FR2779162A1 - Protection sleeve for road crash barrier posts - Google Patents

Abstract

The crash barrier post protection sleeve is constituted from an elliptical shaped flexible, resilient thick sheet (1) edged on two sides by hook rolls (2) able to be hooked on the post returns (3). In the event of collision the resilient sheath causes a progressive reduction of the deformation space (4) before contact with the post edge (5).

Description

- 1 -

DESCRIPTION.

  The present invention relates to a protective sleeve for

  metal safety lateral rail support posts

third.

  These posts, placed every 2 meters, in fact constitute a hazard.

  serious management in the event of an accident, especially in the event of driver ejection or

  passenger sliding on the road (frequent case for motorcycles-

  your). Taking into account the number of existing posts and already in place without protection, the objectives of the product must be in priority: - a fast and easy installation without any need for intervention on the post itself, - a minimum cost,

  - sufficient capacity for progressive absorption of kinetic energy

than a body hitting the post.

  The product according to the invention makes it possible to meet these three objectives.

  tifs. It is in fact in the form of a section of thick flexible and elastic sheet in the form of an elliptical arc terminated on 2 lateral edges.

  opposite by 2 hook-shaped beads which can be anchored in the

  profiling towers for standard metal support posts

metallic sieres.

  Figure 1 illustrates the shape of the cross section of the section

  flexible sheet and a slide post.

  We can see in 1 the flexible and elastic sheet of thick

  aunt in 2 the end fangs and in 3 the profiling returns

a standard post.

  The length of the section along the beaded edges corresponds to

  the height of the post to be protected between the ground and the lower edge of the slide

  metal case. This height is generally normalized.

  The sleeve is put in place by placing one of the 2 bour-

  hook snap hooks on one of the post profiling returns and then fold the sheet to bring the other hook snap hook

  on the other return of the post profiling.

  The result of the operation is illustrated in Figure 2. The sleeve

  is then securely attached to the post by its elasticity

-2 -

  pre annoyed by the 2 hooks by bead-hook.

  This figure 2 highlights the accentuated curvature of the flexible sheet guaranteeing the resistance of the attachment of the bead-hooks 2

  in the profiling returns 3 of the standard support posts.

  This accentuated curvature also ensures a possible deformation space 4 of the flexible sheet before contact with a rigid edge 5 of the

  post following an impact on the sleeve.

  The width of the sleeve between the 2 beads, the thickness of the sheet and the modulus of elasticity of the material constituting the product are determined so that the energy necessary to deform the sleeve in place and bring it into contact with an edge of the pole, absorbs a significant amount of the kinetic and potential energy of the usual body striking the pole. This deformation is illustrated by the

figure 3.

  We distinguish in 5 the close contact, of the deformed elastic sheet.

  sleeve of the sleeve with the rigid edge 5 of the post. This contact ends

the protective phase of the sleeve.

  It is therefore essential that the modulus of elasticity of the base material

  of the sleeve is optimized and slightly sensitive to variations in temperature

  temperatures likely to occur on a road (from - 20 c to + 45 c).

  The "thickness-width" couple can then be determined from

  of tests carried out at medium temperature (12 c).

  To meet the objective of minimum cost, the product has been designed to be achievable by continuous extrusion-shaping of a plastic material having the thermal stability of modulus of elasticity.

  cited above, followed by cutting into sections to the requested length.

  Always for the same purpose the basic material could be a plas-

  tick from recycling and treatment with sufficient elasticity

  firmly stable and reliable and having the mechanical and

required thermal.

  By way of nonlimiting example, the sleeve may be produced from plasticized PVC originating from recycling after treatment of flexible sheaths of electric cables or the like, having a thickness of 7 mm,

  35. have a width between beads of 75 cm and a height of 40 cm.

-3 -

Claims (3)

  1) Protective sleeve for metal slide support posts   ques road safety vis-à-vis body striking these poles after sliding on the road; this sleeve is characterized by the use of a thick sheet 1, of flexible elastic material and sufficiently thermostable, bordered on 2 edges by bead-hooks 2 allowing a fast and resistant attachment on the profiling returns 3 of the standard posts of slides ensuring, after hanging, a sufficient possible deformation space 4 between the flexible sheet and an edge of the post metallic 5.   2) Sleeve according to claim 1 characterized in that its produc-   tion can be ensured continuously by extrusion-shaping of an "ad hoc" plastic material followed by cutting into sections at length requested.   3) Sleeve according to claim 1 or 2 characterized in that the plastic material will be a recycled material possibly reprocessed having the necessary mechanical and thermal characteristics.