FR3108463A1 - Electric heating device with printed circuit comprising a guide element - Google Patents

Abstract

Printed circuit (51) for an electric heating device (1) of a motor vehicle, said printed circuit (51) comprising holes (511) for inserting connection tabs (521) of electrical or electronic elements (520), the printed circuit (51) comprising at least one guide element (60) fixed to one face of the said printed circuit (51), the said guide element (60) comprising at least one through hole (61) intended to receive a connection tab (521) of an electrical or electronic element (520), said at least one orifice (61) being arranged opposite a corresponding insertion hole (511) of the printed circuit (51). Abstract Figure: Fig 2a

Description

Electric heating device with printed circuit comprising a guide element

The field of the present invention is that of electrical devices for heating and circulating a heat transfer liquid, in particular for a ventilation, heating and/or air conditioning installation for the passenger compartment of a motor vehicle. More particularly, the invention relates to electric heating devices used for such installations in motor vehicles, electric or hybrid, equipped with a high-voltage power supply network.

The heating of the air intended for the heat treatment of the passenger compartment of a motor vehicle with combustion engine is ensured by heat exchange between a flow of air and a heat transfer liquid, by means of a radiator. In the case of hybrid or electric vehicles, electric heating devices are known which form a heat source and in which a generally high-voltage electric current circulates to raise the temperature of an electric heating element on board this heating device. The heat transfer liquid to be heated thus passes through the electric heating device and is brought into contact with the electric heating element, an exchange of heat energy then takes place between the electric heating element and the heat transfer liquid. This heat transfer liquid then passes through the radiator located within the ventilation, heating and/or air conditioning system in order to heat the air flow to the passenger compartment.

The electrical heating element usually consists of electrical heating means, for example one or more heating resistors. In order to power and control such an electric heating element, the electric heating device generally comprises an electronic control printed circuit. This electronic printed circuit comprises electrical or electronic elements which are fixed and electrically connected by means of fixing lugs. However, during the assembly of these electrical or electronic elements, the fixing lugs can be twisted, offset, which makes it difficult to insert them into dedicated connection holes on the printed circuit. It is then necessary to manipulate these electrical or electronic elements in order to straighten and reposition their fixing lugs. This manipulation is time-consuming and therefore increases production costs. In addition, during this manipulation, the connection tabs can break, rendering the element unusable.

The object of the present invention is therefore to at least partially remedy the drawbacks of the prior art and to propose an electric heating device with an improved manufacturing process.

The present invention therefore relates to a printed circuit for an electric heating device of a motor vehicle, said printed circuit comprising holes for inserting connection tabs for electrical or electronic elements,
the printed circuit comprising at least one guide element fixed to one face of said printed circuit, said guide element comprising at least one through hole intended to receive a connection lug of an electrical or electronic element, said at least one hole being disposed opposite a corresponding insertion hole (511) of the printed circuit.

According to one aspect of the invention, the guide element is fixed by clipping onto the printed circuit.

According to another aspect of the invention, the guide element comprises fixing fingers which are inserted into specific orifices provided in the printed circuit, the end of these fingers being of a diameter greater than the diameter of the orifices and said fingers being forcibly inserted into said orifices.

According to another aspect of the invention, the printed circuit has a spacing of between 0.5 and 1.5 mm between the printed circuit and the guide element.

According to another aspect of the invention, the face of the guide element facing the printed circuit comprises at least one abutment surface, said at least one abutment surface being disposed at a height greater than the mouth of the orifices, said at least one abutment surface coming into contact with the printed circuit.

According to another aspect of the invention, the at least one orifice of the guide element comprises a flare, the widest part of which opens onto a face of the guide element arranged opposite the printed circuit.

According to another aspect of the invention, the edge of the flare opening onto a face of the guide element arranged opposite the printed circuit is rounded.

According to another aspect of the invention, the at least one orifice of the guide element comprises a cylindrical section opening onto a face of the guide element arranged opposite the printed circuit, said cylindrical section being arranged in the same axis as the insertion hole of the printed circuit corresponding to said orifice.

According to another aspect of the invention, the cylindrical section extends over at least 50% of the thickness of the guide element.

According to another aspect of the invention, the guide element comprises at least one series of orifices aligned with each other.

According to another aspect of the invention, the guide element comprises at least two series of orifices aligned with each other, said series being arranged parallel to each other.

• mise en place d’au moins un élément de guidage sur une face dudit circuit imprimé, ledit élément de guidage comportant au moins un orifice traversant, ledit au moins un orifice étant disposé en vis à vis d’un trou d’insertion du circuit imprimé,
• fixation dudit au moins un élément de guidage sur le circuit imprimé,
• mise en place d’éléments électriques ou électroniques sur le circuit imprimé par insertion d’au moins une patte de connexion d’au moins un éléments électriques ou électroniques successivement dans le ou les orifice de l’élément de guidage et le ou les trou d’insertion correspondant du circuit imprimé,
• soudure des patte de connexion sur le circuit imprimé.

The present invention also relates to a method of manufacturing a printed circuit for an electric heating device of a motor vehicle, said printed circuit comprising holes for inserting connection tabs of electrical or electronic elements, said manufacturing method comprising the following steps:

• positioning of at least one guide element on one side of said printed circuit, said guide element comprising at least one through hole, said at least one hole being arranged opposite an insertion hole of the printed circuit ,
• fixing said at least one guide element on the printed circuit,
• installation of electrical or electronic elements on the printed circuit by inserting at least one connection lug of at least one electrical or electronic element successively into the hole or holes of the guide element and the hole or holes corresponding insertion of the printed circuit,
• soldering the connection tabs on the printed circuit.

Other characteristics and advantages of the present invention will appear more clearly on reading the following description, provided by way of illustration and not limitation, and the appended drawings in which:

FIG. 1a is a schematic representation in perspective of an electric heating device,

FIG. 1b is a schematic representation in exploded perspective of the electric heating device of FIG. 1a,

FIG. 2a is a schematic representation in perspective of one side of a printed circuit of the electric heating device,

Figure 2b is a schematic representation in perspective of the opposite face of the printed circuit of Figure 2a,

FIG. 3a is a diagrammatic representation in section of a printed circuit and of a guide element at the level of its orifices,

FIG. 3b is a diagrammatic sectional representation of a printed circuit and of a guide element at the level of its fixing with said printed circuit,

Figure 4 is a schematic representation in perspective of a guide element according to a first embodiment,

FIG. 5 is a schematic representation in perspective of a guide element according to a second embodiment,

FIG. 6 is a flowchart of the different steps of a method of manufacturing an electric heating device.

In the various figures, identical elements bear the same reference numbers.

The following achievements are examples. Although the description refers to one or more embodiments, this does not necessarily mean that each reference is to the same embodiment, or that the features apply only to a single embodiment. Single features of different embodiments may also be combined and/or interchanged to provide other embodiments.

In the present description, it is possible to index certain elements or parameters, such as for example first element or second element as well as first parameter and second parameter or else first criterion and second criterion, etc. In this case, it is a simple indexing to differentiate and name elements or parameters or criteria that are close, but not identical. This indexing does not imply a priority of one element, parameter or criterion over another and it is easy to interchange such denominations without departing from the scope of the present description. Nor does this indexing imply an order in time, for example, to assess such and such a criterion.

Figures 1a and 1b show a schematic representation in perspective of an electric heating device 1 respectively in assembled view and in exploded view.

The electric heating device 1 comprises a casing delimiting at least one heating chamber 3 inside which the heat transfer liquid is intended to circulate. More specifically, the heating chamber 3 comprises a cavity 32 within which the heat transfer liquid enters and leaves the heating chamber 3 at the level of connection end pieces 3a opening out into said cavity 32. In FIGS. 1a and 1b, only a connection end piece 3a, for example, an outlet is shown. The heating chamber 3 also includes another inlet connection end piece (not shown).

Within this heating chamber 3 extends at least one electric heating element 31 intended to heat the heat transfer liquid. This electrical heating element 31 may for example comprise one or more electrical resistors and having a helical profile and intended to come into contact with the heat transfer liquid. The electric heating element 31 closes in particular the heating chamber 3 and more precisely the cavity 32 so that the heat transfer liquid can only circulate from one inlet connection end piece to an outlet connection end piece 3a.

The electric heating device 1 may also include an extension 4 of the heating chamber 3, allowing access to the electrical connectors of the electric heating element 31. This extension 4 can be closed by means of a cover 41. The liquid coolant does not circulate in this extension 4.

The electric heating device 1 also comprises a housing 5 within which is arranged a printed circuit 51 electronic management. This housing 5 may in particular comprise a cover 52 which closes it. The housing 5 also includes electrical connectors 50 allowing the electrical supply of the printed circuit 51, generally in low voltage current (for example from 12 to 48 V), and also of the electric heating element 31, generally in high voltage current ( for example that can go beyond 500 V for an electric vehicle).

FIGS. 2a and 2b show the printed circuit 51 in greater detail. The printed circuit 51 comprises in particular electrical or electronic elements 520. These electrical or electronic elements 520 can be electronic components such as electronic chips, transistors or resistors or even elements such as electrical connectors or transformers. These electrical or electronic elements 520 include in particular connection tabs 521 allowing the electrical connection and their fixing with the printed circuit 51. For this, the printed circuit 51 comprises insertion holes 511 in which the connection tabs 521 of the elements pass. electrical or electronic 520.

Printed circuit 51 also comprises at least one guide element 60 fixed to one face of said printed circuit 51. Guide element 60 comprises at least one through hole 61 intended to receive a connection lug 521 of at least one electrical element or electronic 520. By traversing, it is meant here that the orifice 61 passes right through the guide element 60 and is open on both sides. Said at least one orifice orifice 61 is arranged opposite a corresponding insertion hole 511 of the printed circuit 51 (visible in more detail in FIG. 3a). More precisely, the orifice 61 is aligned with the corresponding insertion hole 511 so that their axes coincide. By corresponding, it is meant here that an orifice 61 can only be arranged opposite a single corresponding insertion hole and vice versa.

This orifice 61 allows during the assembly of the printed circuit 51 and in particular during the establishment of the at least one electrical or electronic element 520 to guide the connection tab 521 towards the corresponding insertion hole 511 which is intended for it. Thus, the risks of incorrect installation of the connection bracket 521 are reduced. In addition, the orifices 61 allow this connection lug 521 to be straightened in the event that the latter is twisted. Moreover, when the guide element comprises at least two orifices 60 and the electric or electronic element 520 comprises at least two connection lugs 521, the guide element 60 and its orifices 61 also makes it possible to straighten the lugs of connection 521 in order to put them back substantially parallel to each other before inserting them into the insertion holes 511.

In the examples illustrated in FIGS. 2a to 5, the guide elements 60 comprise several orifices 61. In the rest of the description, we will thus speak of the orifices 61 in the plural in order to characterize them. The characteristics described of the said orifices 61 are nevertheless independent of the number of orifices 61 present on the guide element 60.

In the example illustrated in FIGS. 2a and 2b, the printed circuit 51 comprises more particularly three guide elements 60. The guide elements 60 can in particular be made of an electrically non-conductive material, such as for example a plastic material such as polyterephthalate. of butylene (PBT) filled or not with fiberglass.

As shown in more detail in Figure 3a, the orifices 61 of the guide element 60 may in particular comprise a flare, the widest part of which opens onto a face of the guide element 60 disposed opposite the printed circuit. 51. The flare extends in particular through 360° in order to be present over the entire periphery of the mouth of the orifice 61. This flare notably allows good guidance and straightening of the connection tabs 521.

In order to further facilitate the insertion of the connection lugs 521 into the orifices 61 and in particular into the flares, the rim of the flare opening onto a face of the guide element 60 arranged opposite the printed circuit 51 is round.

The orifices 61 of the guide element 60 can also comprise, in the continuity of the widenings, a cylindrical section 612 emerging on one face of the guide element 60 arranged opposite the printed circuit 51. These cylindrical sections 612 are arranged on the same axis as the insertion holes 511 of the printed circuit 51 and allow good centering of the connection tabs 521. In order to effectively guide the connection tabs 521, the cylindrical section 612 can in particular extend over at least 50% of the thickness of the guide element 60.

The guide element 60 can thus for example have a total thickness of the order of 2.5 mm. The flares can extend over a height of the order of 1.2 mm with a slope of the order of 60° angle. The cylindrical section 612 then extends over a height of 1.3 mm.

The guide element 60 can in particular be fixed by clipping onto the printed circuit 51. The guide element 60 can thus comprise fixing fingers 63 which are inserted into specific orifices 512 provided in the printed circuit 51. end of these fingers 63 has a diameter greater than the diameter of the orifices 512 and the fingers 63 are inserted by force into the said orifices 512 in order to allow the clipping of the guide elements 60. When the guide element 60 is fixed to the circuit printed 51, at least one surface of the guide element 60 is adjacent to the printed circuit. Other known fastening means such as gluing, riveting, riveting or even screwing are also entirely possible.

In order to allow their fixing and in order to allow their electrical connection with the printed circuit 51, the electrical or electronic elements 520 are soldered to the printed circuit by means of a soldering material, generally tin. This solder material is applied at the level of the insertion holes 511 from the face opposite the electrical or electronic element 520 in order to solder the connection tab 521 to the printed circuit 51. Still as shown in FIGS. 3a and 3b, the electric heating device 1 may include a spacing E of between 0.5 and 1.5 mm between the printed circuit 51 and the guide element 60. This spacing E allows in particular the solder material, applied from the opposite face of s extend in order to ensure a good fixation and a good electrical connection of the electrical or electronic element 520.

The face of the guide element 60 opposite the printed circuit 51 may in particular comprise one or more abutment surfaces 613. These abutment surfaces 613 are arranged at a height greater than the mouth of the orifices 61. Thus, these abutment surfaces 613 come into contact with the printed circuit 51 so as to form the spacing E. These abutment surfaces 613 can in particular be arranged at the level of the fixing points of the guide element 60 such as for example at the level of the fingers 63 of fixation.

As shown in Figure 4, the guide element 60 may include at least one series of holes 61 aligned with each other. In a first embodiment illustrated in this figure 4, the orifices 61 are arranged in pairs of orifices 61 joined to each other. The guiding element 60 illustrated in FIG. 4 here comprises three pairs of orifices 61. This guiding element 60 can thus for example allow the guiding of three electrical or electronic elements 520 comprising two connection lugs 521 or else allow the guiding of a single electrical or electronic element 520 comprising six connection lugs 521 arranged identically to the orifices 61.

The guide element 60 can also comprise at least two series of orifices 61 aligned with each other, as illustrated in FIG. 5. These series being arranged parallel to each other. According to the embodiment illustrated in Figure 5, the orifices 61 can go in groups of three orifices joined to each other within the same series. The guide element 60 illustrated in FIG. 5 comprises two series each comprising two groups of three orifices 60. This guide element 60 can thus allow guidance for more complex electrical or electronic elements 520 comprising three connection lugs 521 or again for an electrical or electronic element 520 comprising twelve connection lugs 521 arranged identically to the orifices 61.

Other embodiments of the guide elements 60 can very well be envisaged in order to adapt to the configuration and to the number of connection tabs 521 of the electrical or electronic elements 520 as well as to the number of electrical or electronic element 520 .

The present invention also relates to a method of manufacturing a printed circuit 51 for an electric heating device 1 of a motor vehicle. This printed circuit 51 has insertion holes 511 in order to receive connection tabs 521 of electrical or electronic elements 520.

The flowchart in Figure 6 shows the different stages of the manufacturing process. The manufacturing process thus comprises the following steps:

A first step 101 of positioning at least one guide element 60 on one face of the printed circuit 51. This guide element 60 comprises at least one through hole 61. Said at least one orifice 61 is arranged opposite an insertion hole 511 of the printed circuit 51.

A second step 102 of fixing the guide element 60 on the printed circuit 51. As described above, this fixing can be carried out by clipping but other known fixing means such as gluing, riveting, riveting or even screwing are quite possible.

A third step 103 of positioning electrical or electronic elements 520 on the printed circuit 51 by inserting at least connection lugs 521 of at least one electrical or electronic element 520 successively into the orifice(s) 61 of the guide element 60 and in the corresponding insertion hole or holes 511 of the printed circuit 51. During this third step 103, the connection tabs 521 which are for example deformed or twisted are straightened by the guide element 60. This makes it easier to assemble the electrical or electronic elements 520 on the printed circuit 51. When the guide element comprises at least two orifices 60 and the electrical or electronic element 520 comprises at least two connection lugs 521, the guide element 60 and its orifices 61 also makes it possible to straighten the connection tabs 521 in order to return them substantially parallel to each other before their insertion into the insertion holes 511.

A fourth step 104 of soldering the connection tabs 521 on the printed circuit 51. This fourth step allows the fixing of the electrical or electronic elements 520 as well as their electrical connection with the printed circuit 51.

Thus, it is clear that the printed circuit 51 due to the presence of one or more guide elements 60 allows faster and easier assembly of said printed circuit 51. In addition, this makes it possible to limit the manipulation of the electrical or electronic elements 520 , thus limiting the risk of damaging them. The assembly time and therefore the production costs are thus reduced.

Claims (10)

Printed circuit (51) for an electric heating device (1) of a motor vehicle, said printed circuit (51) comprising holes (511) for inserting connection tabs (521) of electrical or electronic elements (520),
characterized in that the printed circuit (51) comprises at least one guide element (60) fixed to one face of the said printed circuit (51), the said guide element (60) comprising at least one through orifice (61) intended to receive a connection tab (521) of an electrical or electronic element (520), said at least one orifice (61) being arranged opposite a corresponding insertion hole (511) of the printed circuit (51). Printed circuit (51) according to the preceding claim, characterized in that the guide element (60) is fixed by clipping onto the printed circuit (51). Printed circuit (51) according to any one of the preceding claims, characterized in that it includes a spacing (E) of between 0.5 and 1.5 mm between the printed circuit (51) and the guide element ( 60). Printed circuit (51) according to any one of the preceding claims, characterized in that the at least one orifice (61) of the guide element (60) comprises a flare, the widest part of which opens onto a face of the guide element (60) arranged opposite the printed circuit (51). Printed circuit (51) according to the preceding claim, characterized in that the edge of the flare opening onto a face of the guide element (60) arranged opposite the printed circuit (51) is rounded. Printed circuit (51) according to any one of Claims 4 or 5, characterized in that the at least one orifice (61) of the guide element (60) comprises a cylindrical section (612) emerging on a face of the guide element (60) arranged opposite the printed circuit (51), said cylindrical section (612) being arranged in the same axis as the insertion hole (511) of the corresponding printed circuit (51) said orifice (61). Printed circuit (51) according to the preceding claim, characterized in that the cylindrical section (612) extends over at least 50% of the thickness of the guide element (60). Printed circuit (51) according to any one of the preceding claims, characterized in that the guide element (60) comprises at least a series of orifices (61) aligned with each other. Printed circuit (51) according to any one of the preceding claims, characterized in that the guide element (60) comprises at least two series of orifices (61) aligned with each other, the said series being arranged parallel to each other . Method of manufacturing a printed circuit (51) for an electric heating device (1) of a motor vehicle, said printed circuit (51) comprising holes (511) for inserting connection tabs (521) of electrical or electronic (520), said manufacturing method comprising the following steps:

• placing at least one guide element (60) on one face of said printed circuit (51), said guide element (60) comprising at least one through hole (61), said at least one hole (61) being arranged opposite an insertion hole (511) of the printed circuit (51),
• fixing said at least one guide element (60) on the printed circuit (51),
• placing electrical or electronic elements (520) on the printed circuit (51) by inserting at least one connection lug (521) of at least one electrical or electronic element (520) successively into the orifice(s) (61) of the guide element (60) and the corresponding insertion hole(s) (511) of the printed circuit (51),
• soldering of the connection tabs (521) on the printed circuit (51).