FR3038248A1 - METHOD AND DEVICE FOR MANUFACTURING A HYBRID OR COMPOSITE PART BASED ON THERMOPLASTIC MATERIAL HAVING A FACE OF APPEARANCE AND A TECHNICAL FACE - Google Patents

Abstract

The present invention relates to a method and device for manufacturing a hybrid part. A method characterized in that it consists in providing a mold device (6) with, on the one hand, a matrix (8 ') comprising moving parts (9) and, on the other hand, a punch provided with a recess ( s) (10), the moving parts (9) being intended to participate in the definition of the configuration of the impression (9 '), in a first position, and to delimit with the recesses (10) injection cavities for said technical components, in a second position, and in that it consists, during a first cycle phase, in injecting the technical components and, during a second cycle phase, in using the mold device (6) as a mold compression forming to assemble the different layers (4, 3 ') and to conform the composite part.

Description

DESCRIPTION

The present invention relates to the field of surface-shaped parts based on thermoplastic material and natural fibers, intended in particular for applications of the interior trim type of motor vehicles (dashboard, ceiling tile, door interior lining, etc.). ).

These hybrid or composite parts commonly have an apparent appearance face, for which the aesthetic appearance is essential, and a rear technical face, for which the accuracy and speed of realization, stiffness, low cost and / or the possibility of complex configurations are essential parameters.

They generally comprise, essentially, on the one hand, a base body or substrate obtained by thermocompression of a sheet based on thermoplastic material and natural fibers, on the other hand, a decorative sheet, attached to the base body and defining the visible face and, finally, components and / or technical elements reported on the rear face of the basic body,

Said components and / or technical elements may for example consist of fixing sites, attachment, indexing or wedging of the part on the frame, the door or the like, reception sites or accommodation accessories or technical or aesthetic equipment, structures for reinforcing or stiffening, locally or otherwise, the substrate or similar interfaces (ribs, fins, ...). These components and / or elements may be in the form of separate pieces that are independent of each other, partially grouped together locally or else constitute an integral structure grouping them all together and forming, if necessary, a layer in their own right.

The present invention more particularly relates to a method and a mold device for the manufacture of a part of the type mentioned above, and a resulting part obtained by this method.

Currently, there are mainly two known methods for obtaining a hybrid or composite surface part referred to above, each of them having major limitations.

Thus, a first known technology allows to perform in one operation hybrid parts based on natural fibers impregnated with thermoplastic material by thermocompression, and injection molding for the realization of the technical side, these two operations being performed in the same tool. Nevertheless, since it is not possible to add the decoration during the compression phase, given the problems of marking the surface of appearance during overmoulding of the technical part (for most decorative coatings used), is necessary, in a second consecutive operation, implementing a second tool, to report the decoration by sheathing, thermogainage or a similar process.

Another known technology allows to realize in one operation and with a single tooling forming a fibrous mat of natural fibers impregnated with thermoplastic material with a decoration of polyvinyl chloride, polypropylene, textile or other.

However, because of the injection pressure necessary for their production, it is not possible to inject the components and / or elements of the technical face without marking the decor sheet. In this case, it has therefore been envisaged to manufacture said components and / or technical elements separately, in a specific injection mold, and then in a second operation, or to fix them by gluing, welding or other on the back face of the substrate shaped with the decor, or to position them in the thermocompression mold before compression of the substrate with the decor.

Therefore, the two aforementioned known technologies both require at least two distinct and successive operations or production cycles, and two different tools or operational positions.

The present invention is intended in particular to overcome the aforementioned limitations. For this purpose, it relates to a method of manufacturing a hybrid or composite part of the type mentioned in the introduction to the present, said method of providing a mold device with a first part comprising a punch and a second part comprising a matrix, the first and second parts being relatively movable relative to each other to define at least open and closed states of the mold device, the shapes and topographies of the matrix and punch respectively determining, on the one hand, the shape and surface condition of the appearance side and, on the other hand, the shape and configuration of the components and / or elements of the technical face, as well as by mutual cooperation the general shape of the component, characterized in that it consists in providing a mold device with, on the one hand, a matrix comprising at least one part of an internal surface imprint or topography which is bile and, on the other hand, a punch provided with one or more recess (s) or hollow whose shapes and positions correspond to those of the components and / or technical elements to be injected from the part, the part or parts ( s) mobile (s) being fit (s) and intended (s) to participate in the definition of the configuration of the imprint determining the shape and surface condition of the aspect face, in a first position, and closing off said recess (es) or recess (s) to delimit one or more injection cavities for said components and / or technical elements, in a second position, and in that it consists, during a first cycle phase, using the mold device as an injection mold, for injecting the components and / or technical elements, while the mobile part (s) are in their second position, and, during a second cycle phase, to use the mold device as a compression forming mold, for nform the decor sheet and the sheet of thermoplastic material and natural fibers, after preheating thereof, and to assemble the components and / or technical elements produced during the first cycle phase with this preheated sheet, while the or moving parts are in their first position. The invention also relates to a mold device for manufacturing by carrying out the aforementioned method of a hybrid part of the type referred to in the introduction, as well as a resulting part. The invention will be better understood, thanks to the following description, which refers to preferred embodiments, given by way of non-limiting examples, and explained with reference to the appended diagrammatic drawings, in which: FIG. a simplified schematic view in side elevation of an installation with a mold device according to a first embodiment of the invention as well as its accessory equipment and sheets of starting materials; FIGS. 2A to 2H schematically illustrate the various operating steps of the two phases of a hybrid part manufacturing cycle according to the invention, with a mold device as represented in FIG. 1, and FIG. view illustrating the implementation of the operations of Figures 2C and 2D with an alternative embodiment of the mold device according to the invention.

Figures 2A to 2H illustrate the successive operations of a manufacturing cycle of a hybrid part 1 with an apparent face 2 and a technical face 2 '.

Such a part 1 essentially comprises, firstly, a base body or substrate 3 obtained by thermocompression of a sheet 3 'based on thermoplastic material and natural fibers, on the other hand, a decor sheet 4, reported on the basic body 3.

The method implemented consists in providing a mold device 6 with a first part 7 comprising a punch 7 'and a second part 8 comprising a matrix 8', the first and second parts 7 and 8 being able to be moved relative to one another by relative to the other to define at least open and closed states of the mold device 6, the shapes and topographies of the die 8 'and the punch 7' respectively determining, on the one hand, the shape and the state of surface of the face of appearance 2 and, secondly, the shape and configuration of the components and / or elements 5 of the technical face 2 ', as well as by mutual cooperation the general shape of the part 1.

According to the invention, the method consists in providing a mold device 6 with, on the one hand, a matrix 8 'comprising at least one part 9 of impression or internal surface topography which is mobile and, on the other hand, on the other hand, a punch provided with one or more recess (s) or recess 10 whose shapes and positions correspond to those of the components and / or technical elements 5 to be injected from the workpiece 1, the movable part (s) (s) 9 being fit (s) and intended (s) to participate in the definition of the configuration of the footprint 9 'determining the shape and surface condition of the aspect face 2, in a first position, and closing off said recess (es) or recess (10) to delimit one or more injection cavities (10 ') for said components and / or technical elements (5) in a second position .

It also consists, during a first cycle phase, in using the mold device 6 as an injection mold, for injecting the components and / or technical elements 5, whereas the mobile part (s) 9 are in their second position, and, during a second cycle phase, using the mold device 6 as a compression forming mold, to conform the decor sheet 4 and the sheet 3 'based on thermoplastic material and natural fibers, after preheating the latter, and to assemble the components and / or technical elements 5 produced during the first cycle phase with this preheated sheet 3 ', while the moving part (s) 9 are in their first position.

Thanks to the invention, the piece 1 is made, as a finished part, in a single production cycle using a single mold device 6 with two constituent parts 7 and 8. In addition, by the particular operating mode of the invention, any risk of marking the aspect face 2 or the decor sheet 4 related to the injection is discarded. In addition, the rate of production is optimized due to the absence of manipulation and intermediate transfer of part blanks.

Finally, the production cycle can be fully automated, avoiding operator intervention near the device 6 in current operation. In particular, the transformation of the injection mold mold device 6 into a thermoforming mold and vice versa is effected by simply moving parts 9 forming shutters and conformers.

According to a first important characteristic of the invention, the displacement of the mobile impression portion (s) 9 of the matrix 8 'between its or their first and second positions consists of a translation movement. linearly of said portion or portions 9 relative to the remainder of the die 8 ', between a retracted position and an extended position.

As can be seen by comparing FIGS. 2A and 2H, on the one hand, with FIGS. 2B and 2G, on the other hand, it is advantageously provided that in its or their first position, the impression part (s) mobile (s) 9 of the matrix 8 'would be flush (s) and contiguous (s) with the surrounding area (s) of the inner surface of the rest of the footprint (s), and that in its or their second position, the movable part (s) 9 would be protruding relative to said surrounding area (s). The outcropping of the moving parts 9 and the surface continuity between the latter and the surrounding impression surface areas 9 'are such that no discontinuity or mark is produced on the apparent face 2 of the part 1 when the thermocompression phase.

In accordance with a preferred embodiment of the invention, provision may be made to provide a die 8 'provided with movable fingerprint portion (s) 9 mounted with guided sliding capability in housings 9 corresponding to the body of the die 8 'and to effect the displacement of the said movable part (s) 9 via an actuator (s) of electric, hydraulic or pneumatic type, controlled individually or in a grouped way.

Advantageously, the actuators are in the form of double-acting hydraulic cylinders, mounted in the housings 9 "at the rear of the moving finger portions 9 or in a technical compartment 15 associated with the die 8 ', their control rods then extending into said housings 9 "by being connected to the sliding parts or wedges 9, for example in the form of a hollow body.

In the retracted position (or first position), the shims 9 may possibly be supported on stops provided in the recesses 9 ", thus enabling the pressure forces exerted on said wedges 9 to be taken up during the compression of the layers 3 'and 4 and of the conformation of the piece 1.

In accordance with a very advantageous characteristic of the invention, apparent from FIGS. 1, 2A, 2B and 2H, the production of the components and / or elements 5 is carried out by injecting the thermoplastic material, via injection means 7 "Associated with the punch 7 ', in recesses or recesses 10 of suitable shapes present in said punch 7', separated or at least partly interconnected, these recesses or recesses 10 being sealed beforehand by parts of movable impressions 9 of the matrix during or after the closure of the mold device 6, to form one or more corresponding injection cavity (s) 10 '.

More specifically, the manufacturing method may advantageously consist, as illustrated in FIGS. 2A and 2H and for each production cycle of a part 1, to close the mold device 6, by putting the die 8 'in contact with the punch 7 ', to move the movable part (s) 9 of the cavity 9' of the die 8 'in its or their second position, so as to close the recess (es) or recesses respectively associated (s), then to inject a thermoplastic material to form the components and / or technical elements 5, then to open the mold device 6, after a predetermined cooling time, leaving in place on the punch 7 'said components and and / or technical elements 5 injected and moving the movable part (s) (s) in its or their second position, to then place on the punch 7 ', superimposed, a sheet of thermoplastic material and of natural fibers 3 'prech and a decor sheet 4, to pressurize the mold device 6 to conform the base body 3, to define the surface state and the relief of the apparent face 2 and to physically connect the components and / or the technical elements 5 to the base body 3, and finally, after cooling, to open the mold device 6 and extract the resulting hybrid or composite part 1, as a finished part.

Although the two parts 7 and 8 of the mold device 6 can be driven in translation to make the openings (uncoupling) and closures (couplings) of the injection molds and compression forming, or the first part 7 comprising the punch 7 and the injection means 7 ", it is preferentially provided that only the second part 8 with the matrix 8 'is mobile in translation for the sake of constructive simplicity and ease of operation. 2A to 2H, a production cycle can comprise the following consecutive operations: FIG. 2A: after extraction of the part 1 manufactured during the preceding cycle, closing of the mold and filling of the depressions 10 by the shims 9 in order to form the cavities 10 ', the elements and / or technical components 5 are injected During this time, the sheet 3' is being preheated (which ad broken during the previous cycle). 2B: opening of the mold by disengaging the second part 8 and retraction of the shims 9, stopping the heating of the sheet 3 'and removing the decor sheet 4 on the preheated sheet 3' (the elements and / or components 5 remain in place on the punch 7 'and partially cool). - Figure 2C: moving the conveyor belt 11, with the sheets 3 'and 4 superimposed, above the punch 7'. - Figure 2D: progressive removal of the sheets 3 'and 4 on the punch 7' (with the conveyor belt 11 and simultaneously moving the latter relative to the punch 7 '). - Figure 2E: closure of the mold with compression and forming of the sheets 3 'and 4, securing the elements and / or technical components 5 with the sheet 3' and cooling the resulting part 1. Simultaneously, placing a new sheet 3 'on the conveyor belt 11 and start of the pre-heating. - Figure 2F: opening of the mold by moving the second portion 8, demolding of the part 1, supported by the latter by manipulation means (frame) 14. The preheating of the sheet 3 'continues. - Figure 2G: the part 1 is removed from the mold by the frame 14 and the preheating of the sheet 3 'continues. - Figure 2H: identical to Figure 2A (beginning of a new manufacturing cycle and evacuation of the finished part 1).

The components and / or technical elements 5 not to be manipulated (extraction, displacement, ...) after their injection, their minimum cooling time can be considerably reduced (typically divided by about five).

It is even advisable, so that their adhesion material with the preheated sheet 3 'is optimal, that their cooling is not completed.

Moreover, since the injected technical parts are generally of small size and of reduced extension compared with the space requirement and the spatial extension of the spatial part 1, the pressure force necessary to keep the injection mold closed is limited and may be of the same order of magnitude as the pressure force necessary to achieve the compression forming. The mold device 6 can therefore be dimensioned (in terms of pressure) as a function of this last use of the mold device, which results in a limitation of the cost of the tooling and the press.

In order to optimize the process in terms of the duration of a manufacturing cycle, certain operations of two immediately consecutive cycles can be performed simultaneously, overlapping in time. For this purpose, the process may consist, preferably from the beginning of the second preceding cycle phase, in placing a sheet 3 'based on thermoplastic material and natural fibers, advantageously in the form of a fibrous mat based on thermoplastic fibers and of natural fibers intimately mixed, on a mobile or fixed support 11, for example of the plate or conveyor belt type, then to heat said sheet 3 'by radiation, contact or the like, until softening, or even melting, of the thermoplastic material and, at the beginning of the second current cycle phase, depositing said heated sheet 3 'on said punch 7', which carries the components and / or technical elements 5 injected during the first current cycle phase, for example by progressive unloading from the support mobile 11 and possible simultaneous movement of the latter relative to the punch 7 '.

In accordance with a first advantageous embodiment, particularly apparent from FIG. 3, the decor sheet 4 can be fed onto or into the die 8 'or disposed with support in the mold device 6 by means 12 adapted to of removable support equipping said die 8 'or associated with the mold device 6, preferably by hooking on a frame, the extraction and the evacuation of the resulting piece 1 being possibly made with the same removable support means 12, or similar 14 separate means.

In accordance with a second advantageous embodiment, illustrated in Figures 2C and 2D, the decor sheet 4 is deposited on the sheet 3 'based on thermoplastic material and natural fibers after heating the latter, the two sheets 4 and 3 superimposed are then deposited together on the punch 7 ', for example by progressive evacuation from the fixed or movable support 11, preferably by scrolling a carrier strip of the latter. The gradual evacuation of the sheet 3 'or the two superimposed sheets 3' and 4 of the support hub 11 can also be achieved by drawing by means of a clamp 13 or the like, in cooperation with a scrolling or not of the support strip of said hub 11 (Figure 3).

Depending on the desired finish for the workpiece 1, its function and / or its cooperation with other parts in its installation and mounting environment, it may be provided during the compression forming operation of the second cycle phase, to also perform a selective cutting operation and / or, before opening the mold device 6 for the extraction of the resulting part 1, to perform at least one cut in the part 1 after cooling.

Thus, by way of example, the mold device 6 can be equipped with a telescope 16 (see FIG. 3) making it possible to perform selective cutting or trimming when closing and coupling the two mold parts. 7 and 8.

Preferentially, the sheet 3 'based on thermoplastic material and natural fibers consists, before preheating, in a fibrous mat composed of a mixture of thermoplastic fibers and interlaced natural fibers, optionally incorporating fibers or reinforcing filaments, such as for example glass fibers, where appropriate arranged in lattice, as well as adjuvants and / or additives. The invention also relates, as shown in the accompanying figures, to a mold device 6, of the combination injection molding and thermocompression type, for the manufacture of hybrid parts 1 by means of the method described above.

The mold device 6 comprises, on the one hand, a first part 7 with a punch 7 'and a second part 8 with a matrix 8', and, on the other hand, means 7 "of thermoplastic injection material to through said punch 7 '.

The first and second parts 7 and 8 can be moved relative to one another to define at least open and closed states of the mold device 6, the shapes and topographies of the die 8 'and the punch 7 determining, respectively, on the one hand, the shape and the surface condition of the aspect face 2 and, on the other hand, the shape and configuration of the components and / or elements 5 of the technical face 2 ', as well as by mutual cooperation the general form of Exhibit 1.

In accordance with the invention, the matrix 8 'comprises at least one part of a movable internal surface imprint or topography, said one or more mobile part (s) being suitable (s) and intended (s) to participate defining the configuration of the impression 9 'determining the shape and the surface condition of the aspect face 2, in a first position, and closing off said recess (s) or recess ( s) to delimit one or more injection cavities 10 'for said components and / or technical elements (5), in a second position.

According to the invention, the mold device 6 further comprises means 11, 1Γ, 13 for supporting, heating and handling a sheet 3 'based on thermoplastic material and vegetable fibers, the support means and handling 11, 13 being further able to deposit said heated sheet 3 'on the punch 7' together with the decor sheet 4 or not.

According to a first variant of FIGS. 2, the support means 11 of the sheet 3 'based on thermoplastic material and natural fibers consists of a mobile conveyor belt, which can be moved over the punch 7' during the removal of said sheet 3 'heated, the heating being carried out by means of radiation heating, by contact or the like, located outside and at a distance from the parts 7 and 8.

According to a second variant emerging from FIG. 3, the support means 11 of the sheet 3 'based on a thermoplastic material and natural fibers consists of a movable or fixed plane support that can optionally be moved between a first position in which it is located under the heating means 11 'and a second position in which it is located above the punch 7', said plane support being associated means 13 for drawing the preheated sheet 3 ', from said support 11 to the punch 7' .

Said mold device 6 may further comprise means 12, 14 for handling, on the one hand, the decor sheet 4, on the other hand, the filling piece 1 'and, of the resulting piece 1, suitable and respectively for setting up the decor sheet 4 in the matrix 8 ', and extracting the piece 1 resulting from the matrix 8', these operations being performed by an operator or a robot (not shown).

Advantageously, said handling means 12, 14 consist of one or more movable frame (s) capable (s) to capture or support temporarily, respectively the decor sheet 4, or the resulting piece 1, preferably by hooking lateral. These frames can be moved by an operator, by a motorized mechanical device or by a robot.

Finally, the matrix 8 'may be provided with means for trimming and / or cutting opening (s) in the part 1 after compression, and optionally after cooling, such as for example a shaving bezel 16 and / or a cookie cutter (Figure 3). The invention also relates to a piece 1 of interior trim for a motor vehicle or the like, of surface type and of a hybrid or composite nature, this part having an apparent appearance face 2 and a rear technical face 2 '.

Said part 1 essentially comprises, on the one hand, a base body or substrate 3 obtained by thermocompression of a sheet 3 'based on thermoplastic material and natural fibers, on the other hand, a decorative sheet 4, reported on the base body 3 and defining the apparent face 2 and, finally, components or technical elements 5 reported on the rear face 2 'of the base body 3.

This piece 1 is characterized in that it is obtained by means of the method mentioned above, and by implementing a mold device 6 as described above, the thermoplastic materials of the sheet 3 'and components and or technical elements 5 being mutually compatible, or even identical.

Preferably, the substrate 3 consists of a thermocompressed fibrous mat based on thermoplastic and natural fibers and the decorative sheet advantageously consists of a polyvinyl chloride sheet, a thermoplastic polyolefin sheet or a textile, said part 1 further comprising if necessary, at least one cut and / or peripheral periphery at least partially cut away and optionally incorporating fibers and / or a reinforcement mesh.

The components and / or technical elements 5 may, where appropriate, form a structure, or even a layer in one piece extending over the entire surface of the rear face of the substrate 3. But for reasons of economy of material these components and / or elements 5 preferably constitute a fragmented or at least openwork structure.

Of course, the invention is not limited to the embodiments described and shown in the accompanying drawings. Modifications are possible, particularly from the point of view of the constitution of the various elements or by substitution of technical equivalents, without departing from the scope of protection of the invention.

Claims (20)

1) A method of manufacturing a part (1) surface, of a hybrid or composite nature, having an apparent appearance face (2) and a rear technical face (2 '), said part (1) essentially comprising, d on the one hand, a base body or substrate (3) obtained by thermocompression of a sheet (3 ') based on thermoplastic material and natural fibers, on the other hand, a decorative sheet (4), attached to the base body (3) and defining the apparent face (2) and, finally, components and / or technical elements (5) attached to the rear face (2 ') of the base body (3), said method comprising providing in advance a mold device (6) with a first portion (7) having a punch (7 ') and a second portion (8) having a die (8'), the first and second portions (7 and 8) being displaced relative to each other to define at least open and closed states of the mold device ( 6), the shapes and topographies of the matrix (8 ') and the punch (7') respectively determining, on the one hand, the shape and the surface condition of the aspect face (2) and, d on the other hand, the shape and configuration of the components and / or elements (5) of the technical face (2 '), as well as by mutual cooperation the general shape of the workpiece (1), characterized in that it consists of to provide a mold device (6) with, on the one hand, a matrix (8 ') having at least one movable inner surface imprint or topography part (9) and, on the other hand, a punch (7 ') provided with one or more recesses (s) or recesses (10) whose shapes and positions correspond to those of the components and / or technical elements (5) to be injected from the workpiece (1), the movable part (s) (9) being suitable and intended to participate in the definition of the configuration of the impression (9 ') determining the shape and surface condition of the the asp face ect (2), in a first position, and closing off the aforementioned rerifoncement (s) or recess (10) to delimit one or more injection cavities (10 ') for said components and / or technical elements (5), in a second position, and in that it consists, during a first cycle phase, in using the mold device (6) as an injection mold, for injecting the components and / or technical elements (5), while the movable part (s) (9) are in their second position, and during a second cycle phase, using the mold device (6) as a forming mold by compression, to conform the decor sheet (4) and the sheet (3 ') made of thermoplastic material and natural fibers, after preheating thereof, and to assemble the components and / or technical elements (5) produced during the first cycle phase with this sheet (3 ') preheated, while the mobile part or parts (9) are in their first e position. 2) Method according to claim 1, characterized in that the displacement of the portion (s) of impression (s) movable (s) (9) of the matrix (8 ') between his or their first and second positions consists of a linear translation movement of said one or more portions (9) relative to the rest of the die (8 '), between a retracted position and an extended position. 3) Method according to claim 1 or 2, characterized in that in its or their first position, the part (s) of the movable cavity (s) (9) of the matrix (8 ') are flush (s) and contiguous with the surrounding area (s) of the inner surface of the remainder of the footprint (s), and that in its second position the movable part (s) (s) (9) are projecting relative to said at least one surrounding area (s). 4) Process according to any one of claims 1 to 3 characterized in that it consists in providing a matrix (8 ') provided with part (s) of movable fingerprint (s) (9) mounted (s) with faculty guided sliding in corresponding housings (9 ") of the body of the die (8 ') and in effecting the displacement of said at least one movable part (s) (9) via actuator (s) electrical, hydraulic or pneumatic type, controlled individually or in a grouped manner. 5) Process according to any one of claims 1 to 4, characterized in that it consists in producing the components and / or technical elements (5) by injecting the thermoplastic material, via injection means (7). ") associated with the punch (7 '), in recesses or recesses (10) of suitable shapes present on said punch (71), separated or at least partly interconnected, these recesses or recesses (10) being previously closed sealingly by movable finger portions (9) of the die (8 ') during or after the closing of the mold device (6) to form one or more corresponding injection cavities (10') . 6) Process according to any one of claims 1 to 5, characterized in that it consists, for each production cycle of a part (1), to close the mold device (6), putting the matrix ( 8 ') in contact with the punch (T), to move the movable part (s) (9) of the impression (9') of the die (8 ') in its second position or in order to close off the recess (es) or hollow respectively associated (s), then to inject a thermoplastic material to form the components and / or technical elements (5), then to open the mold device (6), after a predetermined cooling time, leaving in place on the punch (T) said components and / or technical elements (5) injected and moving the movable part (s) (9) in its or their first position , then put on the punch (T), superimposed, a sheet of thermoplastic material and natural fibers (3 ') preheated and a decor sheet (4), to pressurize the mold device (6) to conform the base body (3), to define the surface condition and the relief of the apparent face (2) and to physically connect the components and / or technical elements (5) to the base body (3), and finally, after cooling, opening the mold device (6) and extracting the resulting hybrid or composite part (1), as a that piece finished. 7) Method according to any one of claims 1 to 6 characterized in that it consists, preferably from the beginning of the second phase of the previous cycle, to place a sheet (3 ') based on thermoplastic material and fibers natural, advantageously in the form of a fibrous mat based on thermoplastic fibers and natural fibers intimately mixed, on a mobile or fixed support (11), for example of the plate or conveyor belt type, then heating said sheet (3 ') by radiation , contact or the like, until softening or melting the thermoplastic material and, at the beginning of the second phase of the current cycle, depositing said heated sheet (3 ') on said punch (7'), which carries the components and / or technical elements (5) injected during the first phase of the current cycle, for example by progressive unloading from the mobile support (11) and possible simultaneous movement of the latter with respect to the punch (7 '). 8) Process according to any one of claims 1 to 7, characterized in that the decorative sheet (4) is fed to or in the matrix (8 ') or arranged with holding in the mold device (6) by the intermediate means (12) adapted removable support equipping said die (8 ') or associated with the mold device (6), preferably by hooking on a frame, the extraction and evacuation of the piece (1) resulting, being possibly made with the same removable support means (12), or similar separate means (14), 9) Process according to any one of claims 1 to 7, characterized in that the decor sheet (4) is deposited on the sheet (3 ') based on thermoplastic material and natural fibers after heating the latter, the two sheets (4 and 3 ') superimposed then being deposited together on the punch (7'), for example by progressive evacuation from the fixed or movable support (11), preferably by scrolling a carrier strip of the latter or by drawing by means of a clamp (13) or the like. 10) Method according to any one of claims 1 to 9, characterized in that it consists, during the compression forming operation of the second cycle phase, to also perform a selective trimming operation and / or before opening the mold device (6) for extracting the workpiece (1) resulting in at least one cut in the workpiece (1) after cooling. 11) Method according to any one of claims 1 to 10, characterized in that the movable part (s) imprint of the matrix (8 ') and the recess or recesses (s) (10) of the punch (7 ') are provided on their peripheries, complementary means forming by mutual cooperation a seal. 12) Process according to any one of claims 1 to 11, characterized in that the sheet (3 ') based on thermoplastic material and natural fibers consists, before preheating, in a fibrous mat composed of a mixture of thermoplastic fibers and interlaced natural fibers, optionally incorporating reinforcing fibers or filaments, such as, for example, glass fibers, optionally arranged in lattices, as well as adjuvants and / or additives. 13) A mold device for the manufacture by means of the method according to any one of claims 1 to 12, of a hybrid or composite surface part (1) having an apparent appearance face (2) and a technical face rear part (2 '), said part (1) essentially comprising, on the one hand, a base body or substrate (3) obtained by thermocompression of a sheet (3') based on thermoplastic material and natural fibers, d on the other hand, a decoration sheet (4), attached to the base body (3) and defining the apparent face (2) and, finally, components and / or technical elements (5) attached to the rear face (2 ') of the base body (3), said mold device (6) comprising, on the one hand, a first part (7) with a punch (7') and a second part (8) with a matrix ( 8 '), and, on the other hand, means (9) for injecting thermoplastic material through said punch (7'), the first and second parts (7 and 8) being able to Instead of being displaced relative to each other to define at least open and closed states of the mold device (6), the shapes and topographies of the die (8 ') and the punch (7') determining respectively, on the one hand, the shape and the surface condition of the appearance face (2) and, on the other hand, the shape and configuration of the components and / or elements (5) of the technical face ( 2 '), as well as by mutual cooperation the general shape of the part (1), mold device (6) characterized in that the matrix (8') comprises at least one part of impression or movable internal surface topography , said one or more movable part (s) being suitable (s) and intended (s) to participate in the definition of the configuration of the imprint (9 ') determining the shape and the surface condition of the face (2), in a first position, and closing a recess (s) or recess (10) of the punch (7 ') to delimit one or more injection cavities (10 ') for said components and / or technical elements (5) in a second position, and in that it comprises means (11, 1Γ, 13) for supporting, heating and handling a sheet ( 3 ') based on thermoplastic material and vegetable fibers, the support and handling means (11, 13) being further able to deposit said preheated sheet (3') on the punch (7 '), together with the sheet decor (4) or not. 14) A mold device according to claim 13, characterized in that the support means (11) of the sheet (3 ') based on thermoplastic material and natural fibers consists of a movable conveyor belt which can be moved over the punch (7 ') during the removal of said heated sheet (3'), the heating being carried out by means (1Γ) of heating by radiation, contact or the like, located outside and at a distance from the two parts (7 and 8). 15) A mold device according to claim 13, characterized in that the support means (11) of the sheet (3 ') based on thermoplastic material and natural fibers consists of a movable or fixed planar support that can optionally be moved between a first position in which it is located under the heating means (1Γ) and a second position in which it is located above the punch (7 '), said planar support being associated with a means (13) for pulling the sheet ( 3 ') preheated from said support (11) to the punch (T) - 16) Mold device according to any one of claims 14 and 15, characterized in that it further comprises means (12, 14) for handling, on the one hand, the decor sheet (4) and, on the other hand, of the piece (1) resulting, suitable and respectively for setting up the decor sheet (4) in the matrix (8 ') and for extracting the composite part (1) resulting from the matrix (8) '), these operations being carried out by an operator or by a robot. 17) mold device according to claim 16, characterized in that the handling means (12, 14) consist of one or more mobile frame (s) capable (s) to seize or temporarily support, respectively the decorative sheet (4) or the resulting part (1), preferably by lateral attachment. 18) mold device according to any one of claims 14 to 17, characterized in that the die (8 ') is provided with means for trimming and / or cutting aperture (s) in the piece (1) after its compression, and optionally after cooling, such as for example a shaping bezel and / or a punch. 19) Interior trim piece for a motor vehicle or the like, of surface type and of a hybrid or composite nature, this part comprising an apparent appearance face (2) and a rear technical face (2 '), said part (1) comprising essentially, on the one hand, a base body or substrate (3) obtained by thermocompression of a sheet (3 ') based on thermoplastic material and natural fibers, on the other hand, a decor sheet (4), attached to the base body (3) and defining the apparent face (2) and, finally, components or technical elements (5) attached to the rear face (2 ') of the base body (3), part (1) ) characterized in that it is obtained by means of the method according to any one of claims 1 to 12, and by implementing a mold device (6) according to any one of claims 13 to 18, the thermoplastic materials of the sheet (3 ') and components and / or technical elements (5) and mutually compatible or even identical. 20) Piece sëlon claim 19, characterized in that the substrate (3) consists of a fibrous mat thermocompressed based on thermoplastic and natural fibers and in that the decorative sheet consists of a sheet of polyvinyl chloride, a sheet thermoplastic polyolefin or a textile, said piece (1) further including, where appropriate, at least one cutout and / or peripheral periphery at least partially cut away and optionally incorporating fibers and / or a reinforcement mesh.