FR2869005A1 - Dashboard for motor vehicle, has upholstery covering external side of support frame and having protrusions for fixation to frame, where protrusions are enclosed in frame following removal of material from frame during cooling - Google Patents

Abstract

The dashboard includes a rigid support frame (5) and flexible upholstery (7). The flexible upholstery covers an external side (9) of the support frame and comprises of protrusions (31) for fixation to the rigid support frame. The fixing protrusions are enclosed in the support frame following the removal of a material from the support frame at the time of cooling. Independent claims are also included for the following: (A) a process for manufacturing a dashboard for a motor vehicle (B) a motor vehicle.

Description

The present invention relates to a piece of equipment for a vehicle

automobile, of the type comprising:

  - a rigid support frame; - A flexible lining covering an outer face of the support frame and comprising at least one projection for attachment to the support frame.

  The invention applies for example to the dashboards of motor vehicles.

  From DE 44 46 484, a dashboard of the aforementioned type is known. The lining of such a dashboard comprises a plurality of fixing projections. Each projection is provided with a receiving orifice of a corresponding fixing pin mounted on the frame.

  The lugs are movable in translation relative to the armature, between a free position and a position engaged in the receiving orifice.

  Such a dashboard does not give complete satisfaction. Indeed, the fixing lugs are necessary to ensure proper fixing of the lining on the frame. Moreover, these pins must be inserted into each projection, which is difficult and expensive.

  The invention therefore aims to provide a piece of motor vehicle equipment, wherein the attachment between the frame and the flexible lining is made cheaply and simply.

  For this purpose, the object of the invention is a piece of the aforementioned type, characterized in that the attachment projection is gripped in the support frame following removal of the material of the support frame during cooling.

  The part according to the invention may comprise one or more of the following characteristics, taken alone or in any technically possible combination: the support frame comprises, for each attachment projection, a bearing face defining a receiving passage of the fixing projection, the bearing face enclosing the fixing projection; the support armature comprises a body and at least one wall projecting from the body, the bearing face belonging to the projecting wall, the projecting wall being movable, under the effect of the withdrawal, between a position insertion of the fixing projection and a clamping position of. the fixing projection; the protruding wall has a length substantially greater than at least 1.5 times the thickness of the body; - The body has, in a portion adjacent to the projecting wall, a hollow which opens towards the inner face of the body; the reception passage of the projection converges with an angle of between 0 and 60; and - the flexible lining comprises a plurality of bearing projections bearing on the outer face of the support frame, the length of the fixing projection being greater than the length of the adjacent bearing projections.

  The invention further relates to a method for producing a part as defined above, characterized in that it comprises the steps of: - heating the support frame; - insertion of the fixing projection in the support frame; - Cooling the support frame so that it grips, by removal of its material, the attachment projection.

  The method may include the following feature: - The step of heating the support frame has been obtained by molding the support frame.

  The invention also relates to a motor vehicle, characterized in that it comprises a piece of equipment as defined above.

  The invention will be better understood on reading the description which will follow, given solely by way of example, and with reference to the appended drawings, in which: FIG. 1 is a schematic, partial and perspective view of part of a dashboard of a motor vehicle according to the invention; Figure 2 is a schematic and enlarged section taken along the plane II-II of Figure 1; Figure 3 is an enlarged schematic view of the circled portion III of Figure 2; - Figure 4 is a schematic and partial section of a mold for making the armature of the dashboard of Figure 1; and - Figure 5 is a view similar to Figure 3 illustrating a step of the method of producing the dashboard of Figure 1.

  In all that follows, the terms "lower" and "higher" refer to the position of a driver of the motor vehicle.

  The terms "inside" and "outside" mean for themselves in relation to the dashboard 1.

  Figures 1 and 2 illustrate a dashboard 1 according to the invention. This board 1 comprises a rigid support frame 5, a flexible lining 7 covering the outer face 9 of the support frame 5, and means 11 for fixing the lining 7 to the support frame 5, visible in FIG. 2 .

  The support frame 5, sometimes called insert, is conventionally fixed to the body (not shown) of the motor vehicle. It is made for example of polyolefin thermoplastic material, homopolymer or copolymer, optionally comprising mineral fillers or a reinforcement with glass fibers, or for example ABS-PC (Acrylonitrile-Butadiene-Styrene and Polycarbonate) optionally reinforced with glass. These materials have a rigidity to fulfill a support function.

  The support frame 5 is curved to give the dashboard 1 its shape.

  The flexible lining 7 comprises an external covering skin 17 extended towards the inside of the board 1 by a network of supporting ribs 19 delimiting between them cells 21.

  The lining 7, and therefore the skin 17 and the ribs 19, are formed in one piece of plastic, for example elastomeric thermoplastic such as thermoplastic polyurethane (TPU), thermoplastic polyolefin (TPO). It is also possible to use flexible polyvinyl chloride (PVC) or rubber such as silicone. The lining 7 is significantly softer than the frame 5.

  The material used to form the lining 7 of Figures 1 to 2 is for example translucent as shown in Figure 1.

  Thus, an observer can distinguish the ribs 19 from outside the dashboard 1 through the skin 17. To facilitate the representation, the lining 7 has been shown opaque in Figures 2, 3 and 5.

  The ribs 19 extend from the inner face 23 of the skin 17 to the outer face 9 of the armature 5 on which they rest. Note that, in this example, the ribs 19 are substantially orthogonal to the direct surfaces of the frame 5 and the skin 17.

  The lining 7 being made of a flexible material and the cells 21 being delimited between the ribs 19, the lining 7 can be deformed to the touch.

  This deformation can result from a buckling of the ribs 19 situated in the vicinity of the point of application of a thrust force and a flexion of the region or regions of the skin 17 located (s) between these ribs 19.

  The ribs 19 and the deformation cells 21 thus give its flexibility and its thickness to the lining 7 so that a satisfactory comfort is obtained.

  The fixing means 11 comprise a plurality of fastening projections 31 integral with the skin 17, and, for each fixing projection 31, a gripping wall 33 integral with the frame 5 and delimiting an insertion passage 35 of the projection 31. The fastening means 11 further comprise a peripheral fixing assembly 37.

  In the example illustrated in Figures 2 and 3, the fixing projections 31 are integral with the skin 17. These projections 31 are constituted for example by blades which each extend inwardly through the frame 5, substantially orthogonal to the directing surface of the skin 17, from the inner face 23 of the skin 17 and to a free end 39.

  The projections 31 are distributed on the inner face 23 of the skin 17. As illustrated in FIG. 2, the lining 7 comprises, in section along a transverse plane, an alternation of support ribs 19 and fixing projections 31.

  Moreover, the length of the projections 31 between the inner face 23 of the skin 17 and their free ends 39, is greater than the length of the adjacent ribs 19.

  In the example illustrated in FIG. 2, the length of the projections 31 is, for example, greater than three times the length of the ribs 19.

  The fastening projections 31 also have a shape converging towards the outside of the skin 17, with a clearance angle of between 0.5 and 5.

  In the example illustrated in FIGS. 2 and 3, the clasping walls 33 are integral with the frame 5. Each clasping wall 33 projects inwards with respect to the body 34 of the frame 5 from the inner face 40 of the frame 5.

  The length of the clasping walls 33, measured between the inner face 40 of the armature 5 and the free ends 41 of the walls 33, is greater than at least 1.5 times the thickness of the body 34 of the armature 5.

  As illustrated in FIG. 3, each clasping wall 33 has an internal support face 45 on the corresponding projection 31 and an external face 47.

  The internal faces 45 delimit the insertion passages 35 of shapes substantially corresponding to the projections 31.

  These passages 35 open, on the one hand, into the outer face 9 of the armature 5 and, on the other hand, into the free ends 41 of the clasping walls 20.

  When the lining 7 is fixed on the frame 5, the inner face 45 of each wall 33 bears against the attachment projection 31 inserted in the corresponding insertion passage 35.

  Moreover, a hollow 49 is formed in the armature 5 in the extension of the outer face 47 of each wall 33. This hollow 49 has a substantially U-shaped cross section opening towards the internal face 40 of the armature 5.

  As will be described in detail below, each wall 33 is movable, under the effect of the removal of the material which constitutes the armature 5 during a cooling of this material, between an insertion position, shown in FIG. 5, and a clasping position, shown in Figure 3.

  In the insertion position (FIG. 5), the clasping wall 33 has generatrices substantially orthogonal to the directing surface of the body 34 of the armature 5. The passage 35 then has transverse dimensions greater than that of the projection of corresponding attachment 31.

  In the clasping position (FIG. 3), the generatrices of the wall 33 are inclined relative to the normal to the directional surface of the body 34, at an angle of between 0 and 60, preferably not zero, and for example equal to at 5 . In other words, the passage 35 converges towards the inside of the dashboard 1 with an angle between 0 and 60.

  This inclination of the wall 33 allows the contact between the inner face 45 and the projection 31, the wall 33 thus forming a clamp for fixing the projection 31.

  When the length of the fixing projection 31 and the gripping wall 33 is increased, the inclination of the wall 33 is correspondingly reduced in the gripping position.

  With reference to FIG. 2, the peripheral fixing assembly 37 comprises ratchet flanges 61 integral with the ribs 19 situated at the edge of the skin 17 and received in grooves 63 of complementary shapes formed in the edges of the skin. frame 5.

  An example of a method of producing the dashboard according to the invention will now be described. This method is in particular implemented using a mold 101 for forming the reinforcement 5 shown in FIG. 4. Only a part making it possible to make a wall 33 will be described later, but the mold 101 includes similar parts for each wall 33 to be formed.

  As illustrated in FIG. 4, the mold 101 comprises an upper half-mold 103 and a lower half-mold 105.

  The upper half-mold 103 is provided with a metal blade 107 which protrudes towards the lower mold half 105.

  The lower half-mold 105 has an upper face 109 comprising two bosses 111, and a cavity 113 for forming the clasping walls 33, formed laterally in the upper face 109 between the two bosses 111, opposite the blade 107.

  This cavity 113 is delimited by two lateral walls 115 substantially orthogonal to the upper face 109.

  The upper half-mold 103 is movable relative to the upper half-mold 105 between an open position of the mold 101 in which the blade 107 is away from the lower half-mold 101 and a closed position of the mold 101 in which the blade 107 is in contact with the bottom 117 of the cavity 113.

  When the mold 101 is in the closed position, the upper and lower half-molds 103 and 105 define a mold cavity of shape conjugate to the frame 5.

  The upper and lower half-molds 103 and 105 are also provided with cooling means (not shown).

  The method of producing the dashboard 1 comprises a step of supplying the lining 7, a molding step of the armature 5 in the mold 101 shown in FIG. 4, a step of laying the lining 7 on the armature 5 , and a step of fixing this lining 7 on the frame 5.

  Initially, the step of providing the lining 7 comprises for example a production step in which it is molded, in particular by injection of a resin in a mold of conjugate form, and then cooled.

  In the molding step of the armature 5, the material constituting the armature 5 is for example heated to temperatures between 180 ° C. and 300 ° C. and then injected into the molding cavity of the mold 101 in the closed position.

  The lower half-molds 103 and upper 105 are then cooled to harden this material.

  Given the shape of the mold 101, the cooling of the blade 107 of the upper half-mold 103 is slower than that of the side walls 115 of the forming cavity 113. As a result, the temperature of the inner face 45 of the Closing wall 33, in contact with the blade 107, is greater than the temperature of the outer face 47 in contact with the side wall 115 of the lower mold half 105.

  The mold 101 is then open and the armature 5 is extracted from the mold 101.

  At this time, the temperature of the inner face 45 is for example between 50 C and 80 C, while the temperature of the outer face 47 is between 30 C and 50 C.

  In the insertion step, the support ribs 19 are placed against the upper face 9 of the armature 5 and each attachment projection 31 is inserted into a corresponding insertion passage 35.

  Initially, at the outlet of the mold 101, the clasping walls 33 are in their insertion position, illustrated by FIG.

  In the fixing step, and under the combined effect of the temperature difference between the inner face 45 and the outer face 47 of each clasping wall 33, the shape of these walls 33, and the presence of the hollow 49 formed in the armature 5, the clasping wall 33 moves from its insertion position to its clasping position during the cooling of the material constituting the armature 5.

  This displacement is only performed under the effect of the differential shrinkage of the material which constitutes the wall 33.

  In the clasping position, each fixing projection 31 is pinched by the corresponding wall 33, and the lining 7 is then fixed firmly to the armature.

  In order to carry out the molding of the reinforcement 5 and the lining 7 shown in FIG. 2, the molds used comprise several wedges to ensure the respective demolding of the walls 33 and the projections 31.

  Thus, as a variant, all the projections 31 extend substantially parallel to a common direction, in order to simplify the structure of the mold which makes it possible to produce the lining 7. In this variant, the insertion passages also all extend substantially. parallel to a common direction in order to simplify the structure of the mold which makes it possible to produce the frame 5.

  Thanks to the invention that has just been described, it is possible to have a piece 1 of motor vehicle equipment in which the attachment between the frame 5 and the flexible packing 7 does not require the establishment of additional parts, which reduces its cost of implementation.

  Furthermore, the attachment between the frame 5 and the lining 7 can be made at the end of the molding of the frame 5, which simplifies the manufacturing process of the part 1.

  The attachment between the frame 5 and the lining 7 in a piece of equipment according to the invention is stronger than in the case where an adhesive is used to achieve this fixation.

Claims (10)

  1. Part (1) for equipment for a motor vehicle, of the type comprising: a rigid support frame (5); - a flexible lining (7) covering an outer face (9) of the support frame (5) and comprising at least one attachment projection (31) to the support frame (5); characterized in that the fixing projection (31) is clamped in the support frame (5) following removal of the material from the support frame (5) during cooling.   2. Part (1) according to claim 1, characterized in that the support frame (5) comprises, for each attachment projection (31), a bearing face (45) defining a passage (35) for receiving the fixing projection (31), the bearing face (45) enclosing the fixing projection (31).   3. Part (1) according to claim 2, characterized in that the support frame (5) comprises a body (34) and at least one wall (33) projecting from the body (34), the face of support (45) belonging to the projecting wall (33), the protruding wall (33) being movable, under the effect of the withdrawal, between a position of insertion of the fixing projection (31) and a position of gripping of the fixing projection (31).   4. Part (1) according to claim 3, characterized in that the projecting wall (33) has a length substantially greater than at least 1.5 times the thickness of the body (34).   5. Part (1) according to claim 3 or 4, characterized in that the body (34) has, in a portion adjacent to the projecting wall (33), a recess (49) which opens towards the inner face (40) of the body (41).   6. Part (1) according to any one of claims 2 to 5, characterized in that the passage (35) for receiving the projection converges with an angle between 0 and 60.   7. Part (1) according to any one of the preceding claims, characterized in that the flexible lining (7) comprises a plurality of bearing projections (19) bearing on the outer face (9) of the armature of support (5), the length of the fixing projection (31) being greater than the length of the adjacent bearing projections (19).   8. A method of producing a piece of equipment (1) for a motor vehicle according to any one of claims 1 to 7, characterized in that it comprises the steps of: - heating of the support frame ( 5); - insertion of the fixing projection (31) in the support frame (5); - Cooling the support frame (5) so that it grips, by removal of its material, the attachment projection (31).   9. The method of claim 8, characterized in that the step of heating the support frame (5) has been obtained by molding the support frame (5).   10. Motor vehicle, characterized in that it comprises a piece of equipment according to any one of claims 1 to 7.