A SCAFFOLDING SAFETY BARRIER

A SCAFFOLDING SAFETY BARRIER

FIELD OF THE INVENTION

This invention relates to safety equipment in particular but not exclusively to a scaffolding safety barrier for use on building or construction sites.

BACKGROUND OF THE INVENTIO

The need to provide safety for workers in the construction industry is well established. This is especially so where workers work on scaffolding in elevated positions high above the ground, in certain countries, scaffolding must be accompanied by safety barriers such as vertical nets or screens spanning across the scaffolding members to prevent workers, or debris from falling to the ground. Prior art screens and barriers are usually robust and of a heavyweight construction to ensure they are of sufficient tensile strength to prevent failing when impacted by a force or load. In a typical prior art example, the barrier comprises a heavy duty plastic mesh having a skeletal grid welded or bonded to the mesh. This makes the barrier difficult to fold or roll, heavy to carry resulting in possible injuries claimable pursuant to work, health and safety legislation. These types of barriers are also prone to delamiiiating Of the grid from the mesh resulting in non degradable waste ending u in landfill.

Furthermore, the types of mesh currently on the market for use as safety barriers comprise metal components. Thereby the process for preparing the mesh may require a two step process. The steps comprise preparation of metal mesh (eg chain wire) followed by incorporation onto a shade doth (e nylon, or similar).

OBJECT OF THE INVENTIO ft is the object of the invention to provide a scaffolding safety barrier which alleviates or ameliorates the problems of the prior art or to provide the public with a useful choice.

STATEMENT OF INVENTION

In one aspect therefore the invention resides in a safety barrier for scaffolding comprising in combination;

a woven mesh for attaching to scaffolding; the warp and weft of the mesh fibres comprising woven zones of different tensile strengths in at least two directions;

the zones cooperating in concert to differentially dissipate and absorb elastic recoil of the mesh when impacted by a force or a load thereby substantially dampening rebound of the barrier.

Preferably, the different tensile strengths are achieved by increasing or decreasing the number of fibres woven per unit area of mesh thereby controlling, the behaviour of elastic rebound according to a pattern created by the zones, in a preferred example, the zones comprise vertical and horizontal bands forming a grid pattern. fn the alternative, the zones comprise a pattern of repeated polygonal shapes other than squares or rectangles including circles, hexagons or bands running obliquely to the horizontal and/ or vertical axes of the barrier.

Preferably, the mesh is woven from fibres of high density polypropylene (HOPE) with a fire re tarda nt rating of between IS to 65,

Preferably, the safety barrier is used in building construction sites.

Preferably, the safety barrier further comprises eyelets.

Preferably, the weight of the barrier is less than 12 kg.

fn another aspect, the present invention provides a method of providing safety for a construction site comprising placing the barrier according to claim 1 around at least part of the periphery of the site.

Preferably, the barrier is used for scaffolding, temporary fencing, cargo barriers; and as a soil sediment prevention screen, excavation perimeter safety net, roadworks net, dust and debris net, and the like.

Prefera ly, the the fire rating is 25.

In another aspect, the present invention provides a method of forming a mesh according to claim 1 comprising:

(tj preparing warp and weft of the mesh fibres comprising woven zones of different tensile strengths in at least two directions;

the zones cooperating in concert to differentially dissipate and absorb elastic recoil of the mesh when impacted by a force or a load thereby substantially dampening rebound of the barrier; (ti) increasing or decreasing the number of fibres woven per unit area of mesh thereby controlling the behaviour of elastic rebound according to a patter created by the zones; and (tii) utilizing fibres of high density polypropylene (HOPE),

BRIEF DESCRIPTION OF THE DRAWINGS

In order for the invention to be better understood reference will now be made to the accompanying drawings, wherein:

Figure 1 shows a preferred barrier of the invention.

Figu e 2 shows magnified view of mesh of the barrier of Figure 1.

Figu re 3 shows the eyelets as an embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Referrin now to Figure 1 there is shown a preferred example of the invention. In this embodiment the safety barrier 10 for scaffolding is a woven mesh for attach ing to scaffolding members 11, 13, 15 by means of locking dips or heavy duty cable ties passing through eyelets 12, 14, 16, IS. The woven zones comprise vertical 20 and horizontal 22 bands forming a grid pattern. In the alternative, the zones may comprise a pattern of repeated polygonal shapes 20 other than squares or rectangles such as circles, hexagons or bands running obliquely to the horizontal and/ or vertical axes of the barrier.

Figure 2 shows a magnified view of the mesh 24 of the barrier 10 of Figure 1. The warp and weft of the mesh fibres comprise woven zones 26,28,30,32 of different tensile strengths in at least two directions. The different tensi le strengths are achieved by increasing or decreasing the number of fibres woven per unit area of mesh thereby controlling the behaviour of elastic rebound of the barrier according to the pattern created by the woven zones. The mesh is woven from fibres of high density polypropylene (HOPE) with a fire retardant rating of between 15 to 6S.. in the alternative, the mesh may be woven from a combination of fibres and can include a matri of metal, textile and/or HOPE fibres.

In use, the safety barrier according to the present invention includes applications such as for building construction sites a nd the like. The safety barrier may be used to surround at least part, of the periphery of the construction site, for example, around scaffolds at a building site. Other applications include, and are not limited to use of safety barriers for temporary fencing, cargo barriers, soil sediment prevention screen, excavation perimeter safety net, roadworks net, dust and debris net, and the like.

The Basic Process of Plastic Extrusion

The plastic extrusion process begins with the placement of raw resi n into the extruder's hopper, ff the resin lacks additives necessary for the pa rticular application (such as UV inhibitors, antioxidants, or colorants), then they are then added to the hopper. Once in place, the resin is typically gravity-fed through the feed throat of the hopper down into the extruder's barrel. Withi n the barrei is a long, rotating screw that feeds the resin forward in the barrel towards the die.

As the resin moves along withi n the barrel, it is subjected to extremely high temperatures u ntil it starts to melt. Depending on the type of thermoplastic, barrel temperatures can range between 400 and 530 degrees Fahrenheit. Most extruder's have a barrel that gradually increases in heat from the loading end to the feed pipe to enable gradual melting and minimize the possibility of lastic degradation.

Once the molten material reaches the end of the barrel, it is forced through a screen pack and fed into the feed pipe that leads to the die. The screen, reinforced by a breaker plate due to high pressures in the barrel, serves to remove contaminants that may be present in the molten material. The porosity of the screen, number of screens, and other factors can be manipulated until uniform melting occurs as a result of the right amount of back pressure.

Once in the feed pipe, the molten material is fed into the die cavity, where it cools and hardens. To expedite the cooling process, the newly formed material receives a sealed water bath.

Temperature Maintenance

Maintaining the correc temperature level and melting rate of the extrusions. Optimal temperature maximises uniform fluidity of the components, and minimizes the possibility for stress and warping of the final product. Variables such as pressure and friction that build up in the barrel of the extruder mean that temperatures are not remaining constant. Heaters must be monitored, lowered, raised, or shutoff as necessary to maintain constant heat within the extruder - cooling fa ns and east-jn heater jackets can also help mai ntai.n proper extrusion temperature.

As the HOPE i cooled it is attached to several spindles and transferred to bobbins which can hold up to l,000mts of yarn. Ready then to be loaded to knitting machines that have been modified to produce the designed Mesh, Eyeletting is carried out after the knitting process.

Advantages The safety barriers according to the present invention demonstrate superior properties in relation to fire retard ant rating and uv resistant rating compared to comparable products on the market.

The safety barrier is convenient and easy to hand le and transport due to its lightweight. For example, a safety barrier of roll size of 15m x 1.9m weighs about 11 kg.

Other roll sizes include, for example, 10m x 1.9m and 10m x Im.

The advantages of the safety barrier according to the present invention include the following: fi) providing safety barriers without any metal components, hereby eliminating a process ste in the preparation of the mesh;

(ii) providing tight weight material, eg up to 50% lighter than comparable products currently on the market;

(til) eliminating use of metal wires in barriers thereby decreasing potential injury in workplace and reducing cutting of mesh;

(tv) durability and easy to roll, tra nsport, handle and store;

(v) preparing ba m^'ers without any hazardous or toxic components or chemicals;

(vi) providing barriers conforming to national health and safety regu lations; (vit) achieving fire retardant properties of superior industry rating ; increasing the strength of the barrier by knitting structural arrangement and formation;

(ix) recycling and reusable properties of barriers;

(x) longevity; barrier mesh does not easily disintegrate or degenerate under norma! use;

(xi) demonstrating superior uv resistant rating..

It will of course be realised that while the foregoing has been given by way of illustrative example of this invention, all such and other modifieations and variations thereto as would be apparent to persons skilled in the art are deemed to fall within the broad scope and ambit of this invention as is herein set forth.

In the specification the terms "comprising" and "containing" shall be understood to have a broad meaning similar to the term "including" and will be understood to imply the inclusion of a stated integer or step or group of integers Or steps but not the exclusion of any other integer or step or group of integers or steps. This definition also applies to variations on the terms "comprising" and "containing" such as "comprise", "comprises", "contain" and "contains".