FR2869776A1 - Slash-resistant covering for seats in public transport vehicles includes layer of knitted metal filaments partially impregnated by elastomer material - Google Patents

Abstract

The covering material complex (1) consists of a layer (5) of a supple and impermeable material, a layer (2) of knitted metal filaments, a layer (8) of an elastomer material that partly impregnates the knitted layer, and a supple outer layer (7). The knitted layer includes filaments of high-strength steel 0.25 - 0.5 mm, and preferably 0.35 mm in diameter, and textured multi-filaments of high-strength synthetic fibres in a jersey knit. The elastomer layer is about 2 mm thick, and the inner supple and impermeable layer is of a polymer material 0.1 - 3 mm thick. The different layers of material are assembled in a frame and then formed into seat components in a mould into which a foam is injected.

Description

The present invention relates to an anti-laceration complex for particular

  transit vehicle seat, a method of making the complex, and a method of manufacturing a seat using the complex.

  The seats of public transport vehicles (metro, buses, urban trains) must be covered with a complex that ensures insensitivity to acts of vandalism. The most common act of vandalism is the attempt to lacerate a siege with a stab.

  It is therefore known to cover this type of seat with a complex comprising a knit of metal son. The presence of this metal knit gives the complex a good resistance vis-à-vis laceration attempts. The counterpart of this quality is that it has a mediocre flexibility and therefore the seats using these complexes are very uncomfortable.

  From the point of view of the manufacture of such complexes, it should be noted that the handling of metal knits poses a major problem since these being made of knitted or woven wire, each wire tends to behave like a spring. . They have a very marked tendency to curl. This requires to provide complex and unreliable assemblies ensuring the retention of metal knits.

  It is also known from documents EP-A-981 982 and EP-A-1 127 517 that it is possible to place in a mold the various constituents of the anti-laceration complex and to matrix them to give the complex a three-dimensional shape which corresponds to the shape of the seat to be covered. In this embodiment, it proves difficult to control the contribution of elastomeric materials in particular, which are in liquid or pasty form. It can result in a variation in thickness of these materials, which can have a detrimental effect on the flexibility of the complex.

  The object of the invention is therefore to propose an anti-laceration complex which is inexpensive to manufacture and which has a greater flexibility than that of the known complexes.

  The invention therefore relates to an anti-laceration complex intended to cover a seat, in particular a public transport vehicle, one of the so-called inner faces facing a seat upholstery and the other so-called outer face forming the face of the seat. seat of the seat, characterized in that it comprises: - a layer of flexible and waterproof material, - a knit of metal son, - a layer of elastomeric material partially impregnating the knit, - a flexible coating forming the outer face of the complex .

  The technical effect of the combination of the components of this complex is that, thanks to the partial impregnation of the wires, a certain mobility of the latter is possible, which has the effect of increasing the anti-laceration characteristics of the complex . Indeed, when introducing a blade or a punch, the metal son can move slightly relative to each other, without being cut by the blade or the punch.

  The partial coating of the metal son is made possible by the fact that the metal knit has, on its face opposite to that in contact with the elastomeric material, a layer of flexible and waterproof material which prevents complete flooding of the knit in the elastomer.

  Another very important feature of the invention provides that the knit fabric comprises high strength steel wires combined with textured multi-filament yarns of high tenacity synthetic fibers.

  Preferably, the synthetic fiber yarns consist of aramid fibers.

  According to another very advantageous characteristic, the knit is a knit jersey forming stitches from metal threads with a diameter of between 0.25 and 0.5 millimeters and textured multi-filament yarns of high tenacity synthetic fibers.

  The small diameter of the metal wires gives the complex a great deal of flexibility. It should be noted that this flexibility is not obtained to the detriment of the anti-laceration resistance since, thanks to the synthetic fibers and thanks to the possible mobility of the metal wires, a blade entering this complex is stopped and if it continues its movement, wires may move slightly without cutting immediately.

  Preferably, the diameter of the wires is equal to 0.35 millimeters.

  According to one characteristic of the invention, the thickness of the layer of elastomeric material is between 1.5 and 3 millimeters.

  Preferably, the thickness of the elastomer layer is about 2 millimeters.

  Thus, in the case of cutting a wire constituting the knit, the end of the sectioned wire remains trapped in the elastomer layer.

  According to another possibility, the layer of flexible and waterproof material has a thickness of between 0.1 millimeter and 3 millimeters and is made of PVC, polyester or polyurethane.

  The invention also relates to a method for producing the complex defined above comprising the steps consisting in: a) pre-assembling a layer of flexible and impervious material on a knit of metal threads in order to form a sub-complex which can be manipulated in particular by suction, b) placing a flexible coating in a frame, c) extending a layer of elastomeric material on the flexible coating, d) depositing the sub-complex obtained in step a) on the layer of elastomeric material, such so that the metal knit penetrates the elastomeric material.

  The complex can therefore be manufactured extremely simply by a succession of flat operations that do not require expensive equipment. Moreover, thanks to this method, it is possible to manufacture the complex according to the specific dimensions, for example of a cushion element to be covered. This process makes it possible to optimize the quantity of material involved thus avoiding falling material.

  The complex according to the invention can be implemented according to a process comprising the steps of: - setting up the complex as defined previously on a support frame, - deforming this complex by a seat structure element having a wall of the bottom surrounded by a peripheral rim, - backfilling the complex on the outer face of the peripheral rim and the bottom wall, so as to form a sealed cavity delimited by the structural element of the seat and by the complex, - inject into the cavity a foam forming the lining of the seat element, - carry out the polymerization of the foam.

  In addition, the structural element is a structural element of a seat, a backrest element or headrest.

  For a good understanding, the invention is described with reference to the accompanying drawing showing, by way of non-limiting example, an embodiment of a complex according to the invention.

  Figure 1 is a top view of this complex, Figure 2 is a sectional view along II-II of Figure 1, Figure 3 is a view of a knit constituting this complex, Figures 4 and 5 show manufacturing steps of a seat using this complex, Figure 6 is a sectional view.

  Referring first to Figure 2, it can be seen that the complex according to the invention comprises four constituents.

  This complex comprises a metal knit 2 which has, as a peculiarity, to be a jersey knit forming stitches from high strength steel wires 3 and high tenacity multi-filament yarns 4 of synthetic fibers. These fibers are preferably aramid fibers. On the face of the metal fabric 2 intended to be in contact with a gasket, it is noted that the metal fabric 2 receives a layer 5 of flexible and waterproof material. Preferably, it is polyethylene foam. This layer 5 has, as a technical effect quite remarkable, the fact of making the metal fabric manipulable.

  Indeed, a knit 2 made of metal son is inherently difficult to handle since each of the constituent metal son tends to behave like a spring, so that these metal knits tend to wrap at their edge.

  However, the presence of the layer 5 makes it possible to stabilize the metal knit 2 and has, as a second technical effect, the fact of being able to move the sub-complex formed by the metal knit 2 and by the layer 5, by suction devices, which prove extremely useful for moving and positioning such a sub complex.

  It should also be noted that, quite remarkably, the diameter of the metallic threads constituting the knit is substantially less than the diameter of the threads constituting the knits used in the known complexes.

  Indeed, in the case of the complex according to the invention, the diameter of the son 3 is between 0.25 and 0.5 millimeters, but preferably equal to 0.35 millimeters. The yarns usually used are of much larger diameters since, for example, in EP-A-1 127 517 there is provided a wire having a diameter of about 0.7 millimeter. This characteristic will have, as we shall see, a quite substantial effect on the properties of this complex.

  The other constituents of this complex are, on the one hand, a flexible textile covering 7. This is a natural or synthetic textile velvet type, well known, whose opposite side to the outward facing of the complex receives a layer 8 of elastomeric material. It is a polymer that can be an anti-fire silicone having, in the polymerized state, a significant resistance to delamination.

  This layer 8 has a thickness that can be between 1 and 3 millimeters, but preferably is equal to 2 millimeters. The thickness of 2 millimeters gives the complex a good flexibility.

  During the manufacture of this complex, the flexible textile covering 7, cut into a shape adapted to its future function, is placed in a frame; the layer 8 of elastomeric material is then coated thereon. This operation can be performed manually or mechanically with quite simple means, since these are operations performed only flat.

  This operation of coating the textile coating 7 being performed, the sub-complex defined above is brought and is deposited on the layer 8 of elastomeric material; the metal knit then penetrates into the elastomeric material.

  It should be noted that this penetration of the elastomeric material into the loops formed by the metallic threads 3 and by the threads 4 does not occur over the entire surface of the threads since it should be remembered that the metal threads and the threads 4 are also backed by the layer 5 of flexible material.

  Thus, an important point to emphasize is that the wires and wires 4 are not completely embedded in the layer 8 of elastomeric material. Admittedly, they include most of the metal son 3 and synthetic son 4, but a portion of it emerges from the layer 8 of elastomer, the latter part being the one in contact with the layer 5 of flexible material.

  The essential property of this complex is its flexibility, which is conferred on it by the use of a knit of which the wire 3 is of a diameter much smaller than the diameter of the metal wires used in the previously known complexes.

  Nevertheless, despite the use of a metal wire knit having small diameter threads, the behavior of this complex with respect to aggression by a knife is quite remarkable.

  Indeed, in the case where a knife blade would be introduced into the complex, it would be stopped by the metal and synthetic knitting and when we would like to move this blade in the complex from the punching point, this displacement would be interrupted by the loops of metallic threads 3 and synthetic threads 4.

  It is important to note that the fact that metal wire loops and synthetic fibers are not fully impregnated in the elastomeric material, means that they have a certain ability to move and therefore not to be cut by the action of the blade.

  Nevertheless, if one of the metal wires 3 were to be cut, there would be no risk that it would come and break out of the surface of the complex, since the end of this broken wire would be absorbed in the thickness of elastomeric material.

  Standardized tests show in this respect the very satisfactory behavior of this complex. Indeed the complex thus defined is in accordance with the NF-F-31118 standard and this having an exceptional flexibility.

  This complex and its manufacturing method therefore have the many advantages indicated above since, on the one hand, the complex has satisfactory anti-laceration properties, while being more flexible than the complexes of the prior art. This allows on the one hand to give it three-dimensional shapes and on the other hand, the method to achieve it includes only flat work steps requiring inexpensive tools, and in any case much inferior to the molding process in situ complex, as it can be described in the document EP-A-1 127 517. Furthermore, the manufacturing process ensures excellent control of the thickness of the constituents brought in liquid or pasty form, in particular the elastomer . The great control of the thickness of the constituents of the complex makes it possible to have an optimal flexibility since any risk of excess thickness, in particular of elastomer which would be detrimental to the flexibility, is discarded.

  A second quite remarkable aspect of this complex is that, thanks to the layer of flexible and waterproof material present on the underside of the metal knit, this complex can be used in a very original way, for the manufacture a seat element, whether it is a seat element, backrest or headrest.

  Indeed, it has been seen that this layer 5 confers a tightness to the complex which is used in particular to manipulate the sub-complex formed of the layer 5 and the knitted fabric of the yarns 3 and fibers 4.

  Another aspect of the invention therefore relates to a method that provides, in a first step, to place the complex on a frame 13, the edges of the complex being retained by elastic flanges, that is to say flanges s' erase when exerting pressure on the complex.

  The second step is therefore to bring a seat structure element 9, a seat or backrest element, this element comprising a bottom wall 10 and a peripheral flange 1 1 surrounding the bottom wall 10. This is there of the structural element forming the part of the seat in question.

  As illustrated in FIG. 4, this structural element 9 is brought against the complex 1 stretched over a frame 13 and is pushed against the complex so that the complex comes to conform to the shape of the structural element 9; it is specified that the complex is dimensioned such that it exceeds the footprint made by the structural element 9 on the complex.

  In a third step, the edges of the complex 1 protruding from the structural element are folded over the flange 11 and on the outer face of the bottom wall 10 of the structural element 9. Thus, a sealed cavity is formed delimited by the structural element 9 and the complex 1. Through an opening 14 provided in the structural element 9, polyurethane foam 12 is injected, this polyurethane foam 12 to form the seat lining. It can thus be seen that, thanks to this method, a seat element, represented in FIG. 6, has been formed in one operation without taking up any of the constituent elements of the seat element in question.

  Ultimately, this complex that can be achieved in a simple manner using operations exclusively flat can make it possible to achieve seat and file elements in a way also quite simple, fast and economical.

  Of course, this complex can be implemented conventionally or in the form of a traditional cover formed of panels assembled by stitching or by the draper on a trim element. These operations are extremely easy to achieve thanks to the flexibility of the complex allowing him to marry the left forms.

Claims (11)

  1. complex (1) anti laceration intended to cover a seat, including a public transport vehicle, one of the so-called inner faces is opposite a seat lining and the other face said outer face is the face of seat seat, characterized in that it comprises: a layer (5) of flexible and waterproof material, - a knit (2) of metal threads (3), - a layer (8) of elastomer material partially impregnating the knit ( 2), - a flexible coating (7) forming the outer face of the complex.   2. anti-laceration complex according to claim 1, characterized in that the knit (2) comprises high strength steel son (3) associated with threads (4) multifilament textured high tenacity synthetic fibers.   3. anti-laceration complex according to claim 2, characterized in that the yarns (4) of synthetic fibers consist of aramid fibers.   4. Anti-laceration complex according to claim 2 or claim 3, characterized in that the knit (2) is a jersey knit forming stitches from metal threads (3) with a diameter of between 0.25 and 0.5 millimeters. and multi-filament yarns (4) of high tenacity synthetic fibers.   5. anti-laceration complex according to claim 4, characterized in that the diameter of the son (3) is equal to 0.35 millimeter.   6. anti-laceration complex according to one of claims 1 to 5, characterized in that the thickness of the layer (8) of elastomeric material is between 1.5 and 3 millimeters.   7. anti-laceration complex according to claim 6, characterized in that the thickness of the layer (8) of elastomer is about 2 millimeters.   8. anti-laceration complex according to one of claims 1 to 7, characterized in that the layer (5) of flexible and waterproof material has a thickness of between 0.1 millimeter and 3 millimeters and is made of PVC, polyester or polyurethane.   9. A method of producing an anti-laceration complex according to one of claims 1 to 8, characterized in that it comprises the steps of: a) to perform a pre-assembly of a layer (5) of flexible and waterproof material on a knit (2) of metal threads to form a sub-complex manipulable in particular by suction, b) to place a flexible coating (7) in a frame, c) to extend a layer (8) of elastomeric material on the coating flexible (7), d) depositing the sub-complex obtained in step a) on the layer of elastomeric material (8), so that the knit (2) partially penetrates the elastomeric material.   10. A method of producing a seat element including a public transport vehicle, characterized in that it comprises the steps of: - set up the complex (1) according to claims 1 to 8 on a frame ( 13), - stamping the complex (1) by a seat structure element (9) having a bottom wall (10) surrounded by a peripheral flange (11), to bridge the complex (1) on the outer face of the peripheral rim (11) and the bottom wall (10), so as to form a sealed cavity delimited by the element (9) of the seat structure and the complex (1), - inject into the cavity a foam (12) forming the filling of the seat element, - carrying out the polymerization of the foam (12).   11. The method of claim 10, characterized in that the element (9) structure is a structural element of seat, a backrest element or headrest.