Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F41—WEAPONS
  • F41H—ARMOUR; ARMOURED TURRETS; ARMOURED OR ARMED VEHICLES; MEANS OF ATTACK OR DEFENCE, e.g. CAMOUFLAGE, IN GENERAL
  • F41H5/00—Armour; Armour plates
  • F41H5/013—Mounting or securing armour plates
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F41—WEAPONS
  • F41H—ARMOUR; ARMOURED TURRETS; ARMOURED OR ARMED VEHICLES; MEANS OF ATTACK OR DEFENCE, e.g. CAMOUFLAGE, IN GENERAL
  • F41H5/00—Armour; Armour plates
  • F41H5/02—Plate construction
  • F41H5/04—Plate construction composed of more than one layer
  • F41H5/0442—Layered armour containing metal
  • F41H5/045—Layered armour containing metal all the layers being metal layers

Definitions

• the present invention relates to a sandwich structural element making it possible to protect equipment against external aggressions and in particular the impacts of projectiles.
• This type of vehicle generally includes a survival cell made up of an assembly of welded steel sheets, covered on the inside of the cell by internal plates in a material such as aluminum.
• an aluminum plate tends to fragment when it undergoes a shock wave, which in some cases results in the projection of shards.
• a protective layer which generally consists of plates of composite material.
• Patent DE 197 40 103 describes a bottom shielding of a vehicle body, in particular against mines, composed of an outer layer of light metal, and an inner layer of shielding steel.
• the layer of light metal has ribs on its face opposite the internal layer which are applied against the internal layer so that the external layer is kept at a distance from the internal layer. It turns out that these ribs make the outer layer completely rigid and therefore impossible to conform to protect the curved surfaces of a vehicle.
• these ribs require a specific manufacture of the outer layer requiring special molds. This therefore also results in risks of difficulty in supply.
• the patent FR 865 964 describes a shield formed by two layers kept spaced from one another by springs. This structure is not very effective because it does not allow to benefit from a beam effect which appears when the external plate is rigidly fixed on the internal layer.
• the present invention aims to eliminate these drawbacks. This objective is achieved by the provision of a sandwich structure ... (here will be copied for legal reasons the claims)
• Figure 1 schematically shows a section of the sandwich structure according to the present invention
• FIGS. 2 to 4 show in section other variants according to the invention of the sandwich structure shown in FIG. 1.
• Protection against projectile impacts from weakly protected vehicles is in principle placed inside the vehicle body. Contrary to this principle, the protective elements are placed according to the invention, outside the vehicle body.
• the vehicle body generally produced by an assembly of steel sheets 1, that is to say a material with very high hardness, is covered on the outside by plates of protection 2 in one very ductile material, such as aluminum.
• the arrow 6 represents the direction of movement of a possible projectile.
• the two layers 1, 2 of the sandwich structure are kept apart from one another, by mechanically fixing the protective plates 2 at a distance from the body 1.
• the distance between the two layers is determined according to the nature of the projectiles to be stopped.
• spacers 7 which are for example welded to the body 1.
• these spacers are for example drilled by a thread to receive screws 5 for fixing the plates of protection.
• the steel sheet plates 1 constituting the body have a thickness of the order of a few millimeters.
• the aluminum protection plates 2 have a thickness of the order of 10 mm or more, depending on the type of projectile to be stopped, and the spacing of these two layers is of the order of one to several tens of millimeters, also depending on the type of projectile to be stopped.
• the assembly undergoes differential expansion during temperature changes. At least part of the holes made for the passage of the screws 5, preferably in the protective plates 2, are therefore oblong.
• the body includes angles 8 which are welded for example by their edge, preferably on the edges of the sheet metal plates 1 constituting the body.
• These angles 8 each include a threaded hole provided for receiving a screw 9 for fixing a protection plate 2.
• These angles make it possible to ensure electrical continuity between the plates 1 of the bodywork and the protection plates 2, for the purposes suppression. They are preferably flexible to allow differential expansions.
• connection between the two layers 1, 2 of the structure is also preferably elastic to allow differential expansions.
• an elastic layer 10 is interposed between the spacer 7 'and the protective plate 2 ( Figure 2).
• This elastic layer also makes it possible to dampen the vibrations generated by projectile impact and ensure isolation of the galvanic couple, while allowing a wider mounting tolerance.
• the spacers 13 have a tabular shape whose central bore is fully threaded, the two layers 1, 2 being drilled to receive screws 5 ', 11 which come screw on each side of the spacer in the central hole.
• the spacers 14 can also have a tabular shape, the two layers 1, 2 being drilled to receive a single screw 5 "passing successively through one of the two layers, the spacer, then the other layer, to be screwed into a nut 12.
• the hole passing through the spacers 14 is tapped so as to be able to fix them on the bodywork before mounting the protection plate 2.
• the sandwich structure described above makes it very surprisingly possible to obtain significantly better protection than when the protection plates 2 are arranged inside the bodywork, and in particular a significantly higher protection-to-mass ratio.
• the first ductile barrier (aluminum protection plate 2) fixed at a distance from the body makes it possible to obtain a beam effect which absorbs part of the kinetic energy of the projectile, while the second barrier (the plates of sheet 1 in body steel) with very high hardness stops the projectile which has lost part of its energy.
• the protection plates 2 can cover the entire body of the vehicle, which makes it possible to obtain a high degree of homogeneity of the protection.
• the sandwich structure according to the invention has a significantly reduced cost of implementation compared to the solutions of the prior art, since it is no longer necessary to provide splash protection plates, the body playing this role.
• the installation of the protective plates 2 is greatly simplified, since these plates can be installed without having to dismantle any equipment. As a result, an armored vehicle that has been impacted can be repaired much more quickly with a simple exchange of damaged protection plates, which are mounted outside the vehicle, resulting in greater operational availability of the vehicles thus protected.
• the invention also makes it possible to considerably simplify the supply of protective elements since the aluminum protective plates are simple plates without any particular machining and having a constant thickness. They can therefore be obtained from a larger number of manufacturers than the protection plates of the prior art which have a specific shape adapted to a type of vehicle.
• the protective plates can also be easily curved, for example to be adapted to the shapes of a vehicle body.

Landscapes

• Engineering & Computer Science (AREA)
• General Engineering & Computer Science (AREA)
• Ceramic Engineering (AREA)
• Aiming, Guidance, Guns With A Light Source, Armor, Camouflage, And Targets (AREA)
• Laminated Bodies (AREA)
• Body Structure For Vehicles (AREA)

Applications Claiming Priority (5)

Publications (1)

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Family Applications (1)

Country Status (5)

Families Citing this family (5)

Citations (1)

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• 2003
  • 2003-07-21 WO PCT/FR2003/002305 patent/WO2004011871A1/fr not_active Application Discontinuation
  • 2003-07-21 US US10/522,075 patent/US20050252113A1/en not_active Abandoned
  • 2003-07-21 AU AU2003267527A patent/AU2003267527A1/en not_active Abandoned
  • 2003-07-21 EP EP03748219A patent/EP1523648A1/de not_active Withdrawn
• 2005
  • 2005-01-11 IL IL166240A patent/IL166240A/en not_active IP Right Cessation

Patent Citations (1)

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