EP0105007B1 - Process for the manufacture of a plastic wave reflector, and reflector made by this method - Google Patents

Process for the manufacture of a plastic wave reflector, and reflector made by this method Download PDF

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Publication number
EP0105007B1
EP0105007B1 EP19830401887 EP83401887A EP0105007B1 EP 0105007 B1 EP0105007 B1 EP 0105007B1 EP 19830401887 EP19830401887 EP 19830401887 EP 83401887 A EP83401887 A EP 83401887A EP 0105007 B1 EP0105007 B1 EP 0105007B1
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EP
European Patent Office
Prior art keywords
main structure
reflecting surface
mold
sheet
tissue
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Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired
Application number
EP19830401887
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German (de)
French (fr)
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EP0105007A1 (en
Inventor
Robert Herold
Serge Culos
Bernard Bancal
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Thales SA
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Thomson CSF SA
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    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q15/00—Devices for reflection, refraction, diffraction or polarisation of waves radiated from an antenna, e.g. quasi-optical devices
    • H01Q15/14—Reflecting surfaces; Equivalent structures
    • H01Q15/141—Apparatus or processes specially adapted for manufacturing reflecting surfaces
    • H01Q15/142—Apparatus or processes specially adapted for manufacturing reflecting surfaces using insulating material for supporting the reflecting surface
    • H01Q15/144—Apparatus or processes specially adapted for manufacturing reflecting surfaces using insulating material for supporting the reflecting surface with a honeycomb, cellular or foamed sandwich structure

Definitions

  • the present invention relates to a process for manufacturing a plastic wave reflector, as well as a reflector obtained by this process, such a reflector being in particular intended for use in radar or in telecommunications.
  • reflectors of the “sandwich” type for example by document FR-A-2168 891, which comprises a first metal sheet intended to form the reflector, placed on a mold, a second sheet intended to form the face rear of the reflector, arranged at a certain distance from the first sheet, the space between the two sheets being filled with a plastic material.
  • Reflectors of the “sandwich” type are also known comprising a core of honeycomb materials, covered with fabrics impregnated with polyester or epoxy resins.
  • these reflectors are formed by successive assemblies of the constituent elements defined above on a metal or plastic mold, machined with great precision according to the profile of the part to be obtained. After hardening of the impregnation and bonding resins, the reflector is removed from the mold.
  • the object of the invention is a process for manufacturing plastic wave reflectors combining high dimensional stability with high form accuracy, which avoids the drawbacks mentioned, in particular the machining operations necessary to remedy the defects observed after the steaming.
  • the main structure is produced, the reflective surface is produced, then the main structure is assembled with the reflective face by gluing the reflective face using an adhesive which expands at room temperature, by positioning precisely the main structure without contact on the reflecting skin, the adhesive expanding and then polymerizing.
  • This assembly 6 is hardened, substantially at room temperature, then removed from the mold and placed on a simple support where it undergoes the steaming operation until complete polymerization.
  • Figure 2 schematically shows the assembly operation of the main structure 6 of Figure 1 with a reflective surface.
  • FIG 3 shows schematically the finished product, that is to say the reflector obtained by applying the method according to the invention. It is noted that the expanded adhesive 9 occupies the entire interval 8 and that it has penetrated through the holes 5 provided in the first skin 1 of the main structure 6, to create anchor points 10 of the surface 7 in the core 2 of the main structure 6.
  • the adhesive used which expands during processing, without being as liquid as a normal adhesive, may however have a sufficient degree of fluidity before expansion to risk not remaining in place when the surface of the surface reflective on which it is extended has a significant curve.
  • Figures 4, 5 and 6 schematically show the different stages of producing a reflector according to this variant of the method according to the invention.
  • FIG. 4 represents the main structure produced in accordance with the variant of the method according to the invention.
  • This structure comprises a thin sheet 11 of honeycombs, plastic or metallic, deposited on a precision mold (not shown), glued to the first skin 1, the core 2 of honeycomb material glued to the skin 1 and the second skin 3 bonded to the core 2.
  • the reflective surface 7 is produced in the manner which has been described previously. The assembly of the structure with the reflecting surface is then carried out.
  • FIG. 5 represents the positioning of the various constituents of the reflector during assembly, similar to FIG. 2 except with regard to the sheet 11, added in the embodiment of FIG. 5, which constitutes the interface between the structure main 6 and the reflecting surface 7, and the gap 8 which is located between the sheet 11 and the reflecting surface 7.
  • the adhesive product 9 is deposited on the face of the reflecting surface 7 opposite the sheet 11. In the figure 5, this product is shown before expansion.
  • FIG. 6 schematically represents the reflector obtained according to the invention after expansion and polymerization of the adhesive.
  • the expanded adhesive 9 has easily penetrated into the sheet 11, ensuring the anchoring of the reflecting surface 7. It may also be recalled that the presence of this sheet 11 regulates the expansion of the adhesive and reduces the stresses possibly introduced by it.

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  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Optical Elements Other Than Lenses (AREA)
  • Aerials With Secondary Devices (AREA)
  • Casting Or Compression Moulding Of Plastics Or The Like (AREA)
  • Lining Or Joining Of Plastics Or The Like (AREA)

Description

La présente invention concerne un procédé de fabrication de réflecteur d'ondes en matières plastiques, ainsi qu'un réflecteur obtenu par ce procédé, un tel réflecteur étant notamment destiné à être utilisé en radar ou en télécommunications.The present invention relates to a process for manufacturing a plastic wave reflector, as well as a reflector obtained by this process, such a reflector being in particular intended for use in radar or in telecommunications.

Il est également connu de réaliser des réflecteurs du type «sandwich» par exemple par le document FR-A-2168 891, qui comporte une première feuille métallique destinée à former le réflecteur, disposée sur un moule, une deuxième feuille destinée à former la face arrière du réflecteur, disposée à une certaine distance de la première feuille, l'espace entre les deux feuilles étant rempli par une matière plastique.It is also known to produce reflectors of the “sandwich” type, for example by document FR-A-2168 891, which comprises a first metal sheet intended to form the reflector, placed on a mold, a second sheet intended to form the face rear of the reflector, arranged at a certain distance from the first sheet, the space between the two sheets being filled with a plastic material.

On connaît également des réflecteurs du type «sandwich» comportant une âme en matériaux nids d'abeilles, recouverte de tissus imprégnés de résines polyesters ou époxydes. En général, ces réflecteurs sont constitués par assemblages successifs des éléments constitutifs définis ci-dessus sur un moule métallique ou en matière plastique, usiné avec une grande précision suivant le profil de la pièce à obtenir. Après durcissement des résines d'imprégnation et de collage, le réflecteur est démoulé.Reflectors of the “sandwich” type are also known comprising a core of honeycomb materials, covered with fabrics impregnated with polyester or epoxy resins. In general, these reflectors are formed by successive assemblies of the constituent elements defined above on a metal or plastic mold, machined with great precision according to the profile of the part to be obtained. After hardening of the impregnation and bonding resins, the reflector is removed from the mold.

Cependant, des essais ont montré qu'une stabilité dimensionnelle satisfaisante, en particulier dans des conditions climatiques sévères, ne peut pas être obtenue sans une opération supplémentaire de polymérisation totale des résines utilisées. Cette polymérisation complète peut être obtenue par un étuvage du réflecteur sur son moule ou sur un conformateur. Cependant, les déformations que ces moules ou conformateurs subissent du fait de la température d'étuvage ne permettent pas d'obtenir un réflecteur d'onde de qualité suffisante pour être utilisé sans inconvénient. Pour qu'après étuvage le réflecteur obtenu présente les qualités requises, il faudrait utiliser des moules réalisés à partir de matières à faible coefficient de dilatation, comme par exemple des alliages fer-nickel spéciaux ou des céramiques, qui entraînent des coûts de matière et de mise en oeuvre très élevés.However, tests have shown that satisfactory dimensional stability, in particular under severe climatic conditions, cannot be obtained without an additional operation of total polymerization of the resins used. This complete polymerization can be obtained by steaming the reflector on its mold or on a shaper. However, the deformations that these molds or conformers undergo due to the oven temperature do not make it possible to obtain a wave reflector of sufficient quality to be used without drawbacks. So that after baking the reflector obtained has the required qualities, it would be necessary to use molds made from materials with a low coefficient of expansion, such as for example special iron-nickel alloys or ceramics, which entail costs of material and very high implementation.

On a cherché à remédier à cet état de chose, en particulier en réalisant d'abord de façon précise ce que l'on appelle la structure principale du réflecteur, puis la face réfléchissante. Cependant la réalisation d'une structure principale à bonne stabilité dimensionnelle requiert un usinage précis, fait après l'étuvage, de façon que la peau réfléchissante soit posée sur une structure principale rigide et précisément aux dimensions requises. Un tel procédé de fabrication, relativement complexe, présente le désagrément qu'il faut recourir à une opération d'usinage précise, quelquefois à deux, pour obtenir une structure principale suffisamment rigide et sans déformation permettant ultérieurement d'avoir un réflecteur de bonne qualité.We sought to remedy this state of affairs, in particular by first carrying out precisely what is called the main structure of the reflector, then the reflecting face. However, the production of a main structure with good dimensional stability requires precise machining, done after baking, so that the reflecting skin is placed on a rigid main structure and precisely to the required dimensions. Such a relatively complex manufacturing process has the inconvenience that it is necessary to have recourse to a precise machining operation, sometimes in pairs, in order to obtain a main structure which is sufficiently rigid and without deformation, making it possible subsequently to have a good quality reflector.

L'objet de l'invention est un procédé de fabrication de réflecteurs d'ondes en matières plastiques associant une stabilité dimensionnelle élevée à une grande précision de forme, qui évite les inconvénients cités, en particulier les usinages nécessaires pour remédier aux défauts constatés après l'étuvage. A cet effet, on réalise la structure principale, on réalise la surface réfléchissante, puis on assemble la structure principale avec la face réfléchissante en encollant la face réfléchissante à l'aide d'un adhésif s'expansant température ambiante, en mettant en position de façon précise la structure principale sans contact sur la peau réfléchissante, l'adhésif s'expansant puis se polymérisant.The object of the invention is a process for manufacturing plastic wave reflectors combining high dimensional stability with high form accuracy, which avoids the drawbacks mentioned, in particular the machining operations necessary to remedy the defects observed after the steaming. For this purpose, the main structure is produced, the reflective surface is produced, then the main structure is assembled with the reflective face by gluing the reflective face using an adhesive which expands at room temperature, by positioning precisely the main structure without contact on the reflecting skin, the adhesive expanding and then polymerizing.

Le procédé selon l'invention est plus précisément défini par la revendication 1.The method according to the invention is more precisely defined by claim 1.

D'autres particularités et résultats de l'invention ressortiront de la description qui suit, à l'aide des figures qui représentent:

  • - les figures 1, 2, 3, les différentes phases de réalisation d'un réflecteur suivant l'invention;
  • - les figures 4, 5 et 6, les différentes phases de réalisation d'un réflecteur suivant une variante de l'invention.
Other features and results of the invention will emerge from the description which follows, with the aid of the figures which represent:
  • - Figures 1, 2, 3, the different stages of production of a reflector according to the invention;
  • - Figures 4, 5 and 6, the different stages of production of a reflector according to a variant of the invention.

Sur ces différentes figures, les mêmes références se rapportent aux mêmes éléments.In these different figures, the same references relate to the same elements.

La figure 1 représente de façon schématique, vue en coupe transversale, une réalisation de la structure principale, répérée 6, d'un réflecteur selon l'invention. La structure principale fait appel pour sa fabrication aux étapes suivantes:

  • - pose sur un moule de précision (non représenté) en plastique ou en métal d'un ou de plusieurs tissus de verre ou carbone ou aramide et imprégnation de ces tissus par une substance susceptible de se polymériser, telle que résine polyester ou époxyde, constituant ainsi une première peau 1;
  • - collage sur cette peau 1 d'une âme 2 en matériau nids d'abeilles, plastique ou métallique, c'est-à-dire que l'âme est constituée d'une pluralité de cellules cylindriques parallèles, les cylindres étant à base polygonale et orientés perpendiculairement à la peau 1;
  • -pose sur l'âme 2 d'un ou de plusieurs tissus de verre, carbone ou aramide, et imprégnation de ces tissus par une substance susceptible de se polymériser, telle que résine, polyester ou époxyde, formant ainsi une deuxième peau 3.
Figure 1 shows schematically, in cross section, an embodiment of the main structure, referenced 6, of a reflector according to the invention. The main structure uses the following stages for its manufacture:
  • - laying on a precision mold (not shown) in plastic or metal of one or more glass or carbon or aramid fabrics and impregnation of these fabrics with a substance liable to polymerize, such as polyester or epoxy resin, constituting thus a first skin 1;
  • - Bonding on this skin 1 of a core 2 made of honeycomb material, plastic or metallic, that is to say that the core consists of a plurality of parallel cylindrical cells, the cylinders being of polygonal base and oriented perpendicular to the skin 1;
  • placed on the core 2 of one or more glass, carbon or aramid fabrics, and impregnation of these fabrics with a substance capable of polymerizing, such as resin, polyester or epoxy, thus forming a second skin 3.

Cet ensemble 6 est durci, sensiblement à température ambiante, puis démoulé et placé sur un simple support où il subit l'opération d'étuvage jusqu'à polymérisation totale.This assembly 6 is hardened, substantially at room temperature, then removed from the mold and placed on a simple support where it undergoes the steaming operation until complete polymerization.

On notera la présence de crans 4 dans l'âme 2, en vis-à-vis de la peau 3, destinés à mettre à l'air libre les nids d'abeilles de l'âme 2, dont la fonction est précisée plus loin.Note the presence of notches 4 in the core 2, facing the skin 3, intended to vent the honeycombs of the core 2, the function of which is specified below. .

On notera également dans la peau 1 la présence de trous 5 utilisés lors de l'opération ultérieure d'assemblage.Note also in the skin 1 the presence of holes 5 used during the subsequent assembly operation.

La figure 2 représente de façon schématique l'opération d'assemblage de la structure principale 6 de la figure 1 avec une surface réfléchissante.Figure 2 schematically shows the assembly operation of the main structure 6 of Figure 1 with a reflective surface.

La surface réfléchissante, repérée 7, est réalisée de la façon suivante:

  • - pose, sur le moule de précision déjà utilisé pour la fabrication de la structure principale (toujours non représentée) d'un ou de plusieurs tissus réfléchissants, par exemple des tissus mixtes verre-métal, des tissus ou nappes de fibres de carbone, des toiles métalliques.
  • - imprégnation des matériaux par une substance susceptible de se polymériser, telle que résine polyester ou époxyde.
  • - application des matériaux imprégnés sur le moule, par exemple par dépression, un film de matière plastique étant déposé sur le matériau imprégné.
  • - polymérisation sensiblement à température ambiante.
The reflecting surface, marked 7, is produced in the following way:
  • - laying, on the precision mold already used for the manufacture of the main structure (still not shown) of one or more reflective fabrics, for example mixed glass-metal fabrics, fabrics or webs of carbon fibers, metal fabrics.
  • - impregnation of the materials with a substance liable to polymerize, such as polyester resin or epoxy.
  • - Application of the impregnated materials on the mold, for example by vacuum, a plastic film being deposited on the impregnated material.
  • - polymerization substantially at room temperature.

Au moment où se fait l'assemblage, on a donc la structure principale 6 telle que représentée figure 1, après étuvage c'est-à-dire avec des défauts, ou plus exactement des différences dans son profil (non représentées) dues au post-retrait qui s'est produit lors de son étuvage et, disposée en regard de la peau 1, la surface réfléchissante 7 avec un intervalle prédéfini 8 séparant les deux surfaces en regard respectivement de la peau 1 et de la surface réfléchissante 7; dans cet intervalle 8, on dispose un produit adhésif 9 capable d'expansion. Sur la figure 2, ce produit adhésif est représenté avant expansion.At the time of assembly, there is therefore the main structure 6 as shown in FIG. 1, after baking, that is to say with defects, or more exactly differences in its profile (not shown) due to the post shrinkage which occurred during its steaming and, placed facing the skin 1, the reflecting surface 7 with a predefined interval 8 separating the two facing surfaces respectively of the skin 1 and the reflecting surface 7; in this interval 8, there is an adhesive product 9 capable of expansion. In Figure 2, this adhesive product is shown before expansion.

L'assemblage de la structure principale avec la surface réfléchissante se déroule de la façon suivante:

  • - on encolle la face interne de la surface réfléchissante 7 avec un produit adhésif 9 s'ex- pansant à température ambiante tel qu'une colle (Araldite, marque déposée, par exemple) à laquelle on ajoute un agent susceptible de former une structure mouvante; un tel produit est par exemple commercialisé par la Société CIBA GEIGY sous la référence FW 650.
  • - on met en position de façon précise la structure principale sans contact sur la peau réfléchissante, par exemple à l'aide d'un outillage à base d'entretoises, c'est-à-dire qu'on ménage un intervalle 8 constant entre les deux surfaces en regard, la structure principale étant placée par rapport à la surface réfléchissante enduite de façon telle qu'on soit à la limite d'un affleurement de la face concernée de la peau 1 avec le produit adhésif 9 en un point seulement de l'adhésif 9.
  • - les éléments précédents étant ainsi mis en place, le produit adhésif 9 s'expanse, compensant ainsi les différences de profil de la structure principale qui se sont produites lors du post-retrait à l'étuvage, et permettant d'éviter l'usinage qui était nécessaire selon les techniques connues; l'expansion du produit adhésif utilisé comble ainsi y intervalle 8 entre la première peau 1 de la structure principale et la peau réfléchissante 7, cette expansion est rendue possible par la présence des crans 4 qui mettent à l'air libre les nids d'abeilles de l'âme 2 où s'effectue l'expansion.
The assembly of the main structure with the reflective surface takes place as follows:
  • - the internal surface of the reflecting surface 7 is glued with an adhesive product 9 which expands at room temperature such as an adhesive (Araldite, registered trademark, for example) to which an agent capable of forming a moving structure is added ; such a product is for example marketed by the company CIBA GEIGY under the reference FW 650.
  • - The main structure is positioned precisely without contact on the reflective skin, for example using a tool based on spacers, that is to say that a constant interval 8 is maintained between the two facing surfaces, the main structure being placed relative to the coated reflective surface in such a way that it is at the limit of a leveling of the concerned face of the skin 1 with the adhesive product 9 at only one point of adhesive 9.
  • - the above elements being thus put in place, the adhesive product 9 expands, thus compensating for the differences in profile of the main structure which occurred during post-shrinkage during baking, and making it possible to avoid machining which was necessary according to known techniques; the expansion of the adhesive product used thus fills the gap 8 between the first skin 1 of the main structure and the reflective skin 7, this expansion is made possible by the presence of the notches 4 which open the honeycombs to the open air of the core 2 where the expansion takes place.

La figure 3 montre de façon schématique le produit fini, c'est-à-dire le réflecteur obtenu par application du procédé suivant l'invention. On constate que l'adhésif 9 expansé occupe tout l'intervalle 8 et qu'il a pénétré par les trous 5 prévus dans la première peau 1 de la structure principale 6, pour créer des points d'acrage 10 de la surface 7 dans l'âme 2 de la structure principale 6.Figure 3 shows schematically the finished product, that is to say the reflector obtained by applying the method according to the invention. It is noted that the expanded adhesive 9 occupies the entire interval 8 and that it has penetrated through the holes 5 provided in the first skin 1 of the main structure 6, to create anchor points 10 of the surface 7 in the core 2 of the main structure 6.

L'adhésif utilisé, qui s'expanse lors de la mise en oeuvre, sans être aussi liquide qu'une colle normale, peut toutefois présenter un degré de fluidité suffisant avant expansion pour risquer de ne pas tenir en place lorsque la surface de la surface réfléchissante sur laquelle il est étendu présente un galbe important.The adhesive used, which expands during processing, without being as liquid as a normal adhesive, may however have a sufficient degree of fluidity before expansion to risk not remaining in place when the surface of the surface reflective on which it is extended has a significant curve.

Pour régulariser l'expansion de l'adhésif utilisé et éviter qu'il ne coule, plus particulièrement dans le cas de moules très galbés, on prévoit, suivant une variante de l'invention, une opération consistant, lors de la réalisation de la structure principale, à la mise en place sur le moule de précision qui est utilisé pour fabriquer, une feuille mince de nids d'abeilles plastique ou métallique sur laquelle, ensuite, on exécute l'opération de pose et de collage de la première peau, opération qui était précédemment faite la première.To regularize the expansion of the adhesive used and prevent it from flowing, more particularly in the case of highly curved molds, provision is made, according to a variant of the invention, for a consistent operation, during the production of the structure. main, when placing on the precision mold which is used to manufacture, a thin sheet of plastic or metallic honeycombs on which, then, the operation of laying and gluing the first skin is carried out, operation which was previously made the first.

Les figures 4, 5 et 6 représentent de façon schématique les différentes étapes de réalisation d'un réflecteur suivant cette variante du procédé selon l'invention.Figures 4, 5 and 6 schematically show the different stages of producing a reflector according to this variant of the method according to the invention.

La figure 4 représente la structure principale réalisée conformément à la variante du procédé suivant l'invention.FIG. 4 represents the main structure produced in accordance with the variant of the method according to the invention.

Cette structure comprend une feuille mince 11 de nids d'abeilles, plastique ou métallique, déposée sur un moule de précision (non représenté), collée à la première peau 1, l'âme 2 en matériau nids d'abeilles collée sur la peau 1 et la deuxième peau 3 collée sur l'âme 2. Après la pose des différents composants énumérés ci-dessus, l'ensemble est durci à température ambiante puis démoulé et placé ensuite sur un support simple où est effectuée l'opération d'étuvage aboutissant à la polymérisation totale.This structure comprises a thin sheet 11 of honeycombs, plastic or metallic, deposited on a precision mold (not shown), glued to the first skin 1, the core 2 of honeycomb material glued to the skin 1 and the second skin 3 bonded to the core 2. After the installation of the various components listed above, the assembly is hardened at ambient temperature then unmolded and then placed on a simple support where the steaming operation is carried out, resulting to total polymerization.

On notera dans cet ensemble la présence des crans 4 dans la feuille 11 et non plus dans l'âme 2 comme précédemment.Note in this set the presence of the notches 4 in the sheet 11 and no longer in the core 2 as before.

La structure principale étant ainsi réalisée, on procède à la réalisation de la surface réfléchissante 7 de la façon qui a été décrite précédemment. L'assemblage de la structure avec la surface réfléchissante est alors exécuté.The main structure being thus produced, the reflective surface 7 is produced in the manner which has been described previously. The assembly of the structure with the reflecting surface is then carried out.

La figure 5 représente la mise en place des différents constituants du réflecteur lors de l'assemblage, semblable à la figure 2 sauf en ce qui concerne la feuille 11, ajoutée dans la réalisation de la figure 5, qui constitue l'interface entre la structure principale 6 et la surface réfléchissante 7, et l'intervalle 8 qui se trouve entre la feuille 11 et la surface réfléchissante 7. Le produit adhésif 9 est déposé sur la face de la surface réfléchissante 7 en regard de la feuille 11. Sur la figure 5, ce produit est montré avant expansion.FIG. 5 represents the positioning of the various constituents of the reflector during assembly, similar to FIG. 2 except with regard to the sheet 11, added in the embodiment of FIG. 5, which constitutes the interface between the structure main 6 and the reflecting surface 7, and the gap 8 which is located between the sheet 11 and the reflecting surface 7. The adhesive product 9 is deposited on the face of the reflecting surface 7 opposite the sheet 11. In the figure 5, this product is shown before expansion.

La figure 6 représente de façon schématique le réflecteur obtrenu suivant l'invention après expansion et polymérisation de l'adhésif.FIG. 6 schematically represents the reflector obtained according to the invention after expansion and polymerization of the adhesive.

On pourra noter que l'adhésif 9 expansé a pénétré facilement dans la feuille 11, assurant l'ancrage de la surface réfléchissante 7. On peut également rappeler que la présence de cette feuille 11 régularise l'expansion de l'adhésif et réduit les contraintes éventuellement introduites par celui-ci.It will be noted that the expanded adhesive 9 has easily penetrated into the sheet 11, ensuring the anchoring of the reflecting surface 7. It may also be recalled that the presence of this sheet 11 regulates the expansion of the adhesive and reduces the stresses possibly introduced by it.

Claims (6)

1. Method of producing a wave reflector from plastics material, comprising a step of producing a main structure on a mold having the desired shape of the reflector, the main structure comprising a honeycomb core covered with sheets on both of its opposed faces; the method being characterized by the fact that the step of producing the main structure comprises the following substeps:
- positioning at least one tissue on the mold and impregnating the tissue with a substance susceptible of polymerization, thus forming a first sheet;
- affixing a honeycomb core on the first sheet;
- positioning at least one tissue on the core and impregnating the sheet with a substance susceptible of polymerization, thus forming a second sheet;
- curing the unit;
- separating the unit from the mold;
- treating the unit in an oven; characterized in that the method further comprises the following steps:
- forming a reflecting surface on the mold;
- depositing an adhesive material susceptible of expansion on the reflecting surface;
-assembling the main structure with the reflecting surface on the side of the adhesive material, an interval remaining between the mutually facing sides of these two elements;
-expanding the adhesive material whereby the reflecting surface is rigidly affixed to the main structure.
2. Method according to claim 1, characterized by the fact that the step of forming the reflecting surface comprises the following steps:
- positioning at least one reflecting tissue on the mold;
- impregnating this tissue with a substance susceptible of polymerization;
- applying the impregnated tissue on the mold by depression;
- polymerization substantially at the environment temperature.
3. Method according to any of the preceding claims, characterized by the fact that the step of assembling the main structure with the reflecting surface is performed while an interval is maintained in such a manner that the adhesive material contacts the main structure on at least one point.
4. Method according to any of the preceding claims, characterized by the fact that holes (5) are located in the first sheet (1) of the main structure wherethrough the adhesive material (9) expands, thus forming anchoring points of the reflecting surface (7) in the core (2) of the structure.
5. Method according to claim 1, characterized by the fact that during the first step an additional sheet of honeycomb material is interposed between the mold and the tissue, the assembly of the reflecting surface being performed with the main structure on the side of the additional sheet, and the adhesive material penetrating into the additional sheet when it is expanded, thus performing a rigid connection between the reflecting surface and the main structure.
6. Wave reflector of plastics material, obtained by the method according to any of the preceding claims, characterized by the fact that the main structure is embodied by means of at least two tissues of glass, carbon or aramide, the tissues being impregnated with a polyester or epoxy resin and being located on both sides of a core of honeycomb plastics or metallic material.
EP19830401887 1982-09-28 1983-09-27 Process for the manufacture of a plastic wave reflector, and reflector made by this method Expired EP0105007B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8216299 1982-09-28
FR8216299A FR2533494A1 (en) 1982-09-28 1982-09-28 PROCESS FOR MANUFACTURING REFLECTORS IN PLASTIC MATERIALS

Publications (2)

Publication Number Publication Date
EP0105007A1 EP0105007A1 (en) 1984-04-04
EP0105007B1 true EP0105007B1 (en) 1987-11-19

Family

ID=9277806

Family Applications (1)

Application Number Title Priority Date Filing Date
EP19830401887 Expired EP0105007B1 (en) 1982-09-28 1983-09-27 Process for the manufacture of a plastic wave reflector, and reflector made by this method

Country Status (3)

Country Link
EP (1) EP0105007B1 (en)
DE (1) DE3374630D1 (en)
FR (1) FR2533494A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104779046A (en) * 2015-04-28 2015-07-15 北京瑞奇恩互感器设备有限公司 Anti-noise open-close type current transformer

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0196734A3 (en) * 1985-03-28 1988-08-03 Satellite Technology Services, Inc. Cassegrain antenna for tvro application

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1359167A (en) * 1962-02-05 1964-04-24 Kennedy Antenna Division Of El Improvement in parabolic reflectors
GB1329981A (en) * 1969-12-08 1973-09-12 Goodyear Tire & Rubber Skin covered foam article and method of preparation
GB1354352A (en) * 1970-06-05 1974-06-05 Monostruct Corp Ltd Moulded cored structural component and method of producing same
FR2165739A1 (en) * 1971-12-28 1973-08-10 Labo Cent Telecommunicat Radar reflector bodies - comprising a rigid (polyurethane) foam dish with polyester impregnated glass cloth covers
FR2168891B3 (en) * 1972-01-25 1975-02-07 Filoche Pierre
NL179527C (en) * 1977-05-20 1986-09-16 Philips Nv METHOD AND APPARATUS FOR MANUFACTURING A REFLECTOR WITH A PLASTIC SUPPORT BODY
JPS55117304A (en) * 1979-03-01 1980-09-09 Mitsubishi Electric Corp Curved surface panel
IL63639A0 (en) * 1980-09-05 1981-11-30 Stanford Res Inst Int Radiation reflector arrangement

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN104779046A (en) * 2015-04-28 2015-07-15 北京瑞奇恩互感器设备有限公司 Anti-noise open-close type current transformer

Also Published As

Publication number Publication date
DE3374630D1 (en) 1987-12-23
FR2533494B1 (en) 1985-05-03
EP0105007A1 (en) 1984-04-04
FR2533494A1 (en) 1984-03-30

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