surface of the plates 8,8', 8" and thus optimize the heat exchange between the heater 7 and the flow of air 3. The passage of the air flow 3 through the heating body 7 is thus disturbed and promotes the transfer of heat 30 between the heating body 7 and the air flow 3. In the figure 1 and FIG. 2, the heating element 7 comprises two plates 8, 8 'forming a single heating assembly E1. In FIG. 3, the heating element 7 comprises three plates 8, 8', 8 ' a pair of heating assemblies E1, E2, a central plate 8 'is constituted by the two heating assemblies E1, E2, by cooperation respectively with two end plates 8, 8 "of the heating body 7.

Furthermore, as illustrated in FIG. 4, the openings 10 are preferably formed by the discharge of material 13 coming from the plates 8, 8 ', 8 "(the plate 8 has been illustrated in detail for greater visibility), such as Punching of such material 13 stiffens the plates 8,8 ', 8 "in their general plane and provide corridors 14 for channeling the flow of air 3. In the case where the heating body 7 comprises a only heater assembly El as illustrated in Figure 1 and Figure 2, the material discharges 13 of each of the plates 8,8 ', 8 "are oriented in opposite directions towards the outside of the heater body 7. On This ensures that the material discharges can not come into contact and bridge the two plates, in the event that the heating body 7 comprises at least two heating assemblies E1, E2. as shown in FIG. 3, the material discharges 13 are oriented s following the same direction of admission of the air flow 3 inside the heating body 7. This avoids ending up with material backs of two successive plates oriented towards each other and to present the risk to create a short circuit. In this case, it is notable that the material discharges 13 are preferably oriented towards the direction of admission of the air flow 3 inside the heating element 7. As previously mentioned, the plates 8, 8 ' 8 "are mounted on the frame 4 by means of holding members 12, 12 ', 12" arranged in slideways along two opposing edges 5, 5' of the frame 4. Such slides 12, 12 ', 12' are particularly illustrated in detail in Figure 5. The slides 12,12 ', 12 "are preferably formed along the opposite longitudinal edges 5,5' of the frame 4. It is understood that for each of the plates 8 , 8 ', 8 "that includes the heating body 7, the frame 4 comprises at least a pair of rails 12,12', 12" respectively formed on the same two opposite edges 5,5 'of the frame 4. Particularly visible on FIG. 2 and FIG. 3, the chassis 4 may also include auxiliary rails provided on the 3037867 n edge 6 of the frame 4 oriented perpendicularly to said opposite edges 5,5 'of the frame 4. In Figure 6, the frame 4 is incidentally provided with a reinforcement frame 15 composed of ribs arranged in longitudinal members and cross members. The frame 15 stiffens the frame 4 in its general plane, being disposed at least one of its large outer faces. As shown in the figure, it is sought a provision of the beams and sleepers as far as possible from the heating elements 9, so that the armature is not in line with 10 areas of high heat. Furthermore, the plates 8, 8 ', 8 "are advantageously derived from an electrically conductive material, such as copper or preferably less expensive aluminum.The plates 8, 8', 8" each comprise a tab 16 for their individual connection to a connector 17, 17 ', 17 "participating in a connection 18 of the electric heater 2, as illustrated in FIG. 7. The plates 8, 8', 8" thus constitute conduction members of an electric current from the tongue 16 which they are provided to the heating elements 9. In this context, the frame 4 is derived from an electrically insulating material, such as for example based on polyamide loaded with reinforcing fibers. And it is understood that the tabs 16 may, especially when the plates are made of aluminum, be provided with cuprous elements, respectively crimped around a tab.

In Figure 7, an electric heater 2 is equipped with a heating block 7 according to the present invention and said connector 18 providing the connection of the heating block 7 to a source of electrical energy 18 '. Such a source of electrical energy 18 'is in particular constituted by at least one battery equipping the motor vehicle. In this way, the connector 18 is connected to the on-board electrical network of the vehicle. The heating block 7 comprises, for example, two heating assemblies E1, E2, as shown in FIG. 3. The connector 18 comprises a set of connectors 17, 17 ', 17 "for connecting the heating block 7 to an electrical circuit 19. connectors 17, 17 ', 17 ", 3037867 are respectively engaged on a plate 8, 8', 8" which is assigned to them by means of the tongue 16 whose plates 8, 8 ', 8 "are respectively provided with . First 17.17 "connectors provide the respective connections of the 8.8" endplates to an electrically positive terminal 20 via switches 22, 22 '. The middle plate 8 'is connected directly to an electrically negative terminal 20' by means of a second connector 17 '. The switches 22, 22 'are respectively operable, individually or collectively, by a means 23 for controlling and controlling the operation of the electric radiator 2.

In an alternative embodiment not shown, a plate connected to an electrically positive terminal is cut to form a plurality of plate portions arranged facing a single plate connected to an electrically negative terminal. The heating elements are thus sandwiched between a positively electrically connected plate portion, specific to one or a first portion of the set of heating elements, and a negatively electrically connected plate, which is common to each heating element. And each positively electrically connected plate portion is connected to the network via a switch operable by a control means.

It is thus possible to control more finely the number of heated elements rendered active and the quantity of heat released as a function of the desired use of the associated electric radiator. This is particularly useful in the case of a heating block having only one heating unit.

The foregoing description aims to explain how the invention makes it possible to achieve the objectives it has set itself, and in particular to propose a heating block for an electric radiator which has good heating performance, while being particularly simple to produce. and to mount in an electric radiator. The use of metal plates to enclose the heating elements makes it possible to combine in one piece the electrical conduction functions for supplying the heating elements and the heat sink for heating the air flow therethrough. Moreover, the simplicity of manufacturing the perforated plates makes it possible to reduce the cost of obtaining these two functions, and it is therefore possible at equivalent cost to provide larger heating blocks. Of course, various modifications may be made by those skilled in the art to the structure of the heating block which has just been described by way of non-limiting example, in particular in the number of heating elements and in the form thereof. In any event, the invention can not be limited to the embodiment specifically described in this document, and extends in particular to all equivalent means and to any technically operating combination of these means.

Claims (20)

REVENDICATIONS1. Heating block (1) for an electric heater (2) of a ventilation, heating and / or air-conditioning system of a motor vehicle, the heating block (1) comprising at least one heating element (7) which comprises at least one heating element (9) and a frame (4) whose edges (5, 5 ', 6) delimit an internal recess in which the heating element (7) can be arranged, characterized in that the heating element (7) comprises at least one heating assembly (E1, E2) comprising at least two plates (8, 8 ', 8', 8 ") which comprises openings (10), and at least one heating element (9) arranged between the plates (8, 8 ', 8', 8 "). 2. heating block (1) according to claim 1, characterized in that the frame (4) comprises holding members (12, 12 ', 12 ") for maintaining the heating body (7) in the inner recess and holding the plates (8, 8 ', 8', 8 ") on the frame (4). Heating block (1) according to claim 2, characterized in that the holding members (12, 12 ', 12 ") hold the plates (8, 8', 8 ', 8") on the frame (4). such that these plates (8, 8 ', 8', 8 ") extend away from one another. 4. heating block (1) according to one of claims 2 or 3, characterized in that said holding members (12, 12 ', 12 ") are arranged on at least two opposite edges (5, 5') of the frame (4), these holding members (12, 12 ', 12 ") being engaged with the edge of the slices of the plates (8, 8', 8 ', 8"). Heating block (1) according to one of claims 2 to 4, characterized in that said holding members (12, 12 ', 12 ") are slideways arranged along at least two opposite edges (5, 5 ') of the frame (4), each of the opposite edges (5, 5') of the frame (4) having at least two respective rails (12, 12 ', 12 ") for receiving the plates (8, 8'; ', 8') through the edge of their edge. 6. heating block (1) according to claim 5, characterized in that the rails (12, 12 ', 12 ") extend in the thickness of the edges (5, 5', 6) of the frame (4). 5 7. heating block (1) according to one of the preceding claims, characterized in that the plates (8, 8 ', 8', 8 ") are made of an electrically conductive material. 8. Heating block (1) according to one of the preceding claims, characterized in that the plates (8, 8 ', 8', 8 ") each comprise at least one tab (16) forming an electrical connection member. 9. Heating block (1) according to any one of claims 1 to 8, characterized in that said openings (10) of a plate (8, 8 ', 8', 8 ") are arranged in staggered relation to each other. in the openings (10) of an adjacent plate (8, 8 ', 8', 8 "). Heating block (1) according to one of the preceding claims, characterized in that the plates (8, 8 ', 8', 8 ") each comprise portions of material comprising respective receiving locations (11). heating elements (9). 11. heating block (1) according to any one of the preceding claims, characterized in that the heating assembly (E1, E2) comprising the plates (8, 8 '; 8', 8 ") and the heating elements (9 ) is integral and able to be held by the holding members (12, 12 ', 12 "), the heating assembly (E1, E2) being positioned by translation along the overall plane of the frame (4) from one any of its edges (6) perpendicular to said opposite edges (5, 5 '). 12. A method of manufacturing a heating block (1) according to any one of claims 1 to 11, characterized in that the method comprises the following operations: *) manufacture the heating body (7) according to the following operations a) arrange the openings (10) through the plates (8, 8 ', 8', 8 "), b) position the heating elements (9) on a first plate (8, 8 ', 8', 3037867). 8 ") and deposit a second plate (8, 8 ', 8', 8") in superposition of the first plate (8, 8 ', 8', 8 "), *) manufacture the frame (4) forming it by molding and providing it with said holding members (12, 12 ', 12 "), 5 *) finalizing the manufacture of the heating block (1) by installing the heating element (7) on the frame (4) with a placing the heating body (7) in cooperation with the holding members (12, 12 ', 12 "). 13. A method according to claim 12, characterized in that prior to the removal of the heating elements (9) on the first plate (8, 8 ', 8', 8 "), the method comprises a removal operation on the plates. (8, 8 ', 8', 8 ") of a sealing material at predefined locations (11) for positioning the heating elements (9), the heating assembly (E1, E2) consisting of the plates (8, 8 8 ', 8 ") and heating elements (9) are then made monobloc. 14. Method according to any one of claims 12 and 13, characterized in that the installation of the heating body (7) on the frame (4) is operated by translation of the heating body (7) along the frame ( 4) according to its overall plan, by inserting the edge of the slices of the plates (8, 8 ', 8', 8 ") inside the sliders (12, 12 ', 12") previously arranged along said opposite edges (5,5 ') of the frame (4). 15. Method according to any one of claims 12 to 14, characterized in that the manufacturing operation of the heating body (7) comprises the removal 25 by successive superpositions of a plurality of plates (8, 8 '; ', 8' ') in number greater than two, several groups of heating elements (9) being respectively positioned in interposition between two successive plates (8, 8', 8 ', 8 "). 30 16. An electric radiator (2) for a ventilation, heating and / or air conditioning installation of a motor vehicle, comprising a heating block (7) according to any one of claims 1 to 11 and a connector (18) of connecting the heating block (1) to a source of electrical energy (18 '). 3037867 30 17. Electric radiator (2) according to claim 16, characterized in that the connector (18) comprises connectors (17,17 ', 17 ") cooperating by interlocking respectively with the tongues (16) integrated with the plates (8, 8 8 ', 8 "), a first connector (17, 17") assigned to a plate (8, 8 ") of a heater assembly (E1, E2) being connected to an electrically positive terminal (20) and a second connector (17 ') assigned to the other plate (8') of the same heater assembly (E1, E2) being connected to an electrically negative terminal (20 '). Electrical radiator (2) according to claim 17, characterized in that the first connector (17, 17 ") is connected to the electrically positive terminal (20) via a switch (22, 22 '). whose rocker is placed under the control of a means (23) for controlling and / or controlling the operation of the electric radiator (2). 19. Electric radiator (2) according to any one of claims 17 and 18, characterized in that the heating element (7) being composed of at least two heating assemblies (E1, E2) comprising generally three plates (8 , 8 ', 8 "), a center plate (8') interposed between two end plates (8,8") is directly connected to the electrically negative terminal (20 ') by means of a said second connector ( 17 '), said end plates (8,8 ") being each connected to the electrically positive terminal (20) by means of said respective first connectors (17,17") via respective circuits each having a switch (22,22 '). 25 20. Electric radiator (2) according to claim 19, characterized in that the switches (22,22 ') are individually operable under the control means (23) and / or control of the operation of the radiator, the heating capacity the electric radiator (2) being punctually adaptable according to the individual actuation of the switches (22,22 ') selectively by the means (23) for controlling and / or controlling the operation of the electric radiator (2).