阅读说明：本技术 包括背光区域的车身部件 (Body part comprising a backlit area ) 是由 蒂埃里·雅克梅 大卫·特雷斯 杰罗姆·布里冉 斯蒂芬·格列尔 于 2019-12-30 设计创作，主要内容包括：本发明涉及一种制造上漆的塑料车身部件的方法,其中所述车身部件包括至少部分地由第一材料构成的第一区域,并包括至少一个由第二材料构成的透明或半透明的第二区域,所述方法包括在模具中注入所述第一材料以形成所述第一区域和注入所述第二材料以形成所述第二区域的模制步骤,与至少在所述第一区域上漆的上漆步骤。(The invention relates to a method for producing a painted plastic body part, wherein the body part comprises a first region which is at least partially made of a first material and comprises at least one transparent or translucent second region which is made of a second material, the method comprising a moulding step in which the first material is injected in a mould to form the first region and the second material is injected to form the second region, and a painting step in which at least the first region is painted.)

1. A method of manufacturing a painted plastic body part (1), wherein the body part comprises a first area (10) at least partly consisting of a first material, and at least one transparent or translucent second area (11) consisting of a second material, the method comprising a moulding step of injecting the first material in a mould to form the first area (10) and injecting the second material to form the second area (11), and a painting step of painting at least the first area (10).

2. The method of claim 1, comprising the steps of:

-applying a mask to a predetermined area (12) on the whole or part of the body part (1);

-painting the body part (1) as a whole;

-removing the mask.

3. The method of claim 1, comprising the steps of:

-painting the body part (1) as a whole;

-removing paint in a predetermined area (12) located on the whole or part of the body part (1) by means of a laser beam.

4. The method according to any one of the preceding claims, wherein the predetermined area (12) is located at least partially, preferably entirely, in the molded transparent portion (12) of the body component (12).

5. A method according to any one of the preceding claims, wherein the mould is connected to a plurality of injection nozzles controlled to perform a series of programmed injections, the injection nozzles being spaced apart from each other by a distance of at least 10mm and connected to containers containing different materials.

6. A method according to claim 5, comprising the step of determining the injection sequence and the amount of material injected for each injection nozzle.

7. The method of any one of the preceding claims, wherein the first material is selected from the group consisting of: talc filled polypropylene (PP) EDDM, Polyamide (PA), Polycarbonate (PC), Acrylonitrile Butadiene Styrene (ABS), blends of Polycarbonate (PC) and Acrylonitrile Butadiene Styrene (ABS).

8. The method of any of the preceding claims, wherein the second material is selected from the group consisting of: translucent natural polypropylene, Cyclic Olefin Copolymer (COC), Polyethylene (PE), Polyamide (PA), Polycarbonate (PC), Acrylonitrile Butadiene Styrene (ABS), a mixture of Polycarbonate (PC), Acrylonitrile Butadiene Styrene (ABS), Polystyrene (PS) and Polymethylmethacrylate (PMMA).

9. A vehicle body component (1) obtained by the manufacturing method according to any one of claims 1 to 8.

10. A motor vehicle comprising at least one body part (1) according to claim 9.

Technical Field

The present invention relates to the field of motor vehicles, and more particularly to the field of motor vehicle bodywork parts comprising transparent or translucent elements.

Background

An element is said to be transparent when it passes light in the visible range. Elements with a transmission of about 90% are considered transparent. An element is translucent when it passes light in the visible range but does not allow objects to be clearly identified. An element having a transmittance of about 60% is considered to be translucent.

The transmittance of a material is the proportion of the light flux that passes through the material. Thus, transmittance represents the ratio of the intensity of light transmitted by a material to the intensity of incident light.

Elements attached to body parts are known, which aim in particular to highlight the style of the vehicle, for example lines or shapes which the manufacturer desires to associate with the image of his vehicle type. This is for example a chrome-plated tape or strip arranged at the edge of the component or device. In order to enhance the aesthetic effect produced by these body elements, it has been proposed to arrange the light source behind the transparent surface of the body element.

By way of example, chrome-plated belts extending along the sides of the vehicle, underbody protectors, logos of trademarks, door handle trims, rearview mirror housings are stylistic parts that vehicle manufacturers are particularly interested in designing. By way of further extension, all externally visible parts of the body which contribute to the overall appearance of the vehicle (e.g. openings, bumpers, radiator grilles) can also be considered body elements.

It is known to mould bodywork parts from plastic material, to which a transparent element is attached, which is located in a housing specially provided for this purpose.

The disadvantages of these transparent elements are: must be perfectly matched to the receptacle on the body part. Secondly, when such optical elements are assembled to a vehicle body part, gaps or surface differences may occur which have a visual quality which is lower than that required for the assembly of a motor vehicle. Finally, such attachment elements may lead to complexity in the management of the tightness.

Disclosure of Invention

The object of the present invention is in particular to remedy these drawbacks by proposing a simple, effective and inexpensive method of manufacturing painted plastic body parts comprising transparent or translucent areas. It is also an object of the present invention to provide a painted plastic body part including a solid and sealed transparent area.

To achieve this effect, the subject of the invention is a method for manufacturing a painted plastic body part, wherein the body part comprises a first region composed at least partially of a first material and comprises at least one transparent or translucent second region composed of a second material, the method comprising a molding step of injecting the first material in a mold to form the first region and injecting the second material to form the second region, and a painting step of painting at least the first region.

The method enables a body part to be obtained in one piece, consisting of two different materials and having a transparent or translucent area. The resulting body part is in particular solid and particularly strong and free from voids, gaps or surface differences resulting from the assembly of the two parts, which could affect the appearance and the tightness of the parts.

By "transparent material" is meant any material having a transparent or translucent visual effect as defined herein above. This transparency of the material makes it possible to provide a backlighting function (r tro) on the body part, since the transparent region passes light from a light source arranged behind the body part. The light projected through this transparent region can enhance the image that the manufacturer wishes to associate with his vehicle model, or often provide visual information to the user from outside the vehicle at the request of the manufacturer's designer.

The advantages of the method as proposed by the present invention are: the simultaneous molding of two materials using existing standard molds without any mechanical means to distinguish the regions of each material (e.g., a mold with a gate or a rotary mold) reduces the cost and time of producing a bi-material product.

According to different embodiments corresponding to the manufacturing method, the following optional features can be adopted, alone or in combination:

-the method comprises the following steps taken alone or in combination: applying a mask to a predetermined area on the whole or part of the vehicle body member; painting the whole body part; and taking down the mask. The step of applying the mask allows the entire part to be sprayed with less precision and therefore at a faster rate, while protecting the transparent area from paint splatter.

The manufacturing method as proposed by the invention is particularly advantageous for manufacturing different series of bodywork products. For example, for body parts for entry-grade vehicles that do not require any backlit area, only opaque material is injected during molding to obtain a completely opaque part, and then the part is entirely painted without any masking step; for body parts for medium end vehicles, a small amount of transparent or translucent material may be injected simultaneously with the opaque material to obtain a part having a relatively small portion of transparent or translucent area, and masking and painting the small backlit area; for body parts for higher end vehicles, a larger backlight area may be achieved by injecting more transparent material or injecting transparent material at multiple locations. Therefore, the method can realize parts with various styles based on a single mold, and is simple, quick and low in cost.

The step of applying the mask consists in masking the predetermined areas that should not receive paint to let the backlight light pass before painting. This is generally achieved by arranging an adhesive film which can be pre-cut into the exact shape of the non-painted area to be obtained. Once the painting step is complete, the mask can be easily removed. The predefined area remains unpainted and transparent.

-the method comprises the steps of: painting the whole body part; by means of the laser beam, the lacquer is removed in a predetermined area on the whole or part of the body part. This method, called "laser shaving", enables very precise profiles to be obtained for transparent areas. This alternative is particularly advantageous for achieving unpainted areas of small size or having complex shapes and contours.

The predetermined area is located at least partially, preferably entirely, in the transparent portion of the moulded body part. Masking the predetermined area before painting or scraping with a laser after painting makes it possible to obtain an unpainted area smaller than the area of the transparent portion. The shape of the predetermined area can be easily changed for a given area of the transparent area, since only the shape of the mask or the set path of the laser beam needs to be changed.

-the mould is connected to a plurality of injection nozzles controlled to carry out a series of programmed injection operations, the injection nozzles being mutually spaced at a distance of at least 10mm and connected to containers containing different materials. Thus, the injection nozzles are uniform and can be independently manipulated. This makes it possible to vary the position of the meeting line of the two material fronts, depending on the size and/or the arrangement (position) of the transparent zones provided. The mold is opened when all injections are completed. In order to accurately adjust the injected mass, it is preferable to have a separate feed unit with a specific injection capacity for each material being injected. There may be a program for feeding the first material and a specific program for feeding the second material. However, for reasons of repeatability in the position of the joining line between the two materials, it is preferable to use the same procedure for the feed supply of the two materials. Thus, it is feasible and easy to produce a part comprising transparent areas by using a mould originally designed for a single material part.

The method comprises the step of determining the order in which each injection nozzle is opened and closed, and the quantity of material injected. This step makes it possible to adjust the ratio between the two materials to be injected to obtain a part with satisfactory transparent areas and at the same time to satisfy the requirements in terms of impact resistance, when the strength of the injected material is less than the other.

The shape and size of the transparent zone can be easily modified, for example according to the shape and size variations of the predetermined zone to be achieved, since it is only necessary to change the opening and closing sequence of the injection nozzle in order to change the development area of the transparent material with respect to the development area of the opaque material in the cavity.

For each new body part to be produced and the injection mould associated therewith, the injection nozzle is set to perform a synchronized opening and closing. They are also located in the cavity of the mould and therefore follow the position of the transparent zone. A prior rheology (rh logie) study must be performed to determine these positional and sequence parameters. Depending on the part to be realized and the mould used, a previous rheology study arranged the nozzles according to different variants of the transparent zone to be realized. With these determined nozzle positions, their synchronization can be varied to achieve different numbers or sizes of transparent regions.

-the first material is selected from: talc filled polypropylene (PP) EDDM, Polyamide (PA), Polycarbonate (PC), Acrylonitrile Butadiene Styrene (ABS), blends of Polycarbonate (PC) and Acrylonitrile Butadiene Styrene (ABS).

-the second material is selected from: translucent natural polypropylene, Cyclic Olefin Copolymer (COC), Polyethylene (PE), Polyamide (PA), Polycarbonate (PC), Acrylonitrile Butadiene Styrene (ABS), a mixture of Polycarbonate (PC), Acrylonitrile Butadiene Styrene (ABS), Polystyrene (PS) and Polymethylmethacrylate (PMMA).

The choice of first and second materials to be injected is not limited to the list of materials described above. On the other hand, materials may be selected that are compatible at their junction line when mixed (micro), cohesive, or fused in the mold cavity. Based on this criterion, the skilled person will be able to find a suitable combination of materials depending on the desired colour or transparency and appearance of the second region.

When the body part to be realized is a bumper, the injected first material will be opaque, generally black, since technical specifications, in particular regarding impacts, require the use of polypropylene (PP) EDDM filled with talc. The material will then be painted to have the desired color, most often the same color as the vehicle body. However, any other type of body member constructed of two transparent materials may be manufactured.

When the painted vehicle body part is smaller in size than the bumper, a transparent material may also be used as the first material. By thus utilizing the transparency of the first material and/or by locally molding it to have a smaller thickness, a backlit area through the paint is obtained which has a different appearance than the backlit area formed by the predetermined area of the second material which is not painted. The two materials may also have different colors to obtain further different variations in appearance.

The subject of the invention is also a body part obtained by the manufacturing method as described above. The components may be symmetrical or asymmetrical. The mass percentage of the second material in the vehicle body component is 0 to 30%, preferably 5 to 20%. The second material may be present in a plurality of distinct and unconnected areas, each possibly having a different appearance, for example two transparent areas made of Polycarbonate (PC) with different hues. In this case, the component has three different materials.

The subject of the invention is also a motor vehicle comprising at least one body part as described above.

Drawings

The invention will be better understood on reading the following description, provided by way of example only, with reference to the accompanying drawings:

FIG. 1 is a perspective view of a motor vehicle comprising a body component obtained according to the manufacturing method of the invention;

FIG. 2 is a front view of a body part obtained according to the molding step of the invention;

FIG. 3 is a front view of a painted vehicle body part having a transparent area according to a first variant;

fig. 4 is a front view of a painted vehicle body part with a transparent area according to a second variant.

Detailed Description

In fig. 1, a motor vehicle 100 is shown, which comprises a body part 1 according to an embodiment of the invention, which body part is a bumper.

According to a first variant, shown in figures 2 and 3, the bumper 1 is made of two different materials. The bumper 1 thus comprises a first region 10 of a first material, for example polypropylene (PP) EDDM filled with black talc, and two second regions 11 of a second material, for example translucent natural polypropylene. The mold for manufacturing the bumper according to the second modification includes one or more first material injection nozzles disposed near the first region and one or more second material injection nozzles disposed near the second region. Both materials are injected in the same molding step according to a predetermined injection program, keeping the mold closed.

Then, a mask (marouflag) is applied to the second region 11. Two sheets of film having a symmetrical shape are arranged in the second region 11 and held by the adhesive. The portion covered with the film corresponds to a predetermined area 12 which is not desired to be painted and transparent. Paint is applied to the bumper 1 and the film is then removed from the bumper.

After painting and removal of the film, a painted bumper 1 is obtained, except for the predetermined area 12 which remains transparent, as shown in fig. 3.

Fig. 4 shows a second variant of the invention, according to which the bumper 1 comprises a plurality of transparent zones, which are symmetrical or asymmetrical. In this variant, one or more additional nozzles are added in the mould to inject the second or third material in the central zone 11'. A mask is applied in the central area 11 'to obtain a new predetermined area 12' of a shape different from the other predetermined areas 12, which is not varnished and transparent.

The invention is not limited to the illustrated embodiments, other embodiments will be apparent to those skilled in the art. In particular, after the entire bumper has been painted, the transparency in these areas can also be obtained by laser scratching (grattagelaser) in the predefined areas 12.