FR2894865A1 - Moulded component, e.g. motor vehicle fixed window seal, is made from injected thermoplastic elastomer with overmoulded coating of lower friction material - Google Patents

Abstract

The moulded component (1), such as a seal for a fixed window (V) in a motor vehicle, is made from an injected material (2) based on a thermoplastic elastomer covering the edge of the window, with a coating (5) of a lower friction material that differs by being anchored in place by overmoulding. The overmoulding is in the form of an insert with a T or L-shaped cross-section, with a top that forms an outer covering and a leg (6) that anchors it in place.

Description

MOLDED PIECE, METHOD FOR MANUFACTURING SAME, SEALING TRIM

  IS CONSTITUTED AND SEALING MODULE INCORPORATING IT.

  The present invention relates to a composite molded part intended for mounting on a fixed element, such as a fixed quarter glazing of a motor vehicle, a method of manufacturing the said piece, a seal constituted of said piece and destinee constituting a vertical strand before a fixed quarter glazing seal, and a sealing module comprising in combination said sealing gasket and a movable sliding seal glazing type sliding frame cache. In general, three large families can be distinguished from glazing joints or slides that provide a seal between a window and a door frame of a motor vehicle, namely the U-shaped straight section slides. , the single-leaf slides and the hidden frame slides. A concealed frame slider is usually based on extruded rubber, such as an ethylene / propylene / diene terpolymer (EPDM) or a thermoplastic elastomer derived from a blend of a polyolefin and a non-reticle or crosslinked elastomer (ie corresponding respectively to the usual abbreviations TPO or TPV, or TPO means polyolefin thermoplastic elastomer TPV and TPV vulcanisat thermoplastic), and this slide comprises in a known manner: - a U-shaped cross section fastener which has first and second parallel branches rune I and which is fitted to a door frame, said clamp being reinforced by a metal frame, - a main leg and an asymmetrical secondary leg which both extend said first branch substantially at right angles away from said second branch and which are equipped with sealing lips towards their respective ends, and 2 - two additional sealing lips which extend to two opposing said legs from said second leg and which are intended to provide a dual sealing function. Such a hidden frame slider is designed to have a flexibility which allows it to be deformed so as to adapt it to the shape of the door frame on which it is slid. Patent document US Pat. No. 5,261,721 discloses a sealing lining for fixed quarter glazing of a motor vehicle, in which is anchored a support connecting this lining to a fixed joint which is integral with the bodywork. This lining is for example based on polyvinyl chloride or a polyurethane mold. Vehicles which have a fixed rear quarter glazing of a door specifically provided with a concealed frame slide must necessarily incorporate, on this quarter panel glazing, a seal 15 having a reduced coefficient of friction vis-a-vis screw of the rubber of the slide, in order to confer, at the same time, the wear and tear cycles of the slide and the door trim and to avoid the overturning, a satisfactory wear resistance to the respective contact surfaces of the slide and the quarter panel trim; sealing lips of the slide in contact with this liner. The quarter panel liner on which is intended to come into contact with a concealed frame slider is usually based on a molded thermoplastic elastomer, which is preferred to polyvinyl chloride and polyurethane for reasons of environmental preservation and also because of the relatively dull colors it can provide like the surrounding rooms. However, because the thermoplastic elastomers chosen generally have a high coefficient of friction with EPDM or with TPO or TPV optionally used in these slides, it is nowadays possible to manually deposit a adhesive coating of the film type on the quarter panel of thermoplastic elastomer, this adhesive coating having a reduced coefficient of friction vis-à-vis the EPDM or TPO or TPV. A major disadvantage of this current solution resides in particular in its relatively high cost of implementation.

  An object of the present invention is to provide a molded part intended to be mounted on a fixed element, such as a quarter glass of a motor vehicle, said piece comprising an injected material which is adapted to coat said fixed element and which is based on at least one thermoplastic elastomer and further comprising a coating which has a coefficient of friction lower than that of said material vis-à-vis a same rubber selected from the group consisting of terpolymers ethylene / propylene / diene (EPDM), thermoplastic polyolefin elastomeres (TPO) and thermoplastic vulcanizates (TPV), which overcomes the aforementioned drawback.

  For this purpose, a molded part according to the invention is such that said coating is anchored in said material by overmolding.

  It will be noted that this anchoring of the coating with a reduced coefficient of friction in the body of the molded part, such as a sealing gasket for rear quarter glazing, makes it possible to significantly reduce the manufacturing cost of this piece, in comparison with the seal linings for glazing custodium known that require the manual deposition of the adhesive film after molding. According to another advantageous feature of the invention, said coating is obtained by overmolding an insert with said coating material, said insert having a substantially T-shaped or r-shaped cross-section, the top of which forms said coating and whose the leg forms an anchor tab of said insert in said coating material.

  Preferably, said coating is based on at least one polymer selected from the group consisting of polypropylenes, acrylonitrile resins, polycarbonates, polyamides, polyoxymethylenes (POM) and mixtures thereof. Even more preferentially, said coating is based on at least one resin based on acrylonitrile, such as an acrylonitrile / butadiene / styrene resin (resin known under the name ABS) or an alloy of an acrylonitrile / butadiene resin / styrene and a polycarbonate (this alloy is usually known as ASA). It should be noted that these materials that can be used for said coating are particularly advantageous for imparting to the molded part, such as a fixed quarter-glass glazing seal, a reduced coefficient of friction - and therefore improved wear resistance - -a-vis a mobile stanchion seal in EPDM, TPO or TPV slide type cache frame.

  Indeed, the Applicant has been able to verify that the use of such materials and more particularly of the aforesaid ASA alloy makes it possible to significantly delay the wear of the respective contact surfaces of the slide and the quarter panel trim. avoid overturning of the slats of the slider, despite the extremely frequent cycles of breakdown / door opening occurring on the vehicle considered.

  Also preferentially, said coating material is based on a thermoplastic elastomer which is derived from a polyolefin and which is of the TPO or TPV type and, even more preferably, of the TPV type comprising a mixture of: crosslinking elastomer, which is synthesized by a metallocene catalyst and which belongs to the group consisting of ethylene / propylene / diene terpolymers (EPDM) and polyoctenes, and - a polyolefin graft. Even more preferentially, said thermoplastic elastomer is a mixture of an EPDM reticulated and synthesized by a metallocene catalyst and a polypropylene, this thermoplastic elastomer being then for example known under the name << VEGAPRENE D.

  A method of manufacturing a composite part according to the invention is such that it comprises: (i) inserting an insert into an injection mold, (ii) injecting said mold into said mold on said insert, for obtaining by overmolding a partial coating of said insert, and (iii) cooling said injected material for obtaining, by extraction of said mold, said anchor coating in said material via a tab of anchoring that comprises said insert.

  According to another characteristic of the invention relating to the manufacture of a waterproofing lining intended to form a vertical strand before a seal of said quarter glass, said method comprises, prior to step (i), placing the quarter glass in said mold, said coating obtained in step (ii) above having a cavity of rectangular section parallel to said anchoring tab which encloses said glazing. said insert set up in step (ii) is advantageously in one piece (ie monobloc) and it has through holes in said anchoring tab, to allow the passage of said injected material on either side of said tab so as to provide a satisfactory holding or adhesion of the rinsed coating, it should be noted that these orifices provided in said insert make it possible to dispense with prior adhesion treatment with the insert / injection coating interface, It further contributes to reducing the manufacturing cost of the filling according to the invention.

  A molded seal according to the invention is specifically intended to constitute a vertical strand prior to a fixed quarter glazing seal of a motor vehicle, said gasket comprising an injected coating material which is suitable for coating said quarter glass and which is based on at least one thermoplastic elastomer and also comprising a coating having a coefficient of friction lower than that of said material vis-à-vis a same rubber selected from the group consisting of ethylene / propylene / diene terpolymers (EPDM), polyolefin thermoplastic elastomeres (TPO) and thermoplastic vulcanizates (TPV). According to the invention, this seal is such that said coating is anchored in said overmolding coating material. .

  According to another advantageous feature of the invention, said coating is obtained by overmolding an insert with said coating material, said insert having a cross-section substantially T-shaped or r-shaped over all or part of its length, of which the top forms said coating and whose leg forms an anchor tab of said insert in said material, which extends under said crown by embedding said anchoring tab via through orifices formed in the latter to allow the passage of this material injected. According to another characteristic of the invention, a cavity of rectangular section adapted to grip said glazing is formed in said coating material parallel to said anchoring tab. According to another advantageous feature of the invention, said insert comprises at the location of said anchoring tab means adapted to bear on said quarter panel glazing which are formed in one piece with said insert and which open into said level cavite 25 with said coating material. Advantageously, said support means comprise ribs extending over all or part of the length of said gasket, in a plane substantially perpendicular to that of said coating. According to another advantageous feature of the invention, said insert further comprises at the location of said anchoring tab fastening means provided for fixing said lining to a bodywork of said vehicle facing said glazing, said fixing means being integrally formed with said insert Advantageously, said fixing means are adapted to snap onto the edge of at least one orifice formed in said body, and they comprise for example, at the two respective ends of said lining, two clipping pins formed projecting from said anchoring tab a '' opposes said support means, it will be noted that said insert uses to obtain the quarter panel trim according to the invention (the present invention has the advantage while being monobloc and homogeneous). (ie based on one and the same material), to integrate at the same time: - an anti-wear function with respect to the friction generated by the material EPDM, TPO or TPV of the hidden frame slide, via said rev and, - an indexing function (i.e. positioning) on the body of the rear quarter panel formed by said glazing and said liner, via said fastening means for example claw type pins. According to another characteristic of the invention, said lining may be provided with at least one lateral stop (ie in the transverse direction of the vehicle) which is attached to said coating material and which is intended to be mounted in abutment on the body of said vehicle facing said glazing. According to an alternative embodiment of the invention, it should be noted that said insert according to the invention could also integrate one or more lateral stop (s) formed (s) integral with said anchor tab, in more than the aforementioned fixing means. As indicated above with reference to said molded part according to the invention, said injected coating material is based on at least one thermoplastic elastomer derived from a polyolefin, and said coating is based on at least one polymer selected from the group consisting of polypropylenes, acrylonitrile resins, polycarbonates, polyamides, polyoxymethylenes (POM) and mixtures thereof.

  Preferably, said coating material is based on a thermoplastic vulcanizate thermoplastic elastomer (TPV) comprising a mixture of: - a crosslinked elastomer, which is synthetized by a metallocene catalyst and which belongs to the group constituted by the ethylene / propylene / diene terpolymers and polyoctenes, and grafted polyolefin, such as polypropylene. Also preferentially, said coating is based on at least one acrylonitrile-based resin, such as an acrylonitrile / butadiene / styrene resin (ABS) or an alloy of an acrylonitrile / butadiene / styrene resin and a a polycarbonate (ASA alloy).

  A waterproofing module for a motor vehicle according to the invention is of the type comprising: a sealing gasket intended to constitute a vertical strand before a fixed quarter glass glazing seal of said vehicle, and a sealing gasket. A sliding frame-type sliding frame adapted to come into contact with said sealing gasket According to the invention, this sealing module is characterized in that said sealing gasket is as defined above. Another feature of the invention is that the waterproofing seal comprises: a U-shaped cross-section fastening clip having first and second parallel arms (one to one); other, 25 - an asymmetric main leg and a secondary leg which both extend said first branch substantially at right angles away from said second leg and which are equipped with sealing lips towards their ends; and two additional sealing lips which extend both opposite said legs from said second leg and which are intended to provide a double sealing function in contact with said sealing gasket.

  According to another feature of the invention, said mobile seal is based on a rubber selected from the group consisting of ethylene / propylene / diene terpolymers (EPDM), polyolefin thermoplastic elastomeres (TPO) and thermoplastic vulcanizates. (TPV).

  Other features, advantages and details of the present invention will become apparent on reading the following description of several embodiments of the invention, given by way of nonlimiting illustration, said description being made with reference to the accompanying drawings, among others. 1 is a schematic plan view of a fixed quarter glazing provided with a seal according to the invention forming a vertical strand prior to the rear quarter seal, FIG. 2 is a transverse cross-sectional view of FIG. a movable seal forming a top strand of a concealed frame slider and usable according to the invention for co-operation with the packing of FIG. 1, FIG. 3 is a cross-sectional view along the III-III plane of FIG. FIG. 1 of said sealing gasket according to an exemplary embodiment of the invention, and FIG. 4 is a cross-sectional view along the plane IV-IV of FIG. 1 of the sealing gasket according to the example of FIG. e Figure 4.

  The fixed quarter glazing V illustrated in FIG. 1 presents in a conventional manner a geometry substantially in the shape of a rectangular trapeze whose large base AB is provided with a sealing gasket 1 according to the invention (forming a vertical vertical strand before I). whole of the rear quarter seal (not shown) By way of example and in no way limiting, this large base AB of the glazing V is equipped with a lining 1 of length equal to 348 mm, this glazing V being, for example, of the laminated type and being further characterized by a thickness of about 3.9 mm, a small curved CD base of 227 mm length and BC and AD distances of 397 mm and 369 mm, respectively. schematically, on the one hand, a coating 2 of the lining 1 which is mounted in contact with the two inner faces V and external Ve of the glazing V (see Figures 3 and 4) and, secondly, two fixing means 3 of this coating 2 on the bodywork C of a motor vehicle ( represented in the following figures). The movable seal 10 illustrated in FIG. 2 forms a top strand of a concealed frame slider. In a known manner, this seal 10 is based on at least one EPDM, TPO or TPV type elastomer, and it comprises: a U-shaped cross-section fastener 11 which is fitted on a door frame 12 and in which is embedded a metal armature 13, also of U-section, to reinforce the holding of the clamp 11, - a main leg 14 and a secondary leg 15 asymmetrical both extending a first branch 11a of the clamp 11 substantially a right angle away from a second branch 11b thereof and which are equipped with sealing lips 16 to their respective ends, these lips 16 being able to come in sliding contact with the two faces of a glazing V 'of the door equipped with this seal 10, and - two additional sealing lips 17 which extend both at the opposite of the legs 14 and 15 from the second leg 11 b and which are destined to come in contact with the seal 1 according to the invention. This seal 1, which is illustrated in Figures 3 and 4, is a molded part which essentially comprises: - the coating 2 which has a rectangular cavity 4 to enclose the glazing V and which is formed by a material injected a base a thermoplastic elastomer, advantageously a TPV denomination VEGAPRENE)>, and - a coating 5 for example of ASA alloy which is anchored in the coating material 2 by overmoulding and which has a reduced coefficient of friction vis-à-vis EPDM, TPO or TPV of the mobile joint 10.

  This coating 5 is obtained via the following steps: (i) the glazing V is put into place in an injection mold, (ii) a homogeneous and integral insert I of cross-section is substantially positioned on the internal face of the glazing unit V T-shaped in the example of Figures 3 and 4, whose apex is intended to form the coating 5 and whose leg forms an anchor 6 in the coating material 2 which is parallel to the cavity 4 and which has through holes 7 to allow the passage of the injected material, (iii) is injected this coating material 2, such that it extends under the top 5 by coating the anchoring tab 6 via the openings 7, and (iv) cooling the coating material 2 to obtain, by extracting the mold, the anchor coating in the coating 2 via the anchoring tab 6.

As illustrated in FIGS. 3 and 4, the insert I comprises, at the location of the anchoring tab 6, ribs 8 adapted to bear on the internal face V of the glazing unit V and opening into the cavity 4 of FIG. level with the coating material 2, as well as the fixing means 3 25 (visible in Figure 4) which are intended to attach the lining 1 to the bodywork C of the vehicle facing the glazing V. As can be seen in FIG. 4, the fastening means 3 comprise, in this example of embodiment, two clipping pins 3 which are projecting on the anchoring tab 6, at the respective ends A and B of the lining 1 and opposite the ribs 8, and which are adapted to come snap on the edge Co of an orifice forms in the body C.

As illustrated in FIG. 3, the lining 1 is furthermore advantageously provided with a lateral stop 9a (ie in the transverse direction of the vehicle) which is attached to the cladding 2 and which is intended to be mounted in abutment. on the bodywork C opposite the glazing V. The final quarter panel P is finally obtained, following overmolding of the coating 2 on the glazing V and on the insert I, on the bodywork C of the vehicle via the fixing means 3 and the stop 9a, and this panel P is secured to the body C via a glue bead 9b applied to the inner face V; of glazing V. 10

Claims (25)

  A molded part (1) intended for mounting on a fixed element, such as a rear quarter glazing (V) of a motor vehicle, said part comprising an injected material (2) which is adapted to coat said fixed element and which is based on at least one thermoplastic elastomer and further comprising a coating (5) having a coefficient of friction lower than that of said material vis-a-vis a same rubber selected from the group consisting of ethylene terpolymers / propylene / diene (EPDM), thermoplastic polyolefin elastomeres (TPO) and thermoplastic vulcanizates (TPV), characterized in that said coating is anchored in said material by overmolding.   2. Piece (1) according to claim 1, characterized in that said coating (5) is obtained by overmolding an insert (I) by said coating material (2), said insert having a cross section substantially shaped T or R, whose top forms said coating and whose leg forms an anchor tab (6) of said insert in said material.   3. Piece (1) according to claim 1 or 2, characterized in that said coating (5) is based on at least one polymer selected from the group consisting of polypropylenes, acrylonitrile resins, polycarbonates , polyamides, polyoxymethylenes (POM) and their mixtures.   4. Part (1) 'according to claim 3, characterized in that (edit coating (5) is based on at least one resin based on acrylonitrile, such as an acrylonitrile / butadiene / styrene resin (ABS) or an alloy of an acrylonitrile / butadiene / styrene resin and a polycarbonate.   5. Piece (1) according to one of the preceding claims, characterized in that said coating material is based on a thermoplastic elastomer which is derived from a polyolefin.   6. Piece (1) according to claim 5, characterized in that said coating material is based on a thermoplastic elastomer thermoplastic vulcanizate type (TPV) comprising a mixture of: - a reticule elastomer, which is synthesized by a metallocene catalyst and which belongs to the group consisting of ethylene / propylene / diene terpolymers and polyoctenes, and a grafted polyolefin, such as polypropylene.   7. A method of manufacturing a composite part (1) according to one of the preceding claims, characterized in that it comprises: (i) the introduction of an insert (I) in an injection mold, (ii) injection into said mold of said material on said insert, for obtaining by molding a partial coating (2) of said insert, and (iii) cooling said injected material for obtaining, by extraction of said mold , said coating (5) anchored in said material via an anchor tab (6) that includes said insert.   8. Method according to claim 7, characterized in that it comprises, prior to step (i), the establishment of said quarter glass (V) in said mold, said coating (2) obtained at the step (ii) 25 having a cavity (4) of rectangular section parallel to said anchoring tab (6) which encloses said glazing, for obtaining after step (iii) of a seal (1) intended to constitute a vertical strand before a seal of said quarter glass. 30   9. Method according to claim 7 or 8, characterized in that said insert (I) set up in step (ii) is in one piece and presented through orifices (7) in said anchoring tab (6). ), to allow the passage of said injected material (2) on either side of said tab.   10. A molded seal (1) intended to form a vertical strand before a fixed quarter glazing seal (V) of a motor vehicle, said lining comprising an injected coating material (2) which is adapted for coating said quarter glass and which is based on at least one thermoplastic elastomer and also comprising a coating (5) having a coefficient of friction lower than that of said material vis-à-vis a same rubber selected in the ethylene / propylene / diene terpolymers (EPDM), thermoplastic polyolefinic elastomers (TPO) and thermoplastic vulcanizates (TPV), characterized in that said coating is anchored in said material by overmolding.   11. Gasket (1) according to claim 10, characterized in that said coating (5) is obtained by overmolding an insert (I) by said coating material (2), said insert (I) having a cross section substantially u-shaped T or r over all or part of its length, the top of which forms said coating and whose jamb forms an anchor tab (6) of said insert in said material, which extends under said top in embedding said anchoring tab.   12. Gasket (1) according to claim 11, characterized in that a cavity (4) of rectangular section adapted to enclose said glazing (V) is formed in said coating material (2) parallel to said anchor (6).   13. Gasket (1) according to claim 12, characterized in that said insert (I) comprises at the location of said anchoring tab (6) means (8) adapted to bear on said quarter glass ( V) 16 which are formed integrally with said insert and which open into said cavity (4) level with said coating material (2).   14. Gasket (1) according to claim 13, characterized in that said support means (8) comprise ribs extending over all or part of the length of said gasket, in a plane substantially perpendicular to that of said coating ( 5).   15. Gasket (1) according to one of claims 11 to 14, characterized in that said insert (I) comprises at the location of said anchoring lug (6) fastening means (3) provided for fixing said lining a body (C) of said vehicle facing said glazing (V), said fixing means being formed integrally with said insert.   16. Gasket (1) according to claim 15, characterized in that said fixing means (3) are adapted to snap on the edge (Co) of an orifice formed in said body (C).   17. Gasket (1) according to claims 13 and 16, characterized in that said fastening means (3) comprise, at the two respective ends (A and B) of said liner, two clipping pins projecting on said lug of anchoring (6) has opposed said support means (8).   18. Gasket (1) according to one of claims 10 to 17, characterized in that through openings (7) are formed in said anchoring tab (6) to allow the passage of said injected coating material (2) of both sides of said tab.   19. Gasket (1) according to one of claims 10 to 18, characterized in that it is provided with at least one lateral stop (9a) which is attached to said coating material (2) and which is intended to be 30montee bearing on the body (C) of said vehicle facing said glazing (V).   20. Gasket (1) according to one of claims 10 to 19, characterized in that said injected coating material (2) is based on at least one thermoplastic elastomer derived from a polyolefin, and in that said coating ( 5) is based on at least one polymer selected from the group consisting of polypropylenes, acrylonitrile resins, polycarbonates, polyamides, polyoxymethylenes (POM) and mixtures thereof.   21. Garniture (1) according to claim 20, characterized in that said coating material is based on a thermoplastic elastomer thermoplastic vulcanizate type (TPV) comprising a mixture of: - a reticule elastomer, which is synthetized by a metallocene catalyst and which belongs to the group consisting of ethylene / propylene / diene terpolymers and polyoctenes, and a grafted polyolefin, such as polypropylene.   22. Gasket (1) according to claim 20 or 21, characterized in that said coating (5) is based on at least one resin based on acrylonitrile, such as an acrylonitrile / butadiene / styrene resin (ABS) or an alloy of an acrylonitrile / butadiene / styrene resin and a polycarbonate. 25   23. Sealing module for a motor vehicle, comprising: - a sealing gasket (1) intended to form a vertical strand before a fixed quarter glazing seal (V) of said vehicle, and - a sealing gasket movable frame (10) having a frame frame 30 adapted to come into contact with said seal, characterized in that said seal seal is as defined in one of claims 10 to 22.   24. The waterproofing module as claimed in claim 23, characterized in that said movable seal (10) comprises: a U-shaped cross-section fastening clip (11) comprising first and second branches (11a); and 11b) parallel to each other, - an asymmetrical main leg (14) and a secondary leg (15) both of which extend said first leg (11a) substantially at right angles away from said second limb (11b). ) and 10 which are equipped with sealing lips (16) to their respective ends, and - two additional sealing lips (17) which extend both opposite (said legs (14 and 15) from said second leg (11b) and which are intended to provide a double sealing function in contact with said sealing gasket (1).   25. Sealing module according to claim 23 or 24, characterized in that said movable seal (10) is based on a rubber selected from the group consisting of ethylene / propylene / diene terpolymers (EPDM) , thermoplastic polyolefin elastomeres (TPO) and thermoplastic vulcanizates (TPV).