WO2019158845A1

WO2019158845A1 - Frame for an electric heating device, comprising at least one device for retaining heating elements

Info

Publication number: WO2019158845A1
Application number: PCT/FR2019/050292
Authority: WO
Inventors: Frédéric PIERRON; Serif KARAASLAN; Pascal FOURGOUS; Yann COUAPEL; Romain DELCOURT; Laurent Tellier
Original assignee: Valeo Systemes Thermiques
Priority date: 2018-02-19
Filing date: 2019-02-11
Publication date: 2019-08-22
Also published as: FR3078147A1; FR3078147B1

Abstract

The invention relates to a frame (3) for an electric heating device (1) for heating an air flow circulating inside a ventilation, heating and/or air-conditioning system of a motor vehicle. The frame comprises at least one heating compartment (30) having at least one housing (7) intended to receive a heating element (5), said housing (7) being defined at least by two longitudinal walls (23, 25) defining vertically an insertion path for the heating element (5), and each longitudinal wall (23, 25) comprising an inner face (230, 250) oriented towards the insertion path. According to the invention, the frame (3) comprises at least one member for retaining the heating element (5) in position in the housing (7), said retaining member comprising at least one pin (4) configured to be inserted into a receiving hole (231) provided in one of the longitudinal walls (23, 25).

Description

FRAME FOR AN ELECTRIC HEATING DEVICE COMPRISING AT LEAST ONE DEVICE FOR MAINTAINING HEATING ELEMENTS

The invention relates to electric heating devices, especially for a heating, ventilation and / or air conditioning of a motor vehicle.

Heating of the air intended for heating the passenger compartment of a motor vehicle with a heat engine, as well as demisting and defrosting of the glazed surfaces, is ensured by heat exchange between a flow of air and a liquid of cooling of the heat engine circulating in a heat exchanger.

At the start of the engine and for a period of time following the start-up time, the calories carried by the engine coolant are insufficient to ensure rapid and efficient heating of the air to be blown into the passenger compartment. This is observed more particularly with certain types of engine and has a disadvantage in cold weather, because not only the internal temperature of the cabin can not be raised quickly, but also the defogging and de-icing functions can not be ensured effectively. .

To remedy these drawbacks, it has been proposed to mount an additional electrical heating device in the air flow directed towards the passenger compartment.

Such an additional electric heating device generally comprises a frame inside which are arranged a plurality of heating elements each arranged in a housing defined by walls of the frame. Each heating element, or heating rod, comprises parallel conductive plates between which heating resistive elements are mounted, for example positive temperature coefficient (PTC) resistors, and radiant elements attached to these conductive plates and increasing the surface area. heat exchange with the flow of air passing through the electric heater. Each heating element is inserted in a housing which is clean and then connected to an electrical connection element for supplying the heating resistive elements.

The sets of manufacture, on the one hand, the housings formed in the frame and, on the other hand, the heating elements, generate a set of mounting of each heating element which can be placed at a distance from the longitudinal walls delimiting the housing which 'accommodates, so that these heating elements can debate and generate noise when driving the vehicle.

To prevent the displacement of the heating elements, an electric heater frame may be provided with elastic holding means in position, which consist of tongues whose free end is arranged across the housing and the insertion path of the heating elements, this free end having a tendency to retract during the passage of the heating element, then to push this heating element against one of the walls housing to hold it in position by elastic return effect. These tongues are made integral with a wall defining the housing at one of their ends, they are free at the opposite end, and they have, in their original position, an arrangement such that the free end is disengaged from the wall defining the housing. This results in a fragility which can lead to the breakage of this elastic tongue and the loss of the function of holding in position of the heating elements.

An alternative is known in which the frame comprises means for plastic deformation of the heating elements, arranged projecting the walls participating in delimiting the housing in which the heating element is inserted. These plastic deformation means make it possible to plastically constrain and deform each heating element in the direction of the opposite wall of the housing, in particular during the insertion of the heating element into the housing. These plastic deformation means used to press the heating elements in the housing, while avoiding the presence of elastic elements exerting restoring forces on the heating elements, elastic elements that are likely to break. However, the insertion of the heating elements in the heating body being done by a robot, the meeting of the heating elements with the plastic deformation means has the consequence of considerably increasing the insertion forces. The sensors equipping the robot recurrently detect that the increase in insertion forces corresponds to an abutment of the heating elements in the heating body. For security reasons, this stop detection forces the robot to stop, so that verification by an operator is performed. Stopping the robot and checking by the operator interrupts the production line, which generates a waste of time and an additional manufacturing cost.

In this context, the invention aims to provide an alternative to existing solutions, alternative that allows a simple, effective, reliable and inexpensive maintenance of the heating elements in the context of the electric heating device.

The invention proposes for this purpose a frame of a device for electric heating of a flow of air flowing inside a ventilation, heating and / or air conditioning system of a motor vehicle, said frame comprising at least one heating compartment having at least one housing for receiving a heating element, the housing being defined at least by two longitudinal walls vertically defining an insertion path for the heating element, each longitudinal wall comprising an inner face oriented to the insertion path. According to the invention, the frame comprises at least one member for holding the heating element in position in the accommodation.

It should be understood here that the holding member is an independent element, reported in the frame according to the invention. It is therefore distinct from the longitudinal walls and the aforementioned insertion path. More specifically, the invention provides that the holding member comprises at least one pin configured to be inserted into a receiving orifice arranged in one of the aforementioned longitudinal walls. The pin is advantageously defined to extend at least partially inside the insertion path, and to be constrained by the heating element during its passage, and to exert a stress on this heating element once it placed in its housing, constraint to maintain said heating element in place in said housing.

Advantageously, the pin comprises a head intended to extend projecting inside the housing in which the heating element is received and a foot intended to be inserted into the receiving orifice arranged in the longitudinal wall defined above. More specifically, the head of the pin has a substantially planar face, arbitrarily designated in the following as the lower face, advantageously placed against the inner face of the longitudinal wall in which the receiving orifice is arranged once the pin installed in the latter. and it extends, within the housing in which the heating element is received, towards the other longitudinal wall which defines the housing. This direction, substantially perpendicular to the main direction of elongation of the longitudinal walls, or longitudinal direction will be, in what follows, designated as vertical direction.

Advantageously, the pin is made of a material chosen for its elastic properties, such that, under the effect of the force exerted by the heating element during its insertion, along the insertion path, in its housing , the head of the pin is elastically deformed, thus allowing the passage of said heating element without pulling the pin out of the aforementioned receiving orifice. By way of non-limiting example, the pin may be made by injecting, into a mold, an elastomer-type material. Once the heating element is put in place within its housing, the head of the peg, elastically deformed, then exerts, by an elastic return effect in its original position, a substantially vertical compressive stress on said element heating, maintaining it thus, especially in the vertical direction, within its dwelling.

According to one or more characteristics that can be taken alone or in combination, it can be provided that:

- The receiving port of the pin passes right through the longitudinal wall in which it is arranged, that is to say it extends from one side to the other of the wall in the vertical direction previously defined. In other words, the foot of the pawn extends over the entire thickness of the longitudinal wall in which is arranged the aforementioned receiving orifice, and it opens, on the one hand, at the inner face, previously defined, of this wall and, on the other hand, at the opposite outer face to the inner face and parallel to it, the same wall.

- The shapes and dimensions of the foot of the pawn are defined complementary to those of the aforementioned receiving orifice. More specifically, the shapes and dimensions of the foot of the pin are defined, taking into account the manufacturing tolerances of said foot and manufacturing tolerances of the previously defined receiving orifice, so that the foot of the pin can be inserted easily into the receiving port, but without excessive play. In particular, the respective shapes and dimensions of the foot of the pin and the receiving orifice are defined in such a way that the extraction of the pin from this orifice can only result from a voluntary maneuver and from a force of one operator.

- The foot of the pin has at least one axis of symmetry coincident, when the pin is inserted into the previously defined receiving hole, with a vertical axis of symmetry of said receiving orifice. Advantageously, the dimension, in the direction of this vertical axis of symmetry, of the foot of the pin, is substantially equal to that of the receiving orifice. In other words, when the pin is inserted into its receiving hole, the foot of the pin is flush with the hole through which the receiving orifice opens into the inner face of the corresponding longitudinal wall, and it also outcrops the hole through which this reception opening opens into the outer face of said wall.

- The vertical axis of symmetry of the foot of the pawn is also axis of symmetry of the pawn head.

- The length of the head of the pin, defined as the dimension of this head in the longitudinal direction defined above, is greater than the longitudinal dimension of the receiving orifice. More specifically, the edges of the head of the pin protrude from the edges delimiting the hole through which the receiving orifice opens into the internal face of the longitudinal wall in which it is arranged. In other words, the surface of the lower face of the head of the pin is greater than the surface of this hole.

- The thickness of the head of the pin, that is to say its dimension in the vertical direction defined above, is maximum to the right of the receiving orifice and decreases towards the periphery of said head. According to a particularly advantageous embodiment, but not exclusive, of the invention, the head of the pin has substantially the profile of a sphere portion. Alternatively, it has a substantially frustoconical profile whose largest diameter is formed by the edges of the lower face of this head. In other words, the head of the pin has, in particular in the longitudinal direction defined above, a vertically inclined profile. It should be noted here that if a head having a form of revolution has low manufacturing costs, such a shape is not exclusive and any other form can be envisaged for the head of the pawn forming the organ of maintenance.

- The pin has a base which extends in the extension of the foot of the pin, projecting from the foot opposite the head of the pin in the vertical direction defined above. In other words, the head of the pin projecting from the inner face of one of the longitudinal walls which delimits the housing in which the heating element is received, the base of the pin protrudes from the outer face of this longitudinal wall, the outer face being defined here, as a reminder, as the face of this longitudinal wall parallel to the inner face and opposite thereto.

- The vertical axis of symmetry, previously defined, the foot of the pawn, is also vertical axis of symmetry for the base of the pawn.

- The edges of the base of the pin protrude from the walls that define the receiving orifice. It should be understood here that the base of the pin has a substantially flat face, hereinafter referred to as the upper face, configured to be placed in contact with the outer face of the longitudinal wall which defines the housing in which the heating element is received. when the pin is inserted into its receiving hole. In other words, the surface of the upper face of the base of the pin is greater than the surface of the hole through which the receiving orifice opens into the outer face of the longitudinal wall in which said receiving orifice is arranged.

- The thickness of the base of the pin, that is to say its dimension in the vertical direction defined above, is maximum with respect to the receiving orifice and decreases towards the periphery of said base. According to a particularly advantageous embodiment, but not exclusive, of the invention, the base of the pin forming the holding member has substantially the shape of a portion of spb era. Alternatively, it has a frustoconical profile whose largest diameter is formed by the edges of the upper face of this base. In other words, the base of the pin has, in particular in the longitudinal direction defined above, a vertically inclined profile. It should be noted here that if a base having a form of revolution has low manufacturing costs, such a shape is not exclusive and any other form can be envisaged for the base of the pin forming the holding member.

- The dimension, in particular longitudinal, of the base of the pin is substantially smaller than the dimension, in particular longitudinal, of the head of this pin. Advantageously, the same applies to the dimension of the base in the direction which defines, with the aforementioned longitudinal direction, the planes of the longitudinal walls which delimit the housing in which the heating element is received in the frame according to the invention. In other words, the surface of the upper face of the base of the pin is less than the surface of the underside of the head of the pin. - The foot of the pin has an opening configured to allow deformation, in particular longitudinal, said foot during its insertion into the receiving orifice arranged in the longitudinal wall of the frame according to the invention. Advantageously, the vertical axis of symmetry of the head, the base and the foot of the pin, is also vertical axis of symmetry for this opening. Advantageously, this opening crosses the entire base of the pin in the vertical direction defined above, and it extends, along the same vertical direction, on all or part of the foot of the pin. In other words, this opening opens into an outlet port at the vertical end of the base of the pin. This opening allows the establishment of the pin in the previously defined receiving orifice. Indeed, thanks to the elasticity of the material which constitutes the pawn, the operator can exert, on the base of the pawn, a pressure aiming to bring closer to the vertical axis of symmetry of the pawn the walls which delimit this opening. It follows that the foot of the pawn and its base are deformed in such a way that the dimensions, perpendicular to the vertical direction, of the base of the pion diminish. Thanks to its inclined profile, it is then possible to insert the base of this pin into the previously defined receiving hole. Given the respective dimensions of the foot and the base of the pin, once the pin is inserted into this hole so that the underside of its head bears against the inner face of the longitudinal wall in which is arranged l the receiving orifice, the edges of the upper face of the base of the pin have crossed the edges of the hole through which the receiving orifice opens into the outer face of the longitudinal wall. The walls of the pawn foot and the base which delimit the aforesaid opening then return elastically to their initial position, and the pin is then blocked by a form of locking within the receiving orifice, the upper face of the base of the pin being placed against the outer face of the longitudinal wall which defines the housing in which the heating element is received. In other words, the longitudinal wall in which the receiving orifice of the aforementioned pin is arranged is then sandwiched or sandwiched between the head of this pin and the base thereof, more precisely between the lower face. of the pawn's head and the upper face of the base of it.

- The pin extends over the entire transverse dimension of the longitudinal wall in which is arranged the receiving orifice. The width is here defined as being the dimension in the direction, here transversal, which, along with the longitudinal direction, defines the longitudinal walls which delimit the housing in which the heating element is received. In the heating device in which is placed the frame object of the invention, it is also the direction followed by the flow that passes through the heating device to be heated. According to this embodiment variant, the head of the peg therefore substantially forms a bead which extends projecting towards the inside of the housing in which the heating element is received, substantially over the entire width of the longitudinal wall in question. Such a configuration makes it possible, in particular, to distribute over the entire width of this longitudinal wall, the compressive stress that the pin and, more specifically, its head, exerts. on the heating element once it is put in place in its housing frame according to the invention. Another advantage of such a configuration is that, by increasing the surface of the lower face of the head of the pin, it limits the risk of tearing of the latter from the receiving orifice during the insertion of the element. heating. It should however be noted that, in such a configuration, the receiving orifice will advantageously not extend, for its part, over the entire width of the longitudinal wall, in order to avoid weakening it by the arrangement of a slot on all of one of its dimensions.

- The same longitudinal wall comprises at least two receiving holes arranged successively in the insertion path, each intended to receive a pin as previously described.

- At least one receiving orifice is formed in the vicinity of a bottom wall participating to delimit each housing with the longitudinal walls.

- The frame has a plurality of receiving orifices and associated pins formed in the same housing, the pins having heights greater and greater in the direction of insertion of the heating element in the housing.

The invention also relates to an electric heating device comprising at least one heating element and a frame defining at least one housing for receiving the heating element, characterized in that the frame is as previously defined and in that the at least one heating element is held in position in the corresponding housing by a vertical compression stress generated by at least one pin inserted into a receiving orifice arranged in one of the longitudinal walls which delimit the housing in which the heating element is received.

Other features and advantages of the present invention will emerge more clearly from the description and the drawings, among which:

FIG. 1 is a front view of an electric heating device according to a first embodiment of the invention, comprising a frame in which three heating elements have been inserted and at one end of which is fixed an electrical connection interface. , the heating elements being separated from each other by an air passage zone formed of a perforated plate;

FIG. 2 is a perspective view of a detail of the frame of FIG. 1, without one of the heating elements, so as to make visible various parts of this frame and of the insertion path of a heating element in FIG. within it, FIG. 3 is a sectional view of a detail of the longitudinal wall of the frame illustrated in FIG. 1, without a heating element so as to make visible a first variant of a member for holding the heating elements;

FIG. 4 is a diagrammatic sectional view of the pin forming the holding member of FIG.

- And Figure 5 is a schematic perspective view of one of the longitudinal walls of the frame shown in Figure 3, without heating element so as to make visible a second variant of the pin of a holding member of these heating elements.

It should first be noted that if the figures set forth the invention in detail for its implementation, said figures can of course be used to better define the invention where appropriate. However, it should be noted that these figures only show part of the possible embodiments of the invention.

In the description which follows, reference will be made to an orientation as a function of the longitudinal axes L, vertical V and transverse T, as defined by the trihedron L, V, T shown in the figures. The longitudinal axis L corresponds to the elongation direction of the frame of the electric heating device, the transverse axis T perpendicular to the longitudinal axis L, corresponds to the direction followed by the flow of air to be heated through the device. heating, and the vertical axis V is perpendicular to both the longitudinal axis L and the transverse axis T. It should be noted that the choice of designations of these axes is not limiting the orientation that can take the electric heater in its application to a motor vehicle.

With reference to FIGS. 1 and 2, an electric heating device 1 according to the invention comprises a frame 3 in which heating elements 5, capable of transforming an electric current into thermal energy, can be inserted. To ensure the position of the heating elements 5 once they are inserted into their respective housings, the frame 3 comprises various holding devices which will be described in detail below.

The electric heating device 1 is intended to be housed in an air circulation duct of a ventilation, heating and / or air conditioning system, so as to transform the electrical energy taken from the vehicle into thermal energy restored. in the air passing through this duct. The installation is not shown here, but it will be understood that a main conduit of this installation conventionally comprises an opening made in one of its walls for the insertion of the electric heating device. Advantageously, the heating elements 5 comprise means capable of exchanging heat, such as radiant elements 53 making it possible to increase the heat exchange surface, with the flow of air passing through the electric heating device 1. The heating elements 5 also comprise electrodes 54 between which heating resistive elements are arranged, for example resistors with a positive temperature coefficient 55 (PTC), and against which the radiant elements 53 are fixed. · The electrodes 54 and the PTC resistors 55 make it possible to transform an electric current in thermal energy to be transferred to the airflow passing through the electric heater. It should be noted that the resistors with positive temperature coefficient 55 can be glued directly on the radiant elements 53

The frame 3 comprises a heating compartment 30, forming a receiving housing for the heating elements 5, and a connection interface 100 formed at one of its ends. The heating elements 5 are inserted into housings 7 formed inside the heating compartment 30. It will be understood that the connection interface 100 closes an access through which the heating elements 5 are inserted in the compartments 7 of the heating compartment. At the same time as it allows the connection of the electric heating device 1 to an electrical network of the vehicle allowing the electric supply of the heating elements 5

The frame 3 and the heating compartment 30 have the general shape of a rectangular parallelepiped. The two main faces of the frame 3, respectively arbitrarily designated as the front face 30a and the rear face 30b (the rear face 30b is not visible in the figures), opposite along the transverse axis T, are perforated to allow the passage of the flow of air to be heated and heat diffusion in the conduit where the electric heater 1 is installed. The frame 3 comprises a median plane corresponding to a plane passing through one half of the frame and being perpendicular to the transverse direction followed by the flow of air flowing through the electric heating device.

1. It is understood that the front 30a and rear 30b of the frame 3 extend in planes parallel to the median plane. It is also understood that the terms "front" and "rear" are purely arbitrary and in no way prejudge the orientation of the frame 3 within the motor vehicle in which the heating device 1 is placed.

In the embodiment illustrated in Figures 1 and 2, it is also noted that the frame 3 comprises perforated plates 9 arranged between each housing 7 and extending in the median plane of the frame 3 · These perforated plates 9 participate in the rigidification of the frame 3 and form air passage zones. In the example, non-exclusive, more particularly illustrated by FIGS.

2, the perforated plates 9 take the form of bars comprising ventilation slots 90 allowing the flow of air to flow through, the ventilation slots 90 being positioned one after the other along the longitudinal axis L of the heating device 1. It will be understood that the plates perforations 9 may take the form of perforated plates of holes of circular section without departing from the context of the invention.

The housings 7 of the frame 3 are defined in particular by longitudinal walls 23, 25 extending along the longitudinal axis L. More specifically, the housing is defined by two longitudinal walls 23, 25, including a first longitudinal wall 23 and a second one. longitudinal wall 25 delimiting vertically an insertion guide 26 for the heating element 5 · The insertion path 26 is the path taken by the heating element 5 when it is inserted into the housing 7. In other words, the insertion path 26 corresponds to a volume occupied by the heating element 5 during its insertion. Thus, the spacing between the first longitudinal wall 23 and the second longitudinal wall 25 of the same housing 7 corresponds to the vertical dimension of the heating element 5, the manufacturing clearance. According to the embodiment illustrated in Figures 1 and 2, the frame 3 comprises three housings 7 with a central housing and two lateral housing located on either side of the central housing.

Each longitudinal wall 23, 25 comprises an inner face 230a, 250a oriented towards the insertion path 26, and an outer face, 230b, 250b, parallel to the corresponding inner face 230a, 250a and opposite thereto according to the direction of the vertical axis V. The inner and outer faces of the same wall are delimited by two end edges 23a, 23b, 25a, 25b extending longitudinally. For the first longitudinal wall 23, there is defined a first end edge 23a located opposite a second end edge 23b (see Figure 2). Similarly, for the second longitudinal wall 25, a first end edge 25a located opposite a second end edge 25b, not visible in FIG. 2, is defined.

Each housing 7 is delimited, moreover, by a bottom wall 21. This bottom wall 21 is located opposite an opening 50 (see Figure 1) by which the heating elements 5 enter the heating compartment. 30, and which is intended to be covered by the connection interface 100. It should be noted that the heating elements 5 are inserted into the housings 7 in a direction of insertion parallel to the longitudinal axis L, the direction of insertion being defined from the opening 50 to the bottom wall 21.

Ending elements 210 may extend from the bottom wall 21, towards the opening 50. In other words, each abutment element 210 extends along the longitudinal axis L towards the Inside the housing 7 · Two abutment elements 210 may be provided per housing 7 · In general, the number of abutment elements 210 in a housing 7 is equal to the number of radiating elements 53 equipping the element heater 5 intended to enter this dwelling 7 · The frame 3 also comprises ribs 6, 8 delimiting transversely the insertion path of the heating element 5. For this, the ribs extend in a plane defined by the vertical axis V and the longitudinal axis L, also called vertical longitudinal plane, perpendicular to the longitudinal walls 23, 25. Among these ribs, there are ribs extending partially between two longitudinal walls 23, 25 forming the same housing 7, called guide ribs 6 in the following description, and ribs extending at least between two longitudinal walls 23, 25 forming the same housing 7, called stiffening ribs 8. The spacing between two ribs, whether of guiding or stiffening, located on both sides other of the insertion path 26 along the transverse axis T, corresponds to the transverse dimension of the heating element 5, to the manufacturing clearance.

The stiffening ribs 8 connecting the two longitudinal walls 23, 25 participate in the stiffening of the frame 3 and the heating compartment 30. According to the embodiment illustrated in Figures 1 and 2, the guide ribs 6 and the ribs stiffening 8 extend from an end edge 23a, 23b, 25a, 25b of the inner faces 230a, 250a, and projecting from the corresponding inner face.

According to the invention, and in order to ensure the holding in position of each heating element 5 inside its housing 7 between the longitudinal walls 23, 25 participating in delimiting the housing 7, the frame 3 comprises, as it has previously specified, at least one holding member configured to extend at least partially across the housing 7 so as to be on the passage of the heating element 5 during its insertion. More specifically, the frame 3 according to the invention comprises at least as many holding members as it comprises of housings 7 for receiving a heating element 5 · In the following, or the holding members intended to equip a single housing 7 will be more precisely described, it being understood that the same description can be applied to all of the holding members intended to equip all the housing 7 of the frame 3 and the heating device 1 according to the invention.

FIG. 3 illustrates, in section along a plane parallel to the previously defined vertical longitudinal plane, a portion of a housing 7 delimited vertically by the first longitudinal wall 23 and the second longitudinal wall 25. According to the invention, the maintenance is a pin 4 configured to be inserted into a receiving orifice 231 arranged in one of the longitudinal walls delimiting the housing, here the first longitudinal wall 23.

With reference to this FIG. 3 and to FIG. 4 on which the pin is illustrated alone, the pin 4 comprises a head 40 which protrudes inside the housing 7 when the pin is secured to the corresponding longitudinal wall. , as well as a foot 41 which is configured to be placed in the receiving orifice 231 arranged in the longitudinal wall 23 and which is configured to lock the pin in position relative to the frame.

Advantageously, this pin is made in one piece, the head and the foot forming a single piece. The pin is, for example, made by injecting, in a mold, a material chosen for its deformation properties both elastic and plastic. By way of non-limiting example, the pin 4 may be made of a material of the family of elastomers.

The receiving orifice 231 here extends over the entire vertical dimension, or height, of the first longitudinal wall 23 in which it is arranged. In other words, the receiving orifice 231 extends from the inner face 230a of this first longitudinal wall 23 to the outer face 230b of the same longitudinal wall, so as to open in each of them. The receiving orifice 231 thus forms a duct which passes vertically through the longitudinal wall 23. According to the particularly advantageous embodiment, but not exclusively, illustrated by FIGS. 3 and 4, the receiving orifice 231 has an axis of symmetry Y substantially parallel, with manufacturing tolerances, to the vertical axis V previously defined. According to various alternative embodiments, the receiving orifice 231 may be cylindrical with a Y axis, or it may be in the form of a slot extending in a transverse direction, parallel to that of the transverse axis T previously defined, from one end edge to the other.

The head 40 of the pin 4 has a substantially planar face 400 projecting from which extends the foot 4L In the following, this substantially planar face 400 of the head 40 of the pin 4 will be arbitrarily designated as the lower face 400 of the head 40 of the pin 4 being understood that the term "lower" in no way prejudices the orientation of the pin 4 and / or the frame 3 in the motor vehicle in which the heater 1 is installed.

This substantially planar face 400 is intended to be placed against the inner face 230a of the longitudinal wall 23 when the foot 41 of the pin 4 is housed in the receiving orifice 23L forming a stop surface at the depression of the pin in this receiving orifice. To do this, it is understood that the lower face 400 of the head 40 of the pin 4 extends so as to at least cover the surface of the receiving orifice 23L so that the peripheral edges of the lower face 400 of the head 40 of the pin 4 come against the inner face 230a of the first longitudinal wall 23 around the edges defining the receiving orifice 231 on the first longitudinal wall.

The head of the pin has a convex shape which extends, from its lower face 400, in the direction of the vertical axis V, towards the second longitudinal wall 25 which delimits, with the first longitudinal wall 23, the housing 7 in which the heating element 5 is received. The head 40 of the pin 4 thus extends vertically within the housing 7 and the insertion path 26. In in other words, the head 40 of the pin 4 thus constitutes an obstacle to the insertion of the heating element 5 in the longitudinal direction L within the insertion path 26.

Advantageously, the head 40 of the pin 4 has an axis of symmetry Y1 substantially coincidental, when the pin 4 is inserted into the receiving orifice 231, with the axis of symmetry Y of the latter. Furthermore, according to the non-exclusive exemplary embodiment, more particularly illustrated in FIGS. 3 and 4, the shape, from its lower face 400, of the head 40 of the pin 4, is substantially that of a portion of sphere centered on this axis of symmetry Yl. In a more general manner, the dimension, in the direction of the vertical axis V, of the head 40 of the pin 4, is maximum on the axis of symmetry Y of this head, and it decreases towards the edges of this head. this. According to other exemplary embodiments, not shown, the head 40 of the pin 4 may have a substantially frustoconical profile from its lower face 400, frustoconical profile whose largest diameter is materialized by the peripheral edges of said lower face 400. In other words, the head 40 of the pin 4 forms, in the longitudinal direction L of insertion of the heating element 5 in the housing 7, a surface inclined from the internal face 230a of the longitudinal wall 23, direction of the second longitudinal wall

25-

As previously stated, the foot 41 of the pin 4 is configured to fit into the receiving orifice 231. In other words, the shapes and dimensions of the foot 41 of the pin 4 are defined complementary to those of the orifice 231, so that the foot 41 of the pin 4 can be easily inserted, but without excessive play, within the receiving orifice 231. In the illustrated example, in which the receiving orifice has a shape cylindrical axis Y, the foot 41 of the pin 4 has a cylindrical barrel shape, which may have a diameter slightly greater than the diameter of the receiving orifice, so that it is necessary to press force the foot of the pawn in the receiving hole.

The foot 41 is attached to the head 40 of the pin 4, more precisely to the lower face 400 thereof, at one of its ends in the vertical direction V, and it has in the illustrated example a base 42 to the opposite end. Advantageously, the dimension, in the direction of the vertical axis V, of the foot 41 of the pin 4, is defined in such a way that, when this foot 41 is inserted into the receiving orifice 231, on the one hand, the face 400 of the head 40 of the pin 4 is placed against the inner face 230a of the longitudinal wall 23 and, secondly, the end of the foot 41 opposite the end by which it is attached to the head 40 is flush with the outer face 230b of the longitudinal wall 23. Arbitrarily, in what follows, the end of the foot 4b in the vertical direction V, by which the foot 41 is attached to the lower face 400 of the head 40 of the pin 4 will be designated as the upper end 410a, and the opposite end of the foot 41 in the same vertical direction V will be designated as the lower end 410b. It goes without saying that these denominations are arbitrarily chosen according to the orientation of the pin 4 on the representations made of the different figures and that they do not prejudge in any way the orientation and the disposition of the pin 4 and the frame 3 in the equipped motor vehicle of the heater 1.

Advantageously, the vertical axis of symmetry Y1 of the head 40 of the pin 4 is also axis of symmetry for the foot 41 of the pin 4 · According to various non-limiting exemplary embodiments, the foot 41 of the pin 4 may be cylindrical with a pin Yl, or it may be in the form of a rib lengthening at a time in a vertical direction parallel to that of the vertical axis V previously defined and in a transverse direction parallel to that of the transverse axis T.

When the heating element 5 is inserted, in the longitudinal direction L, in the housing 7, along the insertion path 26, its front end, that is to say the first of its ends to be inserted into the housing 7, first abuts against the head 40 of the pin 4 · It is then necessary to exert a longitudinal stress to allow the crossing, by the heating element 5, the vertical obstacle that constitutes the head 40 of the Pion 4 on the insertion path 26. The inclined shape of this head according to, in particular, the longitudinal direction, facilitates this crossing, while limiting the risk of tearing of the pin 4 and driving it in the longitudinal sliding movement of the heating element 5 · The capacity of elastic deformation of the material chosen to make the pin 4 also facilitates this crossing.

Once crossed the obstacle formed by the head 40 of the pin 4 within the housing 7, the heating element 5 is sandwiched between the second longitudinal wall 25 and the head 40 of the pin 4 · The elastic properties of the material which constitutes this head 40 force the head to resume its original position and thus to exert a vertical stress on the heating element 5, maintaining the latter in this vertical direction within the housing 7, it being understood that the maintenance of the heating element in the transverse direction is ensured by the respectively guiding and stiffening ribs 6, 8, previously defined, against which the heating element slides longitudinally during its insertion along the insertion path 26.

In order to further reduce the risks of tearing off the peg 4 and driving it out of the receiving orifice 231 during the longitudinal sliding insertion of the heating element 5 along the insertion path 26, the pin 4 comprises a base 42 configured so that, when the pin 4 is secured to the corresponding longitudinal wall by cooperation of the foot 41 in the receiving orifice 23L longitudinal wall 23 is sandwiched or sandwiched between this base 42 and the head 40 of the pawn 4 ·

The base 42 of the pin 4 extends, from the lower end 410b of the foot 4L, that is to say the end opposite the head 40, extending this foot 41 as transversely as longitudinally. More particularly, as illustrated in FIGS. 3 and 4, the base 42 comprises a face 420 extending perpendicularly to the lower end 4'0b of the foot 4L, the face 420 being advantageously flat so as to be placed against the external face 230b of the longitudinal wall 23 when the pin 4 is inserted into the receiving orifice 23L arbitrarily, this face 420 will be designated in the following as the upper face 420 of the base 42, it being understood that this term is arbitrary and that it does not prejudge nothing of the orientation of the base 42 and the pin 4 within the frame 3 in the motor vehicle equipped with the heating device 1. It follows from the foregoing that the upper face 420 of the base 42 and the lower face 400 of the head 40 are parallel or substantially parallel to each other.

The base 42 has a symmetry along the vertical axis of symmetry Yl of the pin 4 · According to various embodiments, the base 42 of the pin 4 may or may not present a symmetry of revolution about this vertical axis Yl.

Furthermore, in this illustrated embodiment, the base 42 of the pin 4 has a substantially frustoconical shape whose largest diameter is, in the vertical direction, at the upper face 420 of the base 42. Alternatively, the base 42 may, by way of non-limiting example, have the shape of a sphere portion centered on the vertical axis of symmetry Y1 of the pin 4. In general, the dimension, in the vertical direction V, of the base 42, is advantageously maximum at the upper face 420, and it gradually decreases towards the free end of the base 42, so that the base 42 of the pin 4 has in the longitudinal direction L an inclined ramp profile .

The pin 4 further comprises an opening 43 which extends from the lower end 421 of the base 42 opposite, in the vertical direction T, at the end by which this base is attached to the foot 4 In other In other words, this lower end 421 corresponds to the free end of the base. The opening 43 extends, in the vertical direction V, from the face defining the lower end 421 of the base 42, towards the head 40 of the pin 4, at least through the base 42 and in the illustrated case. through the foot 41 in the continuity. Advantageously, the vertical axis of symmetry Y1 of the foot 4L of the head 40 and the base 42 of the pin 4 is also axis of symmetry for the opening 43. According to various embodiments of the invention, which are not limiting, the opening 43 may be cylindrical axis Yl, or it may have any other shape. According to the embodiment more particularly illustrated in FIGS. 3 and 4, the opening 43 is delimited, in the vertical direction V, by a bottom wall 430, substantially parallel to the upper face 420 of the base 42 and to the lower face 400 of the head 40 of the pin 4

The combination of the material with elastic properties used for the design of the pawn 4, and in particular of the base 42, and the presence of this opening 43 allows an elastic deformation of the base and in particular a rapprocbement of the edges of this base to reduce the overall dimensions and allow the insertion of the base in the receiving orifice as will now be described.

The insertion of the pin 4 into the receiving orifice 231 is as follows. The base 42 arranged projecting from the foot 41 of the pin 4 is first presented in front of the receiving orifice 23L more precisely on the side of the internal face 230a of the longitudinal wall 23 in which this receiving orifice is arranged. More specifically, given the respective dimensions, in particular along the longitudinal direction L, of the receiving orifice 231 and the base 42, the inclined walls of this base 42 are then placed against the edges delimiting the hole 231a by which the 231 receiving orifice opens into the inner face 230a of the longitudinal wall 23. When the operator exerts, on the pin 4, a force in a direction illustrated by the arrow F in Figure 3, parallel to the vertical direction V, to insert the pin 4 in the receiving orifice 23L the particular profile of the base 42, combined with the properties, in particular the elastic properties, of the material used to make the pin 4, lead to a deformation of the base 42 whose lower end 421 can then engage at least partially in the conduit formed by the receiving orifice 231 in the thickness of the longitudinal wall 23. The inclined ramp profile that this base pe Remains to continue the insertion of the pin through the longitudinal wall with less effort to provide by the operator. The presence of the opening 43, combined with the elastic properties of the material used to make the pin 4, leads to additional deformation of the base 42 and, in particular, to a closer relationship to the vertical axis of symmetry Y1 of the pin 4, walls which delimit, along the vertical direction V, the opening 43 and, therefore, to a form of tightening of the base 42 of the pin 4 about the vertical axis of symmetry Y1 thereof, and the case appropriate to a form of tightening the foot 41 of the pin around the same axis Yl. It follows that it becomes possible to insert the entire base 42, deformed, within the receiving orifice 23L and until the edges of the upper face 420 thereof have crossed. the edges of the hole 23lb through which the receiving orifice 231 opens into the outer face 230b of the longitudinal wall 23. Free from the stresses exerted, in particular along the longitudinal direction L, by the walls which define the receiving orifice 23L the base 42 and the opening 43 then elastically return, thanks to the mechanical properties of the material bboisi to achieve the pin 4, their original shapes and dimensions. It then results from the dimensions, in particular along the vertical direction V, of the foot 4L and the dimensions, in particular along the longitudinal direction L, of the head 40 and of the base 42 of the pin 4, that the longitudinal wall 23 is then taken up. sandwiched between the lower face 400 of the head 40 and the upper face 420 of the base 42 of the pin 4 · The latter is thus blocked, in the vertical direction V, in the receiving orifice 23L which further reduces the risks of when the insertion, along the insertion path 26, of the element heating 5 in the dwelling 7 ·

In the above, the pin 4 has been described by its characteristics in particular in the vertical directions V and longitudinal L of the trihedron L, V, T, previously defined. According to the embodiments of the invention in which the pin 4 has a symmetry of revolution about its vertical axis of symmetry Yl, the characteristics and features that the pin 4 has in the longitudinal direction L can be transposed in a similar manner to the transverse direction T. According to the embodiments which have just been described and which are illustrated in FIGS. 3 and 4, it should be noted that the pin 4 has a dimension in the transverse direction T defined above which is less than the dimension in the same direction of the longitudinal wall 23 in which the receiving orifice 231 is arranged.

Figure 5 shows an alternative embodiment of the invention. With reference to this figure, the head 40 of pin 4 extends over the entire width, that is to say the dimension, in the transverse direction T, of the longitudinal wall 23. The pin 4 here has a plane of symmetry substantially parallel to both the transverse axis T and the vertical axis V, and containing the previously defined axis of symmetry Y1. The head 40 then forms a bead that extends vertically across the insertion path 26 and the longitudinal wall 23, perpendicular to the longitudinal wall 23. It should be noted that, in this case, the receiving orifice 231 advantageously takes the form of a slot arranged, in the transverse direction T, over a major part of the longitudinal wall 23. However, in order to avoid any excessive embrittlement of the latter, this slot will advantageously only partially extend over the transverse dimension of this longitudinal wall 23. Similarly, in this case, the foot 41 of the pin 4 will advantageously be in the form of a rib configured to fit into the slot formed by the receiving orifice 231.

Such a configuration makes it possible to further reduce the risks of tearing the peg 4 out of the longitudinal wall 23 during the positioning of the heating element 5 along the insertion path 26. Indeed, the head 40 of the peg 4 having a larger volume, the longitudinal stress to exert to "take off" the lower face 400 of the head of the inner face 230a of the longitudinal wall 23 against which it is plated, when the pin 4 is inserted into the hole of 23L reception will be greater than in a configuration in which the volume occupied by the head 40 on the longitudinal wall 23 is less.

Such a configuration allows, in addition, a distribution, in the transverse direction parallel to the axis T, of the compressive stress exerted vertically by the head 40 of the pin 4 on the heating element 5 once it has been put in place. in the housing 7 · This allows, on the one hand, to avoid any risk of partial displacement of the heating element in the housing 7, which could lead to generating noise. It is understood that, depending on the mounting clearance provided and respective manufacturing tolerances of the heating element 5 and the frame 3, it is possible, depending on the location, in the transverse direction axis T, of the receiving orifice 231 and as a function of the space, always in this transverse direction, of the head 40 of the pin 4 on the longitudinal wall 23, a residual clearance, potential source of relative movement of the heating element 5 within the frame 3, remains, for example at the edges 23a, 23b, previously defined, between the frame 3 and the heating element 5, once the latter installed in its housing 7

As previously stated, such a configuration allows a distribution of the compression stress exerted transversely by the pin 4 on said heating element 5. This makes it possible to limit the risks, over time, of localized damage, of the heating element 5. under the effect of this permanent mechanical stress, thus increasing the life of the heating device

According to the invention, the arrangement and the number of pins 4 within the same housing 7 are also of particular importance. Thus, according to a particularly advantageous embodiment, but not exclusive, the invention can provide that several receiving orifices 231 and corresponding pins 4 can be configured within the frame 3 · It goes without saying, in this case, that the orifices 231 receiving and associated pions 4 may all be identical or may have different features described above, taken separately or in combination, without damaging the invention: for example, it is quite possible, in this case, that some of the pins 4 arranged in the same housing 7 extend over the entire dimension, in the transverse direction T, of the longitudinal wall 23, while others occupy only partially this dimension. Similarly, in the longitudinal direction L, the pins 4 and associated receiving orifices 231 may, for all or part, be successively aligned or successively arranged in staggered relation to the median plane of the frame 3 previously defined. Finally, according to the vertical direction T, the heads 40 of the different pins 4 may or may not have the same dimension, or thickness: it is, by way of non-limiting example, quite conceivable, without affecting the invention , that the thickness of the heads 40 of the various pins 4 configured inside the same housing 7 increases, in the longitudinal direction, from the opening 50, previously defined, of the insertion path 26, by which the heating element 5 is introduced into said housing 7 towards the abutments 210 of the bottom wall 21 against which said heating element 5 is placed when it is inserted into its housing 7.

Whatever their number and their relative arrangement in the longitudinal direction L, the invention provides that at least one of the pins 4 and receiving ports 231 associated is arranged at vicinity of the bottom wall 21 previously defined.

The foregoing description clearly explains how the invention makes it possible to achieve the objectives which it has set itself and in particular to propose a heating device 1 in which the heating elements 5 are easily inserted and do not debate inside the device. However, the invention as described above can not be limited to the means and configurations exclusively described and illustrated, and it also applies to any equivalent means or configurations, as well as to any combination of such means or configurations. In particular, if the invention has been described and illustrated here in a case where receiving orifices 231 and pins 4 associated are configured on the first longitudinal wall 23 of a housing 7, it goes without saying that the invention applies also in the case where these receiving ports and associated pins are configured on the second longitudinal wall 25 of such a housing 7, and it also applies to the case in which receiving ports and associated pins are configured on each of these walls.

Claims

1. Frame (3) of an electric heater (1) of a flow of air flowing inside a ventilation, heating and / or air-conditioning system of a motor vehicle, said frame (3) comprising at least one heating compartment (30) having at least one housing (7) for receiving a heating element (5), the housing (7) being defined at least by two longitudinal walls (23, 25) defining vertically an insertion path (26) for the heating element (5), each longitudinal wall (23, 25) comprising an inner face (230a, 250a) oriented towards the insertion path, characterized in that the frame ( 3) comprises at least one holding member in position of the heating element (5) in the housing (7).

2. Frame (3) according to claim 1, characterized in that the holding member comprises at least one pin (4) configured to be inserted into a receiving orifice (231) arranged in one of the longitudinal walls (23). , 25).

3. Frame (3) according to the preceding claim, characterized in that the pin (4) comprises a head (40) intended to extend vertically projecting inside the housing (7) in which the heating element ( 5) is received and a foot (41) intended to be inserted into the receiving orifice (231) arranged in the longitudinal wall (23, 25).

4. Frame (3) according to the preceding claim, characterized in that the dimension, in particular longitudinal, of a lower face (400) of the head (40) of the pin (4) is greater than the dimension, in particular longitudinal, of the receiving orifice (231) -

5. Frame (3) according to one of claims 3 or 4, characterized in that the pin (4) comprises a base (42) extending vertically opposite the head (40) relative at the foot (41), the base (42) being configured so that the longitudinal wall (23, 25) in which is arranged the receiving orifice (231) is sandwiched between the lower face (400) of the head (40) and an upper face (420) of said base (42).

6. Frame (3) according to one of claims 3 to 5, characterized in that the foot (41) of the pin (4) has an opening (43) configured to allow deformation, in particular longitudinal, of said foot (41) when inserted into the receiving orifice (231) -

7. Frame (3) according to any one of claims 2 to 6, characterized in that the pin (4) extends over the entire transverse dimension of the longitudinal wall (23, 25) in which is arranged l receiving orifice (231) -

8. Frame (3) according to any one of claims 2 to 7, characterized in that the holding member comprises at least two receiving orifices (231) and associated pins (4) distributed over the longitudinal dimension of the wall longitudinal (23, 25).

9- Frame (3) according to any one of claims 2 to 8, characterized in that the receiving orifice (231) is arranged in the vicinity of a bottom wall (21) of the housing (7).

Electrical heating device (1) for a flow of air circulating inside a ventilation, heating and / or air-conditioning system of a motor vehicle, characterized in that it comprises at least a heating element (5) received in a housing (7) of a frame (3) according to any one of the preceding claims.