FR2503858A2 - Archery target with intermediate polyethylene foam layer - to reduce costs compared with a polyurethane foam core - Google Patents

Abstract

The parent patent described an archery target constructed in layers for progressive resistance to penetration by an arrow, where the structure had a layer 40-150 mm thick of polyurethane foam of apparent density 80-200 kg/m3 incorporated between a rigid (wooden) backboard a surface layer 30-70 mm thick made of expanded polyethylene of apparent density 20-80 kg.m3. This addn. substitutes for the polyurethane foam a further layer of expanded polyethylene of apparent density 100-180 kg/m3. This provides a structure which is just as effective but cheaper because of reduced material costs and content.

Description

 The present invention relates to the field of devices serving as supports and targets for projectiles. It especially relates to improvements to main patent application No. 78.28442, relating to a target for archery.

 We have described in the main patent a target constituted essentially by a complex structure of two thermoplastic foams of different characteristics whose penetration resistance increases from the outside of the target to the rigid support or back retaining this structure.

 More specifically, the target included, from the front part receiving the first impact of the arrows to the rear: a first layer of polyethylene foam with a density of 20 to 80 kg / m3 and a thickness of 30 to 70 mm, in a single block or in several sheets associated with each other; a second layer, playing the role of brake for the arrows, constituted by a polyurethane foam of density 80 to 200 kg / m3 and thickness 40 to 150 mm; and a rigid support on the back of the second layer.

 According to an advantageous embodiment, the polyurethane foam was based on polyether-polyester and was produced by agglomeration of foam waste so as to obtain a reduction in the costs of achieving the target.

 It has now been found that it is possible to further reduce these costs and improve the results by replacing the polyurethane foam with a polyethylene foam with a density of 100 to 180 kg / m 3 obtained from waste foam, for example by hot agglomeration of such waste without the intervention of a binder.

 Such closed cell foam also has the advantage of greater resistance to compression due to the force of penetration of the boom, than in the case of polyether-polyester foam.

It is thus possible to adopt relatively modest thicknesses for this second layer of foam in the target of the invention, for example of the order of 40 to 100 mm.

The production of the improved target is done according to the indications already given in the main patent, namely fixing of the foam on a rigid support, for example wood or other material, and protection of the periphery of the target by a rubber belt
compact or the like. Advantageously, the central part of the foam
is cut into a cone shape to obtain a removable area that is easy to
replace during heavy use of the target.

Claims (1)

 CLAIM  Target for archery according to the main patent, of the type constituted by at least two layers of foams of different density in thermoplastic materials including a first layer of polyethylene foam of density 20 to 80 kg / m3 and thickness 30 to 70 mm, these layers being fixed on a rigid support and surrounded by a circumference of compact rubber or the like, the target being characterized in that the second layer is constituted by a polyethylene foam of density 100 to 180 kg / m3 and thickness 40 to 100mm, obtained by hot agglomeration of waste of such foam.