PREFORMED ELEMENT FOR THE INTERIOR TRIM OF MOTOR CARS AND A METHOD FOR ITS MANUFACTURE

Abstract: A preformed element for the interior trim of motor cars comprises a shaped base of thermoplastic material (4) produced by injection moulding and having openings (7), and flat panels (5) carrying a soft covering (6) and applied to the back face of the base (4) in correspondence with the openings (7). The flat panels (5) are fixed by hot deformation of integral retaining appendages (8) projecting from the back face of the base (4), or by welding, gluing or similar means.

Description: The present invention relates generally to interior trim elements for motor cars. More particularly, the subject of the invention is a preformed element useable as a panel for covering the internal face of a door or for other parts of the interior trim of a motor car and a method for its manufacture. According to known techniques, these preformed elements are produced by the moulding of sheets of thermoplastic material (for example, polypropylene) to the outer face of which a soft covering is subsequently applied. This covering may be constituted by a single layer applied to the entire surface of the moulded sheet, or of layers of smaller dimensions applied to preselected regions of the sheet. These known trim elements have the disadvantage of being fairly expensive, particularly because the way in which the soft covering is applied requires complex upholstery and finishing operations. DE-U-8522207 shows a preformed element comprising a shaped base having at least one opening and at least one flat panel carrying a soft covering, applied to the back face of the base in correspondence with a respective opening. The joining between the base and each panel is obtained by means of the engagement between a grooved flange of the panel and a check rib provided on the inner side of the base, requiring then a complex and relatively expensive construction. The object of the present invention is to produce a preformed interior trim element for motor cars which, compared to conventional trim elements, is simpler and cheaper to make, more readily adaptable to the functional and aesthetic requirements of use, and also has a lighter structure. This object is achieved according to the invention by means of the features set forth in the characterising portion of claim 1. The preformed element according to the invention can be produced by simpler and cheaper operations than conventional trim elements, and has a lighter structure than the latter. Injection moulding of the base enables its shape to be adapted easily to the functional and aesthetic requirements of use, and the way in which the or each panel with its soft covering is fitted enables complex and laborious upholstery and final finishing operations to be avoided. The method for the production of the preformed trim element according to the invention is defined in claim 3. The preformed element according to the invention is useable to advantage both for the production of internal door-covering panels, and for the production of other parts of the interior trim of the passenger compartments of cars. The invention will now be described in detail with reference to the appended drawings, provided purely by way of non-limiting example, in which: Figure 1 is a schematic perspective view which shows the inside of a motor car provided with preformed trim elements according to the invention, Figure 2 is a front elevational view of one of the trim elements of Figure 1, on an enlarged scale, Figure 3 is an exploded perspective view of Figure 2, Figure 4 is a longitudinal section taken on the line IV-IV of Figure 2, and Figures 5 and 6 are two cross-sections taken respectively on the lines V-V and VI-VI of Figure 2. With reference initially to Figure 1, a part of the passenger compartment of a motor car equipped with preformed trim elements according to the invention is schematically indicated A. In particular, these elements comprise a panel 1 for covering the inside of one of the front doors P₁ of the car and a panel 2 covering the inside of one of the rear doors P₂ of the car. The two elements 1 and 2 have different configurations but are produced by identical techniques and with identical components, as described below with reference to the element 1 illustrated in greater detail in Figures 2 to 6. The element 1 is constituted essentially by a shaped base 4 and by a pair of flat panels 5 carrying respective soft coverings 6 and applied in correspondence with two regions circumscribed by the base 4. The base 4 is made of thermoplastic material, for example of polypropylene, and is produced by an injection moulding method of a type known to the expert in the art. This moulding is carried out so that, in correspondence with the regions intended to receive the flat panels 5, the sheet 4 has corresponding openings 7. Furthermore, still during moulding, integral projecting retaining appendages 8, whose function will become clear from the following, are formed on the inner face of the base 4, in correspondence with the edges of the openings 7. Each flat panel 5 is constituted by a rigid substrate 9, normally of masonite or a similar material, to one face of which the covering 6 is applied. The latter conveniently comprises a layer of soft material, such as wadding or the like, to which is heat-welded a layer of natural or synthetic fabric defining the covering 6 proper. The arrangement is such that, between the outer edge of the cover 6 and that of the substrate 9, is defined a peripheral bearing flange 10 which has through-holes 11 arranged like the retaining appendages 8 of the corresponding opening 7. The application of the panels 5 to the base 4 is effected by inserting the panels 5 from the rear of the back face of the base 4, in correspondence with the respective openings 7, and inserting the retaining appendages 8 through the holes 11 of the flanges 10. The flanges 10 are then pushed into contact with the edge of the respective openings 7, so as to position the coverings 6 through the openings. Permanent fixing of the panels 5 to the base 4 is effected by simple hot deformation of the free ends of the retaining appendages 8 against the flanges 10. The element 1 is then completed by the application of accessories, such as an armrest-handle M, the operating crank L for the window of the door P₁, and a possible lower pocket T for holding articles. As stated above, the element 2 of Figure 1 is produced in an identical manner to that described above with reference to the element 1, and differs from the latter only in the different shapes of the base 4 and of the panels 5 with the soft covering 6, and in the arrangement and configuration of the accessories.

Claims: A preformed element for the interior trim of motor cars, comprising a shaped base of thermoplastic material (4) produced by injection moulding and having at least one opening (7), and at least one flat panel (5) carrying a soft covering (6) and applied to the back face of the base (4) in correspondence with the or a respective opening (7), wherein the base is provided with integral retaining elements (8) projecting from its back face in the region of the or each opening (7), and the or each flat panel (5) is provided with corresponding retaining portions (11), each retaining element (8) being inserted into a respective retaining portion, characterised in that said retaining elements are appendages (8), said retaining portions are holes (11) through which the appendages pass and said appendages are hot deformed against the or each corresponding panel (5) so as to fix the or each panel (5) to the base (4). An element according to Claim 1, characterised in that the or each panel (5) comprises a rigid substrate (9) having a peripheral flange (10) which bears against the edge of the or the respective opening (7) of the base (4) in engagement with the integral retaining appendages (8), and to which the covering (6) is fixed so as to project through the or the respective opening (7) relative to the bearing flange (10). A method for the production of a preformed element for the interior trim of motor cars comprising the steps of: forming a shaped base (4) having at least one opening (7), by injection moulding a thermoplastic material, producing at least one flat panel (5) comprising a rigid substrate (9) and a soft covering (6) applied to the substrate (9), fixing the or each flat panel (5) to the back face of the base (4) in correspondence with the or a respective opening (7) so that the soft covering of the or each flat panel is disposed within the respective opening (7), forming the base (4) with integral retaining elements (8) projecting from its back face in the region of the or each opening (7), forming the or each flat panel (5) with a peripheral flange (10) and retaining portions (11) corresponding to the aforesaid retaining elements (8) of the base (4), inserting the or each flat panel (5) in the or each respective opening (7) of the base (4) placing the peripheral flange (10) of the or each panel (5) in bearing contact against the edge or edges of the or each respective opening (7) of the base, characterised in that the retaining elements (8) comprise appendages, the retaining portions (11) comprise holes, each appendage engaging a corresponding hole and that the or each flat panel is fixed to the base (4) by hot deformation of each retaining appendage (8).

Inventors: BARBERIS, FRANCO
Applicants: FIAT AUTO S.P.A.
Application year: 1988
Main classification: B60R13
IPC codes: B60R13, B60J5