EP2525957A1

EP2525957A1 - Assembly of an overmold having hooks and a mold comprising a pedestal

Info

Publication number: EP2525957A1
Application number: EP11704644A
Authority: EP
Inventors: Fabrice Billarant; Marc Woodling
Original assignee: Aplix SA
Current assignee: Aplix SA
Priority date: 2010-01-20
Filing date: 2011-01-12
Publication date: 2012-11-28
Also published as: CA2787355A1; BR112012018052A2; FR2955234A1; CN102802906A; JP5801321B2; US20120291237A1; KR20120128633A; FR2955234B1; JP2013517165A; MX2012008379A; WO2011089334A1

Abstract

The invention relates to an assembly comprising an overmolded element having hooks that is to be overmolded onto a molded object, the overmolded element forming an inner open space defined by two end side walls and a base from which hooks from the element project. Said assembly moreover comprises a mold, the inner walls of which define an inner space of the shape of the object to be formed by molding in the mold, at least one pedestal projecting into the space from said inner wall(s), the overmolded element being, during the flow of the molding foam, in contact with the pedestal. The pedestal comprises a wall-shaped portion having two opposite outer side surfaces, and during the flow of the foam, the respective end side walls of the overmolded element are in contact with the respective opposite outer side surfaces, with no hooks interposed therebetween.

Description

ASSEMBLY OF A HOOK-OVER MOLD AND A MOLD COMPRISING A FOOT

The present invention relates to a molded hook member to be molded to a molded article during the molding of this last, in particular a foam object, in particular a cushion of an ^automotive vehicle. The present invention also relates to an assembly comprising a molded element of this type and a mold comprising a pedestal which cooperates with the overmoulded element during molding. The present invention also relates to a molded object comprising a main body of a molding material, in particular a foam, and a molded element of the kind mentioned above overmolded to the main body. The present invention also relates to an assembly comprising a molded object of this type, in particular a motor vehicle cushion, and a covering, which covers the outer surface of the molded article, the mutual attachment of the molded article, in particular molded cushion, and its covering is effected via a device with hooks and loops, the hooks being derived from the hook element overmolded to the molded object, while loops are derived from the covering. The present invention also relates to a method for manufacturing a molded object of the kind mentioned above.

Today, to fix a covering fabric on the outer surface of a thermoplastic foam molded cushion of a motor vehicle, a hook and loop hook-and-loop fastener system is used. Classically, an overmoulded consisting of a band thermoplastic material has one side of which hooks protrude while, on the other side, it is fixed a metal resin. Then, this overmolded hooks is disposed on a pedestal, formed in particular in the bottom of the mold, a cavity being formed in particular on the upper surface of the pedestal. This cavity ^■ formed at the bottom of the mold on the upper surface of the pedestal comprises vertical walls on which the overmoulded hooks are placed with the hooks disposed on the inside of the cavity during the pouring of the foam to obtain by molding the molded object. At. bottom of this cavity, it is arranged a magnet to attract, through the metal resin, overmolded and hold fixed in contact with the upper edges of the vertical walls with a good seal against the foam. After pouring the foam and let it cool and. to solidify, one obtains the molded object which was overmoulded overmoulded hooks, the hooks then appearing on the outer surface of the molded object and can cooperate with loops (see hooks in the case of a self gripping hooks in hooks) associated with a covering, for example in the form of fabric, for fixing the latter around the molded object by the cooperation of the hooks and loops.

This conventional technique has several disadvantages. In the first place it requires forming, for example by machining, the protection cavity of the hooks at the top of the pedestal. In addition, during the molding process, this technique requires a lot of manpower for the positioning of overmoulded on the pedestal, which hampers large-scale manufacturing. In addition, the magnets placed in the cavity of Protection formed in the pedestal degrades over time due to alternating heating and cooling of the molds. There comes a time during the production process when these magnets have to be replaced and this operation is expensive and time consuming.

The present invention according to a first aspect aims at overcoming the drawbacks of the prior art by proposing a system for overmolding the overmolded element with hooks to the molded object which does not require either the provision of a protective cavity or the use of a magnet, without the protection of the hooks with respect to the foam cast during molding is less good. According to a first aspect of the invention, an assembly comprising on the one hand at least one over-molded hook element intended to be overmolded to a molded object, the overmoulded element forming an open interior space delimited by two end sidewalls and a bottom of which makes or protrudes at least one hook or hooks, derived from the element; and on the other hand a mold whose inner wall (s) define (s) an interior volume of the shape of the object to be formed by molding in the mold, at least one pedestal protruding into the volume from this or these inner wall (s), the overmoulded element being intended during casting of the molding foam to be in contact with the pedestal, the pedestal having a wall-shaped portion having two opposite outer lateral faces, in particular parallel, is characterized in that during the casting of the foam the respective end side walls of the element overmoulded are in contact with the respective opposite outer side faces of the pedestal, without interposed between them hooks, in particular without interposing hooks between them. In fact, according to the invention, the pedestal is gripped by the two lateral walls of the overmoulded element, so that they bear against the two lateral faces, in particular in an elastic manner, to ensure a seal with respect to the liquid foam poured from the interior space at the hooks, without this further that they are deteriorated. In particular, these ^■ are not caught between the two walls of the molded pedestal and which bear one against 1 / other and are not compressed as in the prior art.

Thus, it is ensured good sealing vis-à-vis the foam at the contact between the side faces of the pedestal and the walls of overmolded so that the hooks are well protected. It is no longer necessary to provide on the one hand to form a cavity on the top of the pedestal and secondly a system with magnets and metal materials, or other complex devices to protect the hooks of the liquid foam poured during molding, to ensure the correct positioning of the overmolded element and good protection of the hooks. Thus simplifying the formatting method ^'in place, and in particular positioning of the element molded hook into the mold prior to molding and on the other hand the mold itself is simpler in structure. At the end of the molding, hooks are obtained which appear outside the molded object, at the bottom of a groove or trench which is narrow (especially narrow as the pedestal), and in particular which may be narrower than in the prior art.

According to a preferred embodiment, the hook element encloses, particularly forcibly, by its two side walls, the pedestal.

In particular, the contact between the respective walls of the overmold and the. pedestal is made along a respective line, especially rectilinear. Preferably, the innermost end edges of the two side walls, have a rectilinear shape, preferably being parallel to each other, and the two outer lateral faces of the wall have, seen in plan from above, the same rectilinear shape, so that the respective lines of contact are rectilinear. According to an improvement the contact between the hook element and the pedestal is by clipping.

Preferably, during the casting of. the foam, hooks, and in particular all of the hooks of the overmolded element with hooks, are at a distance from the wall, and in particular from its top. Optionally, they may be flush, that is to say that the top of the hooks touch the top of the wall but without the latter applies pressure on them, especially without it distorts them. Preferably, no hook protrudes from the inner surface of the end side walls, the set of hooks protruding only from the bottom of the hook element. According to a preferred embodiment, each side wall of the hook member has an innermost end edge, the height of the highest point of the hooks being less than the height of the most extreme end edges. towards the inside ; and the pedestal comprises a wall-shaped portion having two outer lateral faces, remote at a distance from each other, which have substantially identical shapes to the shapes of the end edges of the side walls of the overmold, and a thickness of the wall that is to say a distance between the two lateral faces measured in a given direction being just greater than a distance between the two end edges of the two side walls in said given direction. Preferably, both side walls are slightly inclined towards each other, in particular having, viewed in cross section, form a ^"hook, a C shape, a circular arc or the like.

Preferably, the overmoulded element also comprises two front and rear walls, which extend transversely with respect to the side walls and the pedestal has an apex having a shape substantially complementary to the shape of the upper edges of the two front and rear walls, of so that it can come to rest against the two upper edges of the walls, possibly with the interposition of sealing ribs which extend along the two upper edges of the two front and rear walls.

This completely closes the open interior space in which the hooks are located, which are particularly well protected from the foam at the level of the contacts between the two lateral faces of the wall and the two side walls overmolded on the one hand, and at the two front and rear walls and the top of the wall, on the other.

Preferably, the respective upper edges of the two front and rear walls are at respective heights greater than the highest point of the hooks, but lower than the heights of the upper edges of the two side walls.

- According to a preferred embodiment, there is provided a ^'- or more sealing ribs which extend (s) • the edge or along the upper edges of the two front and rear walls.

Preferably, at least a portion of the upper face of the overmolded element with hooks, between the two side walls, in cross section, has substantially the shape of an arc of a circle, especially in the area from which the hooks originate.

According to another embodiment, each innermost upper edge forms a curved line, in particular in an arc of circle and the two lateral faces, seen from above, have shapes identical to these curved lines, said lines respective contact areas being constituted by these curved lines.

Preferably the base plate of the overmolded element extends beyond the two side walls, outwardly, thus forming one or outer edges.

In the final molded object, these two edges will be completely surrounded by the foam, and this anchoring in the foam ensures excellent resistance of the overmold to the molded object. The good anchoring in the foam of the molded object at the end of the molding ensures that the overmolded remains well connected to the molded object when the overmoulded (now anchored and overmolded to the molded object) is unclipped from the pedestal.

This good anchoring of the overmoulded in the foam of the molded object is further favored by the fact that the foam is in contact with the upper surface of the side walls.

Preferably, one or each lateral wall comprises an outer rib, the wall having its greatest thickness at this or these ribs, in particular the two ribs being at the same level and said thickness of the wall being the distance between the two points. more extreme outward of these two ribs.

The present invention also relates to a molded article comprising a main body made of molding material, in particular thermoplastic foam, and at least one overmolded element with hooks of an assembly according to the invention, which is overmolded to the molded main body, the foam being in contact with the overmoulded element, in cross-section around the entire periphery of the overmoulded element, except for the open interior space which extends from an inner upper edge to the other inner upper edge of the two side walls, so that there is formed, above the overmoulded element, a groove opening out of the molded body, the groove having in particular the complementary shape of a wall having a thickness or corresponding thickness at the distance or distances between the two upper inner edges of the two side walls of the pedestal of an assembly according to the invention.

The present invention also relates to an assembly comprising a molded object according to the invention and a covering or cap, in particular a fabric, covering the outer surface of the molded object by conforming to the shape of this outer surface.

The present ^invention also relates to an assembly comprising a molded article and a cover which covers at least partly the outer surface of the molded article, at least one groove or longitudinal trench being formed in the molded article is open towards at the outside, at least one overmoulded element with hooks having hooks being overmolded to the molded object so as to form at least a portion of the bottom of the groove, hooks, preferably the hooks penetrating inside openings loops from the cover to hang and ensure the attachment of the cover to the molded object. According to a second aspect of the invention, independent of the first aspect and forming in itself an invention, there is provided at least two molded hooks which form at least partly the bottom of the trench being arranged one ^'the following the other in the longitudinal direction, the two hook elements being separated from each other by an intermediate zone in which there is no hook element; and means are provided for preventing upward recovery of the trench, particularly at or for each intermediate zone. Thus, hook and loop hook-and-loop fasteners are used for fastening the covering around the object, but in a smaller quantity which has a very favorable effect on the cost, but without, however, detracting from the great simplicity of manufacturing the assembly. and its installation, or the reliability of the attachment, including its tensile strength, the latter being retained or even improved by the means anti remontée.

Preferably, the loops are derived from the outer surface of a gusset attached to the cover and the means for preventing the tent effect are constituted by a ring which extends inside the gusset.

Thus, compared to the prior art in which hook and loop systems are also provided for fastening the cover to the molded object, fewer hooks have been provided, which greatly reduces the costs, and provision has been made for replacing the hard rush, especially thermoplastic material, much less ^costly but which provides a tensile strength up as good or better. In addition, in the case of a trench that does not extend linearly, but having curved portions, can still use the ^elements' rectilinear molded, their adaptation to the curved extension is facilitated by the fact that they may be spaced from each other and need not be continuously disposed over the entire extension of the trench, which otherwise should have a corresponding curved shape.

Preferably, the loops are derived from the outer surface of a gusset fixed to the covering and the means for preventing the tent effect consist of a ring which extends inside the gusset. Preferably, the loops come from the lower part of the periphery of the gusset, in particular only from this part.

According to an improvement, the length of the intermediate zone, that is to say the distance between two successive adjacent overmolded elements in the longitudinal direction is such that, without the ring, there appears a rising effect; and the material and the dimensions of the rod are such that it is sufficiently rigid so that there is a lesser effect of ascent when it is received in the gusset, and in particular so that there is no longer any.

By thus providing a rigid rod, especially rigid ^' in the vertical plane, no longer tent effect and the cost of material to form overmolded elements is less, those ci' extending on a smaller proportion of extension in length of the trench. Moreover, the insertion of the loop element in the trench is facilitated, the rod having a function of support and guidance for this insertion. Furthermore, in the case of a trench that does not extend straight, but with curved parts, it is possible to use rectilinear overmoulded elements, their adaptation to the curved extension being facilitated by the fact that they can spaced apart from one another and do not need to be continuously arranged over the entire extension of the trench, which otherwise should have a corresponding curved shape.

According to a preferred embodiment, each hook element has in cross section the shape of a U or a C whose two branches are directed towards the outside of the groove, the inner surface of the U or C having two distal end sections or upper of which no hook protrudes and an intermediate bottom section which the hooks of the hook element protrude.

According to an advantageous embodiment, the groove has two lateral faces formed by the molding material of the molded object which extend from the outside to the respective upper or distal edges of the legs of the U of each hook element and the respective inner surfaces of the two branches of the U or C are in flush with the respective lateral faces.

In particular, the lateral faces of the groove are vertical and come to the right of the edges. upper interior of the respective branches of the U or C.

According to a preferred embodiment, the groove comprises at least one section of curved shape in which extends at least one overmolded element, rectilinear or curved shape, the length of the overmoulded element being less than that of the curved section.

Preferably, the width of the groove is defined as the smallest distance between two of its walls facing each other, and in particular when the hook elements are aligned in a given direction, the width of the trench is measured perpendicularly to this given direction. , and the width dimension of the loop element out of the loops, ie the sum of the width dimension of the rod and twice the thickness of the gusset (excluding the loops), is substantially equal to the width of the trench being, however, just below this width of the trench. Preferably, the distance between the most respective points inside the upper edges of the two branches of the U or C of each overmold is substantially equal to the width dimension outside the loops of the loop element, it is to say the sum of the width dimension of the rod and twice the thickness of the gusset (excluding the loops), however being just greater than this dimension in width.

Preferably, the gusset is fixed to the covering, in particular by being sewn, at the level of the superposition of two edges of two pieces or sheets of the covering.

Preferably, the distance over which the intermediate zone extends between the at least two overmoulded hook elements is greater than 50% of the largest dimension, in particular the length dimension, of each overmoulded element, preferably is greater than the largest dimension in length of each overmoulded.

Preferably, the distance between the at least two overmolded is greater than 20mm, especially greater than 100 mm, in particular is between 100mm and 500 mm.

Preferably, the rod has a cross section of oval shape, in particular with its major axis oriented in the direction from the bottom of the trench to the outside, ie substantially perpendicular to the base of each overmoulded.

Following a mode of. embodiment particularly preferred, the rod has a square or rectangular cross section whose corners are rounded, and in particular the length, in the case of a rectangular shape, is oriented in the direction from the bottom of the trench to the outside.

By thus providing a rigid rod, there is no more tent effect and the cost of material to form the overmolded elements is less, those ci 'extending on a smaller proportion of the extension length of the trench. Moreover, the insertion of the loop element in the trench is facilitated, the rod having a function of support and guidance for this insertion. In addition, in the case of a trench that does not extend linearly, but having 'curved portions, they may still use ^elements ^■ rectilinear molded, their adaptation to the curved extension is facilitated by the fact that they may be spaced from each other and need not be continuously disposed over the entire extension of the trench, which otherwise should have a corresponding curved shape.

According to one embodiment, the trench comprises at least one section of curved shape in which extends at least one overmolded element of rectilinear shape, the length of the overmoulded element being less than that of the curved section.

Preferably, the shape of the gusset when the rod is inserted therein is at least partly complementary to the shape of the cross section of the zone of the upper face of the hook elements from which the hooks originate, in particular the rod is of section while the said zone has a section in the shape of an arc of a circle. Preferably, the gusset is fixed to the covering, notoriently being sewn, at the level of the superimposition of two edges of two pieces or sheets of the covering. Preferably, the width of the trench or groove is defined as the smallest distance between two of its walls facing each other, and in particular when the hook elements are aligned in a given direction, the width of the trench is measured perpendicular thereto. given direction, and the width dimension of the loop element, ie the sum of the width dimension of the ring. and twice the thickness of the gusset, is substantially equal to the width of the trench, in particular just smaller than the width. The present invention also relates to a method of manufacturing a molded object, in particular ^'of a set according to the second aspect of the invention.

The manufacturing method of the invention by molding a molded object, in particular a molded object of an assembly according to the second aspect of the invention, comprising the steps of taking a mold having the shape of the object that is to be molded, a wall-shaped pedestal projecting from a wall of the mold defining the volume of the mold; is characterized by the step of enclosing the pedestal by an overmoulded element having two walls at a distance from each other so that the two side walls of the hook element come to bear against two faces of the pedestal along at least two respective contact lines, so as to seal the interior space between the two walls of the overmoulded and pour the foam to mold the object. The present invention also relates to a third aspect, independent of the first and second aspects and forming an invention itself, to a molded overmold element. It may, however, be intended to form part of an assembly according to the first aspect of the invention and / or a molded object of an assembly according to the second aspect of the invention.

According to the third aspect of the invention, the overmoulded hook member having two side walls which are spaced from each other and a bottom so as to form an open inner space having a larger width measured in a direction extending from one wall to the other, in particular perpendicular to the two walls, and at least one hook, preferably a plurality of hooks, coming from the bottom, is characterized in that the upper or distal portions of the two side walls are inclined towards each other, so that the distance between the two most interior of the upper edges of both walls is smaller than said greater width.

Preferably, the bottom, in section transversely to the walls, consists of a central rectilinear section terminated on each side by a respective right and left section having substantially the shape of an arc of a circle, especially in the zone from which the hooks.

Preferably, the hooks of the overmolded element protrude only from the bottom of the interior space.

An embodiment of the invention will now be described by way of example with reference to the drawings in which: Figure 1 is a perspective view from above of a molded element with hooks according to the invention; Figure 2 is a sectional view along the line

AA of Figure 1; Figures 3A, 3B and 3C are sectional views of a portion of respective molded articles according to the invention having the overmoulded element of Figures 1 and 2; Figures 4A and 4B are side views of the overmoulded hook member of Figures 1 and 2 and a respective wall-shaped pedestal on which is positioned the overmolded hook member; Figures 5A and 5B are views similar to Figures 4A and 4B, but showing the state in which the respective wall-shaped pedestal is force-inserted (clip-like) so as to seal-protect the interior space for receiving the hooks inside the overmoulded element with hooks, the assembly of FIG. 5A corresponding to the molded object of FIG. 3A and that of FIG. 5B to the molded object of FIG. Figure 3B; FIG. 6 is a cross-sectional view of a loop element according to the invention, resulting from a covering intended for cover the molded object of Figure 3; Figures 7 and 8 schematically show the cooperation of the loop element and the hook element at the bottom of the trench of the molded object of Figure 3 when covered by a covering comprising the element. loops of Figure 6, in the case (Figure 8) where the rigid plastic rod is inside the gusset and in the case (Figure 7) where it is not; FIG. 9 schematically represents another embodiment of a hook-overmoulded element in a cross-sectional view identical to that of FIG. 2; Figure 10 shows another possible embodiment of a pedestal of an assembly according to the invention in a view identical to Figures 4 or 5; Figure 11 is a sectional view in a trench of the molded object of an assembly according to the invention; Figure 12 is a view identical to Figure 11 of another embodiment of an assembly according to the invention; Figure 13 is a schematic sectional view of an embodiment of a covering of a molded object according to the invention; Figure 14 is a schematic sectional view of another embodiment of a cover of a molded object according to the invention; Figure ^"15 is a view of a molded article, the top of a trench which in this embodiment has curved sections and straight sections, Figure 16 shows yet another possible embodiment of a pedestal of an assembly according to the invention in a view identical to FIGS. 4 or 5, and FIG. 17 is a view in section identical to that of FIG. 2 of another embodiment of a molded-over element with hooks comprising a bottom plate from which the hooks come.

To ^'Figures, and in particular to Figure 1, there is shown in a perspective view a molded hook member according to the third aspect of the present invention and which can be implemented in the first and / or second aspects of the present invention. The element 1 is intended to be arranged in a mold to mold a molded object, the object to be molded being a molding material, in particular a foam, in particular a thermoplastic foam. When the foam is poured into the mold, it will come in a liquid manner in contact with the overmoulded element, then, by freezing, will make the attachment to the overmoulded element. The objective is that, when pouring the foam in the mold, the hooks are protected so that the foam does not come pollute them by inserting under the hooks, because once the foam under the hooks, they become unusable and can: no longer cooperate with loops to achieve their function of hooking and fixing hooks in loops.

The overmolded element 1 comprises a plate 2 of a rectangular base having a large length L and a width 1. ^The a length L extends in the longitudinal direction of the molded element 1 while the width extends in the direction cross. On the upper side of the plate 2 extend two side walls 3 and 4. Each of these side walls 3 and 4 has an upper edge, here constituted by a substantially horizontal surface in the figure, and each upper edge comprises a line 5 and 6 constituted by the points of the innermost upper edge, it is to say on the side of the other wall. In cross-section, particularly as shown in FIG. 2, these lines 5 and 6 form a point which is the innermost inside. These two lines 5 and 6 are here rectilinear. According to another embodiment, shown in FIG. 9, these upper edges are not necessarily a flat surface and may be in echelon. Thus, in FIG. 9, the upper edge has a first horizontal face (corresponding to the upper surface of the wall 3 outside the rib) followed by a second horizontal face (the upper surface of the rib) in a step relative to the first face and terminated by a curved portion extending from the point of the second innermost horizontal face to the innermost point of the curved portion which corresponds to the innermost point of the edge upper walls 3 and 4. Thus, in cross-section, in particular along the section Α-Ά of FIG. 1 shown in FIG. 2, the overmold has substantially the shape of a U or a C whose branches are constituted by the two walls 3 and 4. The inner surface of ϋ consists of three sections, namely two end sections which each extend from point 5, respectively 6, the most

^• the interior to an intermediate section of bottom which is delimited by the hooks 38 more lateral on either side. So, in both sections

^• end, there are no protruding hooks and

^• The set of overmoulded hooks protrude from the intermediate intermediate section.

In order to precisely delimit the bottom of an overmoulded element of the present invention, a first method of definition thus consists in considering the hooks and defining the bottom as the smallest surface delimiting the interior space in which all the hooks . A second method consists, in each cross section, in projecting vertically (that is to say perpendicularly to the plane of the base plate in FIG. 2 for example) the two innermost points (5 and 6) on the inner surface delimiting the interior space to obtain the two projected points 5 'and 6'^' between which it will be considered that the bottom extends.

To define the bottom of an overmoulded element according to the invention, one or other of the two methods can be used. In Figures 1 and 2, the distal end portions of the side walls 3 and 4 are slightly inclined towards each other. Thus, in cross-section, for example at the level of the section AA, the overmoulded element 1 defines an open interior space delimited by the two walls 5 and 6 and by the upper face of the plate 2. This interior space has, as shown, preferably, a floor 7 forming the bottom of the open inner space defined by the overmoulded, here C-shaped. From this floor or bottom 7, project all the hooks 38, while no hook protrudes from the inner surfaces of the two walls 3 and 4 end. These hooks 38 can be arranged as desired, they are preferably, as shown, arranged in rows and columns, in particular as shown having their head which, in a given column, is oriented alternately to the left and to the right in the figure.

The largest distance OD, measured in the direction perpendicular to the walls, ie the horizontal direction in Figure 2, is the distance between the two walls at the height h. It is greater than the distance dO between the two end edges. The same relationship holds in the embodiment of Figure 9. In Figure 2, the embodiment is such that the cross section is the same ^'for all the cross sections along the longitudinal direction between the two front walls and back 8 and 9, because the walls and the edges are here rectilinear. However, it is possible to envisage an embodiment in which this cross section will vary, for example when the walls and the edges have a certain curvature seen in a top plane, for example in an arc of circle or oval, or any other form imaginable. In this case, the relationship OD greater than dO is valid in each cross section.

The overmold also has two walls 8 and 9 front and rear. The walls 8 and 9 and front and rear side walls 3 and 4 and 7 base floor define the inner space open in ^'which the hooks are located. Each front and rear wall 8 and 9 has an upper edge 10 and 11 respectively, which extends from one side edge 5 to the other opposite side edge 6. These edges 10 and 11 here have the shape of a C. Along the upper edges 10 and 11 of the walls 8 and 9 front and rear, extend seals 13.

Viewed from above, the upper inner edges of the walls 8 and 9 are straight lines. These lines may not be straight and have any shape, including having one or curved parts.

The element 1 described above is intended to be deposited in a mold, into which liquid foam will be poured, which in hardening will attach to the side walls 5 and 6 as well as to the lower surface of the plate 2 and the outer faces of the front and rear walls 8 and 9 to thereby secure the hooks to the molded foam object. In the mold, at least one pedestal 12 in the form of a wall projects from the inner wall 16 of the mold which defines the volume having the shape of the object which it is desired to manufacture by molding. One or more pedestals can be provided depending on the number of trenches that one wishes to form in the final molded object to have the hooks therein. In particular one can foresee a networks of pedestals that will form a network of trenches, and some of them may be curved. In order to prevent the foam from being poured onto the hooks or coming into contact with them, it is advisable, after the pouring of the foam, to protect the hooks from contact with the poured foam. To do this, it is clipped or held by force or the elements overmolded hooks on the pedestal or pedestals, hooks turned towards the pedestal. On a given pedestal, it is possible to have a single overmoulded element or a plurality of them, one after the other, and in the latter case, they can be placed at a distance from one another, as in the of the second aspect of the invention, but also very close to each other, or even end to end if desired.

The wall 12 has two opposite side faces 30 and 31. Seen from above, that is to say seen according to the arrow F of Figures 4 and 5, these faces have the shape of a straight line. They thus have the same shape as the inner upper edges 5 and 6 of the two side walls 3 and 4.

The distance D between the two faces 30 and 31, measured in the direction (horizontal in the figure) perpendicular to the two faces 30 and 31, which corresponds to the thickness of the wall, is substantially equal, while being slightly greater, to the distance d0, measured in the same direction between the two upper edges 5 and 6 of the side walls 3 and 4.

In the case where the wall does not have a constant thickness along its extension in the longitudinal direction (perpendicular to the plane of FIGS. 4 or 5), the thickness D measured in each cross section will be substantially equal, while being slightly greater, to the distance dO between the two innermost end edges 5 and 6 at the level (along the longitudinal direction) where the measurement is made, the shapes of the faces of the wall being complementary to those of the end edges. Thus one could for example provide an arcuate shape rather than rectilinear for these edges 5 and 6 and for the faces 30 and 31, the important thing being that the faces and edges have substantially the same shape to ensure a seal screw to the foam when the wallet is inserted between the side walls.

As shown in FIGS. 5A and 5B, when the overmolded element 1 is in contact with the faces 30 and 31 of the pedestal 12 during molding, this contact takes place along at least the straight lines defined by the edges 5 and 6 of FIG. end. In the embodiment shown, this contact takes place on planes encompassing these lines. In addition, the wall 12 has a crown portion whose shape is complementary to the shape of the upper edges 10 and 11 of the walls 8 and 9 front and rear. Thus, here the top of the wall 12 has a C-shaped or arcuate shape corresponding to the C-shaped or arcuate upper edges of the walls 8 and 9 front and rear. Coming to squeeze the element 1 so that its two side walls come to grip the pedestal 12 between their two edges 5 and 6, these two edges are slightly spaced from one another to allow the passage of the wall within it until its top 15 comes into contact with the two upper edges 10 and 11 of the side walls 8 and 9. The elasticity of the two end edges makes that they ensure the seal at the contact with the corresponding faces of the wall, the two walls tending to return towards each other by elasticity, while the sealing ribs 13, which are between the top of the wall 12 and the upper edges of the walls 8 and 9, provide excellent étanc éité hooks when the foam is poured.

According to an improvement shown in Figure 10, one can provide two ribs which project laterally from the two side faces 30 and 31 of the wall. The largest width of the wall in a given cross section is the distance D between the two most lateral points of the two ribs, and this distance D is greater than the distance dO. According to another embodiment shown in FIG. 16, two longitudinal grooves can be provided in the two opposite lateral faces 30 and 31 intended to receive the end lateral edges by snapping. The two embodiments described above are improvements involving clipping or snapping. However, they are not necessary as such to obtain the effect of the invention the latter being obtained as soon as a pedestal is introduced between the two side walls with a mutual contact maintained, for example by the fact that the two walls that have been spread outward tend to return inwards by bearing against the wall.

Once the pouring of the foam is completed and the foam hardened, the molded object is removed from the mold. It is formed, on the outer surface of the molded object, a trench 15 longitudinal (the direction in length being perpendicular to Figures 3) having a shape substantially complementary to that of the wall 12. The foam extends around the molded element 1 except the inner faces below the end edges and from the bottom of the open interior space. In particular, the foam extends to cover the upper surfaces of the two side walls 3 and 4 to the points 5 and 6 the most inside the upper edges of the two walls. Foam defines two vertical faces 50 and 51 of the trench, vertical faces which extend from the upper opening of ^'the trench that opens to the exterior of the molded object to the respective upper edges of the walls 3 and 4 forming the branches of the U of overmoulded. The sections ·. end without hooks of the inner surface of the overmold are substantially parallel and in continuity with the vertical faces 50 and 51. The passage of the vertical faces 50 and 51 to the respective inner portions is smooth, without asperity, especially at the junction .

3A, 3B and 3C show a portion of respective molded articles thus obtained. Of course, it is possible according to the molded object several trenches of this kind each comprising at least one hook element according to the invention. In particular, one can provide a very long pedestal, which encloses several elements overmolded at a distance from each other to thereby obtain a trench having at its bottom several overmolded at a distance from each other.

Once the molding of the object in -mousse comprising one or more overmolded hooks completed and, in particular when the molded object is a car cushion, it is necessary to cover it with a cover or a cap. This covering is linked to loop elements, which will come to cooperate with the hooks to fix the covering to the molded object by covering it in particular by marrying the shape of its outer surface.

In Figure 6, there is shown a loop element of this kind. It comprises a gusset ^'20 consists of a textile sheet material folded on itself, of the loops being from the -extérieure surface of the gusset. These loops 21 can in particular have been woven or knitted to the outer surface ^'of the pocket 20. Two pieces in the form of sheets 22 and 23 forming the covering are superposed ^at' their edge and the gusset is sewn to the side (see Figures 13 and 14) of the two edges to thereby bring together the two sheets 22 and 23 to form the covering. Thus, it will insert the gusset 20, which is at the junction between the two sheets 22 and 23, at the bottom of the trench 15 so that the loops come into contact with the hooks to thereby secure the cover around the molded object, particularly along the contours and walls of the trench 15.

In Figures 7 and 8, there is shown a side view (the molded object has been omitted) of the connection between the hooks and loops. At the bottom of the trench, were ^■ prepared, by way of illustration, two elements 1 molded hooks. Of course, the trench could extend in length over a greater distance so as to provide more than two hook elements.

In the gusset 20 of the loop element, it has been further inserted a rod 24 which here consists of a Rigid plastic rod of circular cylindrical shape, whose function is to stiffen the assembly. The rigid plastic rod is, for example, polypropylene (PP) or polyethylene (PE) and has a diameter of at least 2 mm. However, one could also provide a hollow rod, that is to say in the form of a tube. When the rigid rod 24 · is not present inside the gusset 20, there is obtained, in the intermediate zone between the two elements 1 to hooks, a tent effect in that the gusset 20 tends to rise, that is to say, to bend, so ^" to deform in the manner of a tent, as shown in Figure 7.

On the other hand, when one. disposed within the element 20 the rigid rod 24, the tent effect disappears, as shown in Figure 8. Thus, the two elements 1 shown in Figure 7 are at a distance one of the other such that, when there is no rod 24, there is a tent effect and when there is a rod 24 which is disposed inside the gusset 20, there is has more tent effect. In particular, this distance may correspond to a distance greater than 20 to 25 mm, knowing that one can easily reach 80 mm, or even 150 to 200 mm.

As shown in Figure 4A, a thickness D of the wall 12 is preferably between 8 and 16 mm and even more preferably between 9 and ^'12 mm. These thickness dimension ranges are however also valid for the other embodiments shown in the drawings. In the embodiment corresponding to FIGS. 3B, 4B and 5B, the pedestal tapers downwards (that is to say in the direction of the arrow F). This results in a trench in Figure 3B whose width tapers towards the upper opening. As in the embodiment of FIG. 3A, however, the innermost points 5 and 6 of the upper edges of the two walls do not protrude from the two faces 50 and 51 of the groove 50. It is the same in the embodiment of Figure 3C. ^■

In FIG. 11, the assembly of FIG. 8 is seen in cross-section with the trench 15. The width of the trench is measured horizontally in the figure. The sum of the diameter of the rod and twice the thickness of the folded sheet on itself to form the gusset is substantially equal to the width of the trench. In particular there ^'is mismatch between the gusset plate and each wall of the trench.

In Figure 12, we see another embodiment in which the ring is. oval or elliptical section having its major axis oriented in the vertical direction in the figure, that is to say the bottom of the trench to the outside. The total width of the loop element (dimension of the minor axis and twice the thickness of the gusset) is substantially equal to the width dimension of the trench.

In the present application, the mutual attachment of the molded article to the covering has been described by a cooperation of hooks coming from the molded object and loops of the covering. It should be noted that hooks which cooperate with the hooks of the overmoldings in the manner of a self-gripping hook with hooks in hooks could also be provided instead of loops, and this is why in the claims it is necessary to understand the term loop in a broader sense that also includes the fact that it may be hooks.

In Figure 15, there is shown an embodiment of a molded object having a non-rectilinear extension trench and in particular having curved sections. As the overmolded elements do not need to be arranged continuously, and in particular end to end in the trench, the assembly is simplified and in particular it is not necessary to provide overmoulded elements of curved shape complementary to the shape. of the curved section of the trench, the same elements of small length and at a great distance from each other used in the sections. rectilinear also suitable in curved sections of low curvature. In the present application, hook means any element having an ability to hang on, including a loop. In particular, a hook is an element comprising a rod and a head projecting laterally from this rod. Thus, a mushroom-shaped element, harpoon, double head and the like is within the meaning of the invention a hook.

In the context of the first and third aspects of the invention, the mutual attachment of the molded object to the covering has been described by a cooperation of hooks coming from the molded object and loops of the covering. It should be noted that loops could also be provided instead of hooks which would cooperate with the hooks of the overmoldings in the manner of a self-gripping hook in hooks and that is why in the context of these two first and third aspect of the invention, it is necessary to understand the term loop in a broader sense which also encompasses the fact that it may be of hooks. On the other hand, in the context of the second aspect, the term loop implies the existence of an opening through which can pass a hooking element and hang on. Similarly, in the context of the first aspect, it can be used with a single overmoulded element or with several of them on a given pedestal, and in the latter case can be provided to have them at a distance (it is then also in the context of the first aspect of the invention) of each other or on the contrary very close to each other, or even end to end if desired.

Claims

REVENDICA IONS

1. An assembly comprising on the one hand a molded element with hooks, intended to be overmolded to a molded object, the overmoulded element forming an open interior space delimited by two end side walls and a bottom of which makes or protrudes at least a hook or hooks coming from the element; and on the other hand a mold whose inner wall (s) define (s) an internal volume of the shape of the object intended to be molded in the mold, at least one pedestal projecting into the volume to from this or these inner walls (s), the overmoulded hook element being in contact with the pedestal during the casting of the molding foam, the pedestal comprising a wall-shaped part having two opposite outer lateral faces, in particular parallel, characterized in that during the casting of the foam the respective end side walls of the overmoulded element are in contact with the respective opposite outer side faces, without interposition of hooks between them.

2. An assembly according to claim 1, characterized in that the overmoulded element hooks forcibly grips by its two side walls the pedestal.

3. Assembly according to claim 1 or 2, characterized in that the contact for each wall is made according to at least one respective line, in particular rectilinear.

4. An assembly according to claim 1, 2 or 3, characterized in that the contact between the hook element and the pedestal is by clipping.

5. ^Assemblage according ^'to one of Claims 1 to 4, characterized in that during casting the foam, hooks, including all hooks are remote from the wall.

6.Assembly according to one of claims 1 to 5, characterized in that no hooks protrudes from the inner surface of the end side walls.

Assembly according to one of Claims 1 to 6, characterized in that each side wall of the hook element has an innermost end edge, the height of the highest point of the hooks being lower than at the height of the innermost end edges; and the pedestal comprises a wall-shaped portion having two opposite outermost outer side faces which have substantially identical shapes to the shapes of the end edges of the overmolded side walls, and a thickness of the wall, that is to say a distance between the two lateral faces measured in a given direction being just greater than a distance between the two end edges of the two side walls in said given direction.

8. Assembly according to one of claims 1 to 7, characterized in that the two side walls are slightly inclined towards each other, particularly in having, in cross-section, a C-shaped, arcuate shape, or the like.

9. Assembly according to one of claims 1 to 8, characterized in that the overmoulded element also comprises two front and rear walls, which extend transversely relative to the side walls and the pedestal has a ^" vertex having a shape substantially complementary to the shape of the upper edges of the two front and rear walls, so that it rests against the two upper edges of the walls, possibly with the interposition of sealing ribs which extend along the two upper edges of the two walls front and rear .

10. Assembly according to one of claims 1 to 9, characterized in that the overmolded element extends outside the two side walls, to thereby form one or outer edges.

11. Assembly according to one of the preceding claims, characterized in that to define it defines the bottom as being the smallest surface defining the interior space in which are all the hooks.

12. Assembly according to one of the preceding claims, characterized in that in each cross section, projects the two points (5 and 6) the innermost on the inner surface delimiting the interior space to obtain the two points projected 5 'and 6' between which it will be considered that the bottom extends.

A molded article comprising a molding main body, in particular of thermoplastic foam, and an overmoulded element with hooks of an assembly according to one of the preceding claims, which is overmoulded to the molded main body, the foam being in contact with the mold. overmoulded element, in cross section around the entire periphery of the overmoulded element, except only a region corresponding to the interior space, so that it is formed above the overmoulded element, a groove or trench opening out of the molded body, the trench having in particular the complementary shape of a wall having a thickness or thickness corresponding to the distance or distances between the two upper inner edges of the two side walls of the pedestal.

13. A method of manufacturing by molding a molded object, in particular a molded object according to claim 12, comprising the steps of taking a mold having the shape of the object that is to be molded, a pedestal made of wall form projecting from a wall of the mold defining the volume of the mold; and characterized by the step of enclosing by an overmoulded element having two walls spaced apart from each other the pedestal so that the two side walls of the hook element come to bear against two faces of the pedestal along at least two respective contact lines, so as to seal the interior space between the two walls of the overmoulded and pour the foam to mold the object.