FR3093039A1 - Illuminated functional element for motor vehicle - Google Patents

Abstract

The invention relates to a method of manufacturing a luminous functional element for a motor vehicle, comprising (a) providing at least one optical fiber comprising a core and an optical cladding for containing light waves in said core, said cladding having undergone a treatment to degrade and / or roughen said optical cladding, (b) provide at least one polymer material, (c) separately heat each polymer material provided in step (b) to fluidify it and introduce it with said at least one optical fiber provided in step (a) in a non-circular die or in a mold, so as to obtain after cooling the functional element, the die or the mold having the section or the shape, respectively, of said element. Figure for the abstract: figure 1

Description

Luminous functional element for a motor vehicle

The subject of the invention is a functional element for a motor vehicle, in particular for covering and/or sealing, integrating at least one optical fiber emitting light.

This luminous element can be linear, and in particular profiled, and can for example comprise a door seal, a trunk seal, a window slider, a window weatherstrip, a double seal, a roof trim, a simple tube soft, or whatever.

An optical fiber comprises a glass or plastic core, surrounded by an optical cladding, usually of the same material as the core, to contain the light waves in the core. A protective plastic coating surrounds the optical sheath. It is also possible to provide gel on the periphery of the protective coating, and a cable sheath to protect the assembly.

Document US Pat. No. 7,082,721 describes a profile for a motor vehicle comprising a profiled body defining a housing, and a linear light-emitting element received in this housing.

There is a need for a functional element that is simpler to manufacture.

A method of manufacturing a luminous element for a motor vehicle is proposed, comprising

(a) providing at least one optical fiber comprising a core and an optical sheath to contain light waves in the core, said sheath having undergone a treatment to degrade and/or roughen said optical sheath,

(b) providing at least one polymeric material,

(c) separately heating each polymer material so as to fluidize it and introducing it with said at least one optical fiber into a non-circular die or a mold so as to obtain, after cooling, a functional element for a motor vehicle, the die or the mold having the section or shape, respectively, of this element.

This process is relatively simple to implement. The number of steps to be performed can be fewer, the interventions reduced and the logistics simplified, compared to the process of document US 7,082,721.

The treatment applied to the optical cladding can be a mechanical treatment, of the abrasion or sandblasting type, a chemical treatment, involving a solvent for example, an optical treatment, involving a laser for example, and/or other.

The treatment can for example lead to a reduction in the thickness of at least part of the optical cladding, to a modification of its composition, of its surface appearance, and/or other.

Due to the degradation provided, the light coming from a light source at one end of the optical fiber and propagating in the fiber can diffuse radially. The fiber can thus emit light over at least part of its length, which can offer interesting design possibilities for the realization of the luminous functional element.

For example, step (c) can be carried out so that said at least one optical fiber is at least partly located at an outer edge of the luminous element. This at least one optical fiber can thus, when illuminated at one end, be visible over at least part of its length.

The functional element can for example be a seal, or other.

In the case of a step (c) carried out by means of a die, the luminous element may be linear, with a profile corresponding to the section of the die. During step (c), each polymer material is extruded separately and the optical fiber(s) is introduced into the extrusion die with the polymer material(s) fluidized.

A linear element is then obtained comprising said at least one optical fiber extending along the longitudinal direction of the profile and embedded (over at least part of its periphery) in the polymer material(s), the die having a section corresponding to that of the linear element.

The linear element can be a profile, that is to say that the profile is identical over its entire length, or not, in particular in the case of a variable extrusion.

The linear element can be shaped to produce a covering and/or a seal (door seal, window slider, etc.) and/or to serve as an acoustic waveguide for the purpose of detecting impact or pinching (sensor tubular for example).

The linear element may for example have a section of which at least a part is tubular, in particular in the case of a joint or of a linear element of the waveguide type.

When the linear element has a tubular part, the die used in step (c) can have a tubular section, or alternatively be devoid of a tubular portion, in particular if an assembly step is provided downstream of the die so as to to make this tubular part.

In the case of a luminous element of the linear trim and/or sealing element type (door seal, window slider, window weatherstrip, boot seal, etc.), the trim element and/ or seal may have a shaped section so as to achieve the covering and/or the expected seal, for example with a U-shaped part, with a lip, or the like.

For example, the die used in step (c) can have a section of which at least a part has a lip profile, so that the linear element obtained has a lip over its entire length or at least over at least part of its length.

The section of the luminous linear element can for example be shaped to ensure attachment to a door frame.

In one non-limiting embodiment, the covering and/or sealing profile may also comprise at least one reinforcing element extending longitudinally, for example a metal insert (strip), a plastic insert, fibers of carbon, fiberglass, or other.

In one non-limiting embodiment, an adhesive and/or glue can be applied to the linear element, for example downstream of the die, or even by co-extrusion. This can be used for fixing the linear element to the motor vehicle, or even for assembly with at least one other element, for example an additional profile.

In the case of a step (c) carried out by means of a mould, the luminous element may comprise a molded element, for example a plastic support a few centimeters or decimeters long, for example less than two meters long .

The function of the molded functional element may be a sealing function.

The molded luminous functional element can for example be a seal element or a seal, for example an anti-dirt seal element, a rear panel seal, a seal between doors, or the like.

Step (c) then comprises an injection, bi-injections or multi-injections step.

The optical fiber(s) can simply be installed in the mold before the injection(s).

For example, in step (c), said at least one optical fiber provided in step (a) can be installed in a mold, then each polymer material provided in step (b) can be injected and fluidized into said mold, so as to obtain a molded functional element.

In addition to its primary function (e.g. sealing), the luminous functional element can be used for decorative, signaling and/or alarm purposes. In particular, it is possible to provide power to the optical fiber(s) only in certain situations, for example if an opening is open or even in the event of potential danger. This can for example allow third parties to better see a person opening his night safe. Also, an electric door equipped with a light profile can visually signal to people around that the door is closing, thus limiting the risk of pinching.

The core can be, for example, glass or plastic.

The optical sheath may for example be made of glass or plastic.

The optical fiber can advantageously be devoid of plastic, thus making it possible to withstand the sometimes relatively high temperatures used during the manufacture of the luminous element without degradation.

In particular, when the polymer material comprises rubber, the temperatures used during a subsequent vulcanization step can be relatively high.

These temperatures can be higher than 200°C, advantageously higher than 220°C, for example of the order of 240°C.

These temperatures may be below 500°C.

In another embodiment, it is possible in step (a) to provide at least one optical fiber comprising not only a core and an optical cladding, but also a plastic coating around the optical cladding, and optionally gel and/ or a cable sheath.

This plastic coating can be wrapped around the fiber once the optical sheath has been treated.

This plastic coating may be translucent, as well as any gel and/or cable sheath.

In one embodiment, several optical fibers can be provided.

Advantageously and without limitation, these optical fibers can be twisted.

Alternatively, the optical fibers can be parallel to each other.

The treatment can be carried out in such a way as to alter the optical cladding over its entire length or not.

For a portion of optical fiber length undergoing the treatment, the treatment can be carried out so that the degradation is uniform over the entire periphery, or not. For example, provision may be made to abrade only one side of the optical fiber, which may correspond to an angular range for example comprised between 30° and 120°.

The polymer material can advantageously comprise between 10% and 100% by mass of polymer molecules.

The polymeric material can for example comprise rubber or a thermoplastic.

The polymer material may for example comprise EPDM, (for “Ethylene Propylene Diene Monomer”), polypropylene, polyethylene, SBS (for “poly(styrene-butadiene-styrene)” and/or SEBS (for “ poly(styrene-ethylene-butadiene-styrene)”).

In particular, the polymer material may comprise more than 15% by mass of rubber or thermoplastic, advantageously more than 20% by mass.

In particular, the polymer material may comprise less than 80% by mass of rubber, advantageously less than 50%.

For example, the polymer material may comprise between 20% and 40% by mass of EPDM (for "Ethylene Propylene Diene Monomer").

When the polymer material comprises a thermoplastic, the thermoplastic molecules can represent for example between 50% and 100% of the mass of the polymer material.

In both cases (EPDM or thermoplastic), the polymer material may also comprise:

- between 0% and 40% by mass of carbon black, for example between 20% and 30% by mass of carbon black,

- between 0% and 40% by mass of chalk, for example between 20% and 30% by mass of chalk, and/or

- between 0% and 22% of plasticizers of the type used for door seals.

The polymer material may further comprise between 0% and 15% of additives of the type used for door seals.

It is possible in step (a) to provide this material in the form of a strip, in particular in the case of rubber, granules, powder, or the like.

"Functional element" means an extruded element with a cross-section making it capable of carrying out a function, for example covering and/or sealing, or, where appropriate, molded in a mold having a shape making it capable of perform a function within the motor vehicle.

There is proposed a luminous functional element for a motor vehicle, and comprising

a body obtained by extruding or injecting at least one polymeric material into a die of non-circular section or a mold respectively, and

a set of at least one optical fiber, each optical fiber of said set comprising a core and an optical cladding to contain light waves in the core, said optical cladding being treated so as to let escape at least a part of the waves optics on its periphery, each optical fiber being embedded over at least part of its periphery in at least one of said at least one polymer material(s) of the profiled or molded body.

A lighting system for a motor vehicle is proposed, comprising the luminous functional element described above and a control device capable of illuminating the set of at least one optical fiber.

Advantageously, the control device comprises processing means, for example a microcontroller, arranged to control the illumination of the clearance of at least one optical fiber only if certain conditions are fulfilled, for example only if an opening, for example a door , a tailgate, or the like, is open.

Advantageously, the control device is arranged to illuminate the game of at least one optical fiber in several ways, for example with different colors, different intensities, different flashing frequencies, etc.

Advantageously, the processing means can impose a type of illumination (color, intensity, etc.) chosen according to variable values, for example chosen according to the state of an opening (moving or immobile, in the process of opening or in the process of closing, open while the engine is off, open while the automobile is in motion, etc.).

The invention is now described with reference to the accompanying, non-limiting drawings, in which:

very schematically illustrates an example of a method according to one embodiment of the invention.

schematically shows a section of an example of profile according to one embodiment of the invention.

schematically shows a sectional view of an example of a mold for a functional element according to another embodiment of the invention, with a bundle of optical fibers already installed.

schematically shows a 90° sectional view of a part of the mold of FIG. 3A, with the same beam.

is a perspective view of an example of a mold part for a functional element according to one embodiment of the invention.

Identical references may be used from one figure to another to designate identical or similar elements.

With reference to FIG. 1, a polymer material is provided, for example in the form of granules 10, and the inlet 11 of an extruder 12 is fed with these granules.

The increase in temperature leads to fluidizing the polymer material, so that at the exit of the extruder 12, the fluid polymer material 13 is obtained.

A die 14 of non-circular cross-section receives as input on the one hand this fluidized polymer material 13, and on the other hand an optical fiber 15 coming from a coil 16.

To implement this installation, the person skilled in the art could, for example, take inspiration from an existing installation in which a die receives as input on the one hand a fluidized polymer material, and on the other hand reinforcing fibers of the type glass fibers, and replace these reinforcing fibers with one or more optical fibers.

The optical fiber 15 is special in that it has undergone a treatment leading to the degradation of the outer surface of its optical sheath.

This treatment can for example be a mechanical treatment, for example an abrasion.

In one embodiment, a core and a glass sheath can be provided, in particular when the polymer material contains rubber. It will thus be possible to subject the linear element obtained at the outlet of the die 14 to a vulcanization treatment involving relatively high temperatures, for example 240° C., without risking degrading the optical fiber.

In FIG. 1, only one optical fiber has been shown, but several could be provided. This plurality of optical fibers could be twisted, for example so as to form a strand, or not.

The fiber twist or bundle can be stored in a spool.

In Figure 1, only one extruder is shown, but several could be provided, each receiving a corresponding polymer material as input. The plurality of fluidized materials leaving the plurality of extruders are introduced into the die (co-extrusion), with the optical fiber(s).

For example, in a variant not shown, one extruder can receive as input a rubber strip capable of forming a compact material and another extruder can receive as input a rubber strip capable of forming a cellular material.

To return to FIG. 1, this method makes it possible to obtain a linear functional element for a motor vehicle, for example a seal 17, having at least one optical fiber 15 partially embedded in the polymer material.

This at least one optical fiber 15 can advantageously be located on the surface of the linear functional element (over at least part of the length of this linear functional element) in order to be visible despite the absence of transparency of the polymer material.

Referring to Figure 2, there is shown a linear functional element section 17 'according to one embodiment of the invention, here a seal with a U-shaped part 18, a tubular part 19 and a flexible lip 20.

The functional element 17′, for example a profile, further comprises a bundle 21 of about ten surface-treated optical fibers so as to let the light waves pass on their periphery.

This beam 21 extends parallel to the longitudinal direction of the section 17', normal to the plane of the sheet.

This beam is located on the periphery of joint 17', in order to be visible.

In this example, the seal 17' also includes an insert 22 reinforcing the U-shaped part 18.

In addition, small lips 23 have been co-extruded with the rest of the profile.

It is for example possible to provide three extruders, one for the U-shaped clamp made of compact material, the other for the parts 19, 20, and the third for the labia minora 23. The outputs of these extruders supply a die which also receives beam 21.

Referring to Figures 3A and 3B, there is shown a mold comprising two parts 31, 32 defining, in a conventional way, a molding space 33 when applied against each other.

A bundle 33 of treated optical fibers is placed at the bottom of part 32, so that at least one end of the bundle comes out of the molding space. In Figure 3B, showing only one of the mold pieces and the beam, both ends come out of the mold.

The mold may have a suitable shape (groove) so as not to damage the beam when the parts 31, 32 are pressed against each other.

Then an injection, bi-injection or multi-injection is carried out in order to fill the rest of the molding space with fluidized polymer material(s).

A molded and luminous functional element for a motor vehicle, for example a seal, is thus obtained.

Figure 4 shows an example of a mold part 32' for producing a functional element. Two optical fibers 33' have also been shown in order to show an example of a possible location, but this part 32' could be redesigned in order to define grooves not shown in FIG. 4 to receive the ends of the optical fibers 33', in order to that these optical fibers 33' are not crushed when the part 32' is pressed against a similar part.

Claims (11)

Method of manufacturing a luminous functional element for a motor vehicle, comprising
(a) providing at least one optical fiber comprising a core and an optical sheath to contain light waves in said core, said sheath having undergone a treatment to degrade and/or roughen said optical sheath,
(b) providing at least one polymeric material,
(c) separately heating each polymer material provided in step (b) to make it fluid and introducing it with said at least one optical fiber provided in step (a) into a non-circular die or into a mold, so to obtain after cooling the functional element, the die or the mold having the section or the shape, respectively, of said element. A method according to claim 1, wherein in step (c),
each polymer material provided in step (b) is extruded separately to make it fluid, and
introducing said at least one optical fiber provided in step (a) with said at least one extruded polymer material, into a non-circular die, so as to obtain a linear functional element with a profile corresponding to the section of the die. A method according to claim 2, wherein step (c) is carried out such that the linear functional element is a profile. Method according to one of Claims 2 or 3, in which the die used in step (c) has a section of which at least part is tubular, so that the linear element obtained has a tubular profile. Method according to any one of Claims 2 to 4, in which the die used in step (c) has a section of which at least a part has a lip profile, so that the linear element obtained has a lip on at least part of its length. Method according to claim 1, in which in step (c), said at least one optical fiber provided in step (a) is installed in a mold, then said at least one polymer material provided in step is injected. (b) and fluidized in said mold, so as to obtain a molded functional element. A method according to any of claims 1 to 6 wherein step (c) is conducted such that at least one optical fiber is located at an outer edge of the luminous functional element. A method according to any of claims 1 to 7, wherein at least one optical fiber provided in step (a) is plastic free. A method according to any of claims 1 to 8, wherein the polymeric material provided in step (b) comprises EPDM, polypropylene, polyethylene, and/or SEBS. Method according to any one of claims 1 to 7, in which in step (a), a plurality of optical fibers twisted together are provided. Luminous functional element for a motor vehicle, comprising
a body obtained by extruding or injecting at least one polymeric material in a non-circular die or in a mold, respectively, and
a set of at least one optical fiber, each optical fiber of said set comprising a core and an optical sheath to contain light waves in the core, said sheath being treated to allow at least part of the waves to escape onto the periphery light, each optical fiber being embedded over at least part of its periphery in at least one of said at least one polymer material of the profiled or molded body, respectively.