A method for manufacturing a vehicle part comprising a transparent or translucent portion

Abstract

The process (100) for manufacturing a vehicle part comprises the following steps: - masking (102) a portion of a transparent or translucent vehicle part body to form a masked portion of the part body; - applying (103) a layer of paint to the part body in an area encompassing all or part of the masked portion to form a painted area; - removing (104) the masking, the masked portion becoming an unmasked and unpainted portion; - irradiating (105) the paint layer with laser radiation in an area bordering the unmasked portion to define a clear paint boundary around the unmasked portion. Figure 1

Description

Title of the invention: Method for manufacturing a vehicle part comprising a transparent or translucent portion. Technical field

[0001] The present invention relates to a method for manufacturing a vehicle part, particularly intended for use in applications requiring transparent or translucent areas. The invention also relates to a vehicle part, a lighting component for a motor vehicle, and a motor vehicle. Prior art

[0002] A vehicle includes several transparent parts designed to transmit light. These include parts used for signaling or regulatory lighting purposes, for example, those protecting the optical units of the high and low beam headlights or the turn signals. Furthermore, the vehicle may also have light sources designed for decorative purposes that enhance the vehicle's appearance.

[0003] One of the wishes of automotive manufacturers' design teams is to be able to integrate lighting or signaling areas into a painted body panel without any gaps or the appearance of an added part. However, it is necessary that these areas comply with regulatory photometric standards, particularly regarding transmitted light intensity. To achieve this, it is particularly important, for certain lighting or signaling functions, to prevent a transparent or translucent material used in the part in question from transmitting light that is too diffuse with respect to the required regulatory intensities, unless excessively high luminous power is required to compensate for the diffusion.

[0004] The problem is therefore to be able to paint a vehicle part while maintaining on the same part an area of ​​transparency or translucency, allowing the transmission of light emitted by a light source, respecting the regulatory standards of photometry.

[0005] In the prior art, particularly in the process described in document FR3095620, a masking method is known, consisting of applying a temporary adhesive to a portion of the part to mask that portion. The next step consists of applying a layer of paint to the part, then removing the masking. The unmasked portion forms the transparent or translucent part of the component, allowing light transmission.

[0006] This process does not alter the optical properties of the unmasked portion, and, in particular, does not increase the diffuse nature of the transmitted light, so that it is It is possible to transmit light that complies with regulatory standards provided that the material chosen is suitable.

[0007] However, after the masking is removed, the edge of the unmasked area, forming the boundary between the painted and unmasked areas, is often indistinct, unsightly, and may exhibit loss of adhesion, which is unacceptable. For this reason, the masking process is generally used when the unpainted area being masked has a style line, such as a gouge or edge line, which also provides a visual separation from the painted part of the workpiece. This style line is helpful in implementing the process, particularly for applying the adhesive at the beginning of the process and then for concealing imperfections in the finished product within or behind the raised areas of the style line.

[0008] An alternative laser irradiation process is known, notably from the same document FR3095620. After applying the paint layer, the portion of the part to be made transparent or translucent is irradiated with a laser, so as to remove the paint from that portion. This process makes it possible to define a clear, aesthetically pleasing, and adherent boundary between a painted area of ​​the part and an unpainted area.

[0009] However, laser irradiation can alter the surface of the part, making the light passing through it particularly diffuse. This process therefore makes it difficult to comply with regulatory photometric standards for equivalent light sources. The irradiation process is also longer than the masking process, especially when a regulatory standard requires a large illuminated area.

[0010] It should be noted that these two processes are known to those skilled in the art as purely alternative solutions to each other, as is the case in document FR3095620. Indeed, they implement two completely different technologies for the same purpose, generate defects which at first glance are likely to be cumulative, which does not encourage those skilled in the art to imagine a complementary use.

[0011] The invention aims in particular to make a lighting zone appear on a vehicle part, without play, without the effect of an added part, and avoiding as much as possible the disadvantages of the two methods mentioned above. Summary of the invention

[0012] The present invention aims to overcome these limitations by proposing a method for manufacturing a vehicle part, comprising the following steps:

[0013] - masking a portion of a transparent vehicle part body or translucent, so as to form a masked portion of the body of the piece;

[0014] - application of a layer of paint to the body of the part, in an area encompassing all or part of the masked portion, so as to form a painted area;

[0015] - removal of the masking, the masked portion becoming an unmasked portion and devoid of paint;

[0016] - irradiation, with laser radiation, of the paint layer, in a border of the unmasked portion, so as to define a clear paint boundary around the unmasked portion.

[0017] Thus, the invention takes advantage of the benefits of both prior art methods and minimizes their respective drawbacks. In particular, laser irradiation is applied only to the edge of the unmasked portion and not to the entire portion of the part intended to be transparent or translucent. The method is therefore both fast, by targeting only the edge with laser irradiation (which is slower than the masking method), and achieves a satisfactory result both in terms of light transmission through the masked area and in terms of the aesthetic quality of the edge of this area, thanks to the laser irradiation process.

[0018] Other optional features taken alone or in combination follow.

[0019] Preferably, the process includes a step of manufacturing the body of the transparent or translucent part by molding a plastic, for example polycarbonate, polyamide, polyethylene terephthalate, butylene polyethylene terephthalate, polyurethane, polyvinyl chloride, acrylonitrile butadiene styrene, styrene acrylonitrile, acrylonitrile styrene acrylate, polymethyl methacrylate, cyclo-olefin copolymer or cyclo-olefins-polymer.

[0020] Advantageously, the plastic is a transparent or translucent polypropylene.

[0021] Indeed, this material is particularly suitable for manufacturing body parts subjected to deformation stresses and minor impacts, especially large parts. Furthermore, it can also be made translucent or transparent, and thus used to create luminous components for vehicles. However, its surface is altered during laser irradiation, modifying the transparency and diffusion of light passing through the material. Therefore, the process according to the invention makes it possible to benefit from the advantages associated with using transparent or translucent polypropylene to produce at least a portion of a transparent or translucent vehicle part, while avoiding, by confining the laser irradiation to a border, a greater part of the drawbacks associated with implementing an irradiation step using laser radiation.

[0022] Preferably, the irradiation step further includes irradiation, from the clear paint boundary, of a portion of the painted area, so as to form an intermediate zone located between the unmasked portion and the rest of the painted area.

[0023] Thus, the process allows the formation, between a transparent or translucent area, without alteration of the surface, and a painted area, of an intermediate zone, with or without alteration of the surface depending on the material forming the part. This intermediate zone allows light to pass through but may have photometric characteristics different from those of the transparent or translucent zone, so as to generate aesthetic effects and / or a transition effect between the transparent or translucent zone and the painted zone.

[0024] Advantageously, the irradiation step is implemented so as to form one or more specific patterns in the intermediate zone, for example hatching

[0025] Thus, the intermediate zone has one or more patterns that make it aesthetically pleasing. The irradiation stage offers various aesthetic choices.

[0026] Advantageously:

[0027] - the masking step includes the installation of a covering means temporary,

[0028] - the step of applying the paint layer includes the application of a primer opaque adhesion, preferably dark, and the application of a base coat in a predetermined shade.

[0029] Preferably, the process further includes the application of a layer of varnish to the part.

[0030] Advantageously, the application of a layer of varnish takes place after the laser irradiation step.

[0031] The invention also relates to a vehicle part obtained by the manufacturing process as stated above, comprising:

[0032] - a transparent or translucent portion formed by the unmasked portion;

[0033] - a painted portion formed by the painted area.

[0034] Advantageously, the part also includes an intermediate portion formed by the intermediate zone, between the transparent or translucent portion and the painted portion.

[0035] Preferably, the transparent or translucent portion has a haze coefficient value that is at least 10% lower than the haze coefficient value of the intermediate zone, preferably at least 20%, and preferably at least 30%.

[0036] This haze coefficient corresponds to the "coefficient of haze" known to those skilled in the art. It can also be defined as the ratio between diffuse light transmission and total light transmission.

[0037] Thus, the intermediate portion is a transition zone that can be lit but is primarily for aesthetic purposes.

[0038] The invention also relates to a luminous component for a motor vehicle, comprising a part as stated above and a light source intended to illuminate at least a part of the transparent or translucent portion of the part.

[0039] Preferably, this luminous component forms one of the following elements:

[0040] - a daylight;

[0041] - a position light;

[0042] - a turn signal;

[0043] - a reversing light;

[0044] - a lighthouse

[0045] The invention also relates to a motor vehicle comprising at least one part as described above and / or at least one lighting component as described above.

[0046] An exterior vehicle component is also described having a main surface, comprising the part as stated above, corresponding to at least twice the surface area of ​​the part, the exterior component forming for example a bumper, a grille, a wing, a rear roof deflector, a hood or a tailgate panel.

[0047] Advantageously, the vehicle part comprises several materials. Brief description of the figures

[0048] The invention will be better understood upon reading the following description, given solely by way of example and made with reference to the accompanying drawings in which: - The [Fig. 1] is a flowchart of a manufacturing process for a vehicle part according to a first implementation method of the invention; - Fig. 2 is a cross-sectional view of a vehicle part in the context of a manufacturing process of Fig. 1, according to the first method of implementation; - Fig. 3 is a cross-sectional view of a vehicle part as part of the manufacturing process; - Fig. 4 is a cross-sectional view of a vehicle part as part of the manufacturing process; - Fig. 5 is a cross-sectional view of a vehicle part as part of the manufacturing process; - Fig. 6 is a cross-sectional view of a vehicle part as part of the manufacturing process; - Fig. 7 is a cross-sectional view of a vehicle part within the framework of the manufacturing process; - Fig. 8 is a front view of the part obtained; - Fig. 9 is a view of a vehicle including the part obtained; - Figure 10 is a flowchart of a manufacturing process for a part of vehicle according to a second embodiment of the invention; - The [Fig. 11] is a cross-sectional view of a vehicle part in the context of a manufacturing process of the [Fig. 10], according to the second method of implementation; - Fig. 12 is a front view of the part obtained by the second method of implementation; - Fig. 13 is a view of a vehicle including the part obtained by the second method of implementation; - Fig. 14 is a cross-sectional view of a vehicle part obtained by a variant of the process in Fig. 10. Detailed description

[0049] With reference to Figures 1 to 8, a method 100 for manufacturing a vehicle part 11 is described below. In particular, according to the present embodiment, the vehicle part 11 is a vehicle body part. According to other embodiments, the vehicle part may be a part other than a body part. This method is implemented by means known to those skilled in the art and which are not the subject of the invention.

[0050] In step 101, a vehicle body part 1 is obtained by molding, preferably by injection, of transparent or translucent polycarbonate.

[0051] A material is defined as "transparent" if it has a transparency rate of 80% or higher and a haze coefficient of 30% or lower. A material is defined as "translucent" if it has a transparency rate between 20% and 80% and a haze coefficient between 30% and 90%. A "transparent or translucent" material, therefore, has, in the sense of the invention, a transparency rate of at least 20% and a haze coefficient of 90% or lower. The "haze coefficient" refers to the coefficient of haze, which is known to those skilled in the art. It can also be defined as the ratio between diffuse light transmission and total light transmission.

[0052] In step 102, a portion 2 of the body of part 1 is masked so as to cover this masked portion 2 of the part. This masking includes the placement of a temporary covering means 3 on the portion 2, as illustrated in [Fig. 3].

[0053] In step 103, a coat 4 of paint is applied to the body of the part 1, in an area encompassing the entire masked portion 2, so as to form a painted area as illustrated in [Fig. 4]. According to the present embodiment, the application of the paint coat 4 comprises the application of a dark, opaque adhesion primer 6, and the application of a base coat 7 in a predetermined shade. These elements are illustrated in [Fig. 5].

[0054] In an unillustrated variant, other choices of primary 6 and base layer 7 are made.

[0055] In an unillustrated variant, only one coat is applied: the paint is a single-coat paint. This is, for example, a single coat that is opaque to light. It could, in particular, be a lacquer. It could also be a single-coat paint whose aesthetic equivalent is a combination of a base coat and a varnish. It is also possible to combine such a single-coat paint with a primer.

[0056] Conversely, in another variant not illustrated, several layers follow one another.

[0057] In an unillustrated variant, the painted area encompasses only part of the masked portion 2. This saves paint, for example in the center of the masked portion.

[0058] In step 104, the masking is removed, the masked portion 2 becoming an unmasked portion 2 and devoid of paint, as illustrated in [Fig.5].

[0059] In step 105, irradiation is carried out, with laser radiation, of the layer 4 of paint, in a border 8 of the unmasked portion 2, so as to define a clear limit of paint around the unmasked portion 2, as illustrated in [Fig.6].

[0060] For the sake of simplicity, with the exception of [Fig.5], the paint layer 4 is represented as a single layer without distinction between the adhesion primer layer 6 and the base layer 7. Of course, as indicated previously, depending on the embodiments, the composition of the paint layer 4 can vary and in particular be a single layer.

[0061] In step 106, a step is carried out involving the application of a layer of varnish (not shown) on the part.

[0062] This process yields 100 a vehicle part 1 comprising:

[0063] - a transparent or translucent portion formed by the unmasked portion 2;

[0064] - a painted portion formed by the painted area 5.

[0065] These transparent or translucent and painted portions are separated by a clear paint boundary.

[0066] The part 11 obtained is also illustrated, front view, in [Fig.8].

[0067] In an unillustrated variant, the irradiation step extends into the painted area 5. Since laser irradiation does not significantly alter the surface of polycarbonate, the transparency and diffusion of light passing through an area The irradiated area is no different from that passing through the transparent or translucent portion 2. Thus, extending the irradiation into the painted area is equivalent, in this embodiment, to replacing a part of the painted portion 5 with an extension of the transparent or translucent portion 2.

[0068] Figure 9 illustrates a vehicle 12 comprising two lighting components 10 for a motor vehicle. These lighting components 10 include the vehicle part 11. A light source, not shown, is located inside the vehicle, opposite each part 11, so as to emit light which will pass through the transparent or translucent portion 2.

[0069] These luminous components 10 form, according to the intended functionalities, one of the following elements:

[0070] - a daylight;

[0071] - a position light;

[0072] - a turn signal;

[0073] - a reversing light; or

[0074] - a lighthouse.

[0075] A second method of implementing the manufacturing process, referenced 200 and illustrated in [Fig. 10], is described below.

[0076] In step 201, a vehicle body part 1 is obtained, this time by molding, preferably by injection, of transparent or translucent polypropylene.

[0077] Steps 202 to 206 are similar to steps 102 to 106.

[0078] The part obtained is illustrated in figures 11 and 12. The numerical references corresponding to elements similar to those of the previous mode are provided with an apostrophe to differentiate this part from that obtained by process 100.

[0079] The irradiation step 207, added compared to process 100, further includes irradiation, from the clear paint limit of the border 8', of a portion of the painted area 5', so as to form an intermediate area 9 located between the unmasked portion 2' and the rest of the painted area 5'.

[0080] This process therefore yields a vehicle part 200 comprising:

[0081] - a transparent or translucent portion formed by the unmasked portion 2';

[0082] - a painted portion formed by the painted area 5';

[0083] - an intermediate portion formed by the intermediate zone 9, between the portion transparent or translucent 2' and the painted portion 5'.

[0084] The light passing through the irradiated intermediate portion 9 is more diffuse and of lower luminous intensity compared to that passing through the transparent portion 2 of the part 11 obtained by process 100, due to the laser irradiation of the intermediate zone 9. In particular, the irradiation of the painted zone of the polypropylene generates the presence of a thin residue layer, and / or an alteration of the optical properties of the polypropylene surface.

[0085] This difference in transparency and diffusion generates an aesthetic and transitional effect between portion 2' and portion 5'. It is advantageous, from an aesthetic point of view, that the transparent or translucent portion 2' has a haze coefficient value that is at least 10% lower than the haze coefficient value of the intermediate portion, preferably at least 20%, and preferably at least 30%.

[0086] Figure 13 illustrates a vehicle 12' comprising two lighting components 10' for a motor vehicle. These lighting components 10' comprise the vehicle part 11'. One or more light sources, not shown, are located inside the vehicle, opposite each part 11, so as to emit light that will pass through the transparent or translucent portion 2. The lighting components 10' form the same elements as the lighting components 10.

[0087] In a variant of the process 200, the irradiation step 207 is implemented so as to form one or more specific patterns in the intermediate zone 9', for example, hatching, by alternately irradiating this intermediate zone 9'. The result is that shown schematically in [Fig. 14], which includes additional apostrophes for each numerical reference corresponding to a similar element of the preceding embodiment. The resulting aesthetic effect is therefore different again.

[0088] In an unillustrated sub-variant, the irradiation step 207 is implemented so as to generate patterns that evolve progressively in the intermediate zone 9', between zone 2” and the painted zone 5”. For example, the irradiated hatchings become more and more spaced out or less and less wide, starting from the unmasked portion 2”, as one approaches the painted zone 5”. The aesthetic effect generated is therefore yet another different.

[0089] In an unillustrated embodiment, the polypropylene obtained in step 201 differs from that obtained in the mode described above in that its transparency and the diffusive nature of the light passing through it will be different. Those skilled in the art know how to vary the manufacturing characteristics of the material in order to vary the parameters of the material's interaction with light. Consequently, these parameters will also be different with regard to the intermediate portion 9 or 9'.

[0090] As an alternative to the processes described, the body of part 1 is obtained by molding one of the following materials: polyamide, polyethylene terephthalate, butylene terephthalate, polyurethane, polyvinyl chloride, acrylonitrile butadiene styrene, styrene acrylonitrile, acrylonitrile styrene acrylate, polymethyl methacrylate, cyclo-olefin copolymer or cyclo-olefins-polymer.

[0091] Alternatively, part 11 or 11' can be integrated into any exterior vehicle component having a main surface, including part 11 or 11', in particular with a size at least twice the size of the surface of part 11 or 11', the exterior component forming, for example, a bumper, grille, fender, rear roof spoiler, hood, or tailgate panel. In these variations, a portion of the main surface of the component comprises a material different from the material of the part.

[0092] The invention is not limited to the embodiments shown and other embodiments will be obvious to a person skilled in the art. List of references

[0093] 1, 1', 1": vehicle part body 2, 2', 2": masked area - unmasked area - transparent or translucent portion

[0094] 3: means of temporary covering

[0095] 4, 4', 4": layer of paint

[0096] 5, 5', 5": painted area - painted portion

[0097] 6: adhesion primer

[0098] 7: base layer

[0099] 8, 8', 8": border

[0100] 9', 9": intermediate zone - intermediate portion

[0101] 10, 10': luminous component 11, 11': vehicle part

[0102] 12, 12': vehicle

Claims

Demands

1. Method (100; 200) of manufacturing a part (11; 11'; 11") of a vehicle, characterized in that it comprises the following steps: - masking (102; 202) of a portion (2; 2'; 2") of a part body (1; 1'; 1"), of a vehicle, transparent or translucent, so as to form a masked portion of the part body (1; 1'; 1"); - application (103; 203) of a layer of paint (4; 4'; 4") on the body of the part (1; 1'; 1"), in an area encompassing all or part of the masked portion, so as to form a painted area (5; 5'; 5"); - removal (104; 204) of the masking, the masked portion becoming an unmasked and unpainted portion (2; 2'; 2"); - irradiation (105; 205), with a laser beam, of the layer (4; 4'; 4") of paint, in a border (8; 8') of the unmasked portion (2; 2'; 2") so as to define a clear paint boundary around the unmasked portion.

2. A method (100; 200) according to claim 1, comprising a step (101; 201) of manufacturing the transparent or translucent part body (1; 1'; 1") by molding a plastic, for example polycarbonate, polyamide, polyethylene terephthalate, butylene polyethylene terephthalate, polyurethane, polyvinyl chloride, acrylonitrile butadiene styrene, styrene acrylonitrile, acrylonitrile styrene acrylate, polymethyl methacrylate, cyclo-olefin copolymer or cyclo-olefins-polymer.

3. Method (200) according to the preceding claim, wherein the plastic is a transparent or translucent polypropylene.

4. A method (200) according to any one of the preceding claims, wherein the irradiation step (205) further comprises irradiation, from the net paint boundary, of a portion of the painted area (5'; 5"), so as to form an intermediate zone (9; 9') situated between the unmasked portion (2'; 2") and the rest of the painted area (5'; 5").

5. A method (200) according to the preceding claim, wherein the irradiation step (205) is implemented so as to form one or more specific patterns in the intermediate zone (9'), for example hatching.

6. A method (100; 200) according to any one of the preceding claims, wherein: - the masking step (102; 202) includes the placement of a temporary covering means (3), - the application step (103; 203) of the paint layer (4; 4'; 4") includes the application of an opaque adhesion primer (6), preferably dark, and the application of a base coat (7) in a predetermined shade.

7. Vehicle part (11; 11') obtained by the manufacturing process (100; 200) according to any one of the preceding claims, comprising: - a transparent or translucent portion formed by the unmasked portion (2; 2'; 2"); - a painted portion formed by the painted area (5; 5; 5").

8. Part (11') according to the preceding claim in combination with claim 4, also comprising an intermediate portion formed by the intermediate zone (9; 9'), between the transparent or translucent portion (2; 2'; 2") and the painted portion (5; 5'; 5").

9. Vehicle part (11) according to any one of claims 7 or 8, wherein the transparent or translucent portion has a haze coefficient value that is at least 10% lower than the haze coefficient value of the intermediate zone, preferably at least 20%, and preferably at least 30%.

10. A light component (10; 10') for a motor vehicle, comprising a part (11; 11') according to any one of claims 7 to 9 and a light source intended to illuminate at least a part of the transparent or translucent portion (2; 2'; 2") of the part (11; 11').

11. Light component (10; 10') according to the preceding claim, forming one of the following elements: - a daytime running light; - a position light; - a turn signal; - a reversing light; - a headlight.

12. Motor vehicle (12; 12') comprising at least one part (11; 11') according to any one of claims 7 to 9 and / or at least one lighting component (10; 10') according to claim 10 or 11.

Images