GB2522243A

GB2522243A - A fall arrest unit

Info

Publication number: GB2522243A
Application number: GB1400870.0A
Authority: GB
Inventors: Julie Ann Boon; Christopher George Price
Original assignee: Forest Safety Products Ltd
Current assignee: Forest Safety Products Ltd
Priority date: 2014-01-20
Filing date: 2014-01-20
Publication date: 2015-07-22
Anticipated expiration: 2034-01-20
Also published as: GB2522243B; GB201400870D0

Abstract

A fall arrest unit 10 for use in military, aviation and other extreme environments, the unit 10 comprising an outer casing 12 and an inner cushioning means 24 housing loose-fill, impact absorbing material 26, said outer casing 12 being formed of a polymer substrate direct coated on at least the outer surface thereof with a plasticised polyvinyl chloride (PVC) polymer, wherein said impact absorbing material 26 contains, or is at least partially coated with, a flame-retardant substance, wherein said polymer substrate has a tensile strength of at least 2000N/50mm, a tear strength of at least 300N and can withstand a temperature of -15ËšC and wherein said inner cushioning means comprises an envelope having an inner layer 24 and at least reinforcing layer 20 surrounding said inner layer 24, wherein said layers 20, 24 contain, or at least partially coated with, a flame retardant substance.

Description

A FALL ARREST UNIT

This invention relates generally to a unit for absorbing impact, and more particularly to a fall arrest unit intended to prevent injury of individuals or damage to articles resulting from a fall.

The present invention finds particular, although not exclusive, utility in military, aviation and other extreme environments. Legislation demands that a risk assessment must be carried out to either prevent a person from falling from a height or, if that is not practical, then arresting any fall so that a person does not sustain injury. Military personnel: for example, are often required to carry out inspection and maintenance of aircraft, which often involves individuals having to work on an aircraft, which are usually high enough that a fall therefrom would result in injury.

UK patent no. GB2367877 describes an impact absorbing unit having an outer casing which contains a loose fill of compressible particles, for example, expanded polystyrene.

Such known units are unsuitable for use in specialist environments, such as aircraft hangars and the like, where highly corrosive substances, such as aircraft fuel, cause corrosion of the outer casing and the inner filling, which clearly has an adverse effect on the lifespan and effectiveness of the unit. The known units are further unsuitable for use in extreme environments, such as very hot or very cold climates, because the outer casing is prone to cracking or otherwise degrading at extreme temperatures.

It is therefore an object of the present invention to address these issues and provide a fall arrest unit which alleviates the problems described above.

Thus, in accordance with the present invention there is provided a fall arrest unit comprising an outer casing and an inner cushioning means housing loose-fill, impact absorbing material, said outer casing being formed of a polymer substrate direct coated on at least the outer surface thereof with a plasticised polyvinyl chloride (PVC) polymer.

Preferably, the outer casing is formed of a polymer substrate direct coated on both sides thereof with a plasticised PVC polymer, to provide maximum protection for the unit in extreme temperatures and/or in the presence of corrosive substances.

The polymer substrate is preferably a thermoplastic polymer substrate, such as nylon or polyester.

The impact-absorbing material is preferably expanded polystyrene, which beneficially contains, or is at least partially coated with (by spraying, for exam pie), a flame-retardant substance.

The inner cushioning means beneficially comprises an envelope formed of a plurality of layers of material. For example, the envelope may comprise an inner layer of substantially water-proof material, a reinforcing layer surrounding said inner layer, and a protective layer surrounding said reinforcing layer. The layers preferably contain, or are at least partially coated with, a flame retardant substance The outer casing is preferably formed of a plurality of panels, stitched or otherwise connected together to form an open-ended enclosure, the outer casing further comprising an end panel for sealing said enclosure by releasable fixing means, preferably a zip. The end panel beneficially comprises a flap for covering said releasable fixing means when said enclosure is in a sealed configuration.

The outer casing preferably further comprises means for releasably connecting two or more fall arrest units together.

Embodiments of the present invention will now be described by way of examples only and with reference to the accompanying drawings, in which: Figure 1 is a schematic end cross-sectional view of a fall arrest unit according to an exemplary embodiment of the present invention; Figure 2 is a schematic perspective view of the fall arrest unit of Figure 1; Figure 3 is a schematic perspective view of a fall arrest unit according to a first exemplary embodiment of the present invention; and Figure 4 is a schematic perspective view of a fall arrest unit according to a second exemplary embodiment of the present invention.

Referring to Figures 1 and 2 of the drawings, there is shown a fall arrest unit generally indicated 10. The unit 10 comprises an outer casing 12 formed from a wear-and corrosion-resistant material, and inner cushioning means in the form of an envelope 14 defining an inner recess 16. The outer casing 12 is formed of plasicised PVC polymer direct coated onto one or, more preferably, both sides of a polyester or nylon substrate. The specialist coating may contain one or more of a flame retardant substance, biocide/fungicide and UV stabiliser, as required. The outer casing is thus highly robust, with tensile strength of at least 2000NI5Omm and a tear strength between around 300 and 400 N, and it is designed to withstand temperatures as low as -15 or -20 oC without cracking.

The inner cushioning means 14 is preferably formed of three layers: an inner layer 24 comprising a polythene membrane, beneficially having perforations therein to allow air to escape therefrom quickly in the event of an impact, thereby to prevent the membrane from bursting; a reinforcing layer 22, surrounding the inner layer 24, which reinforcing layer may be formed of nylon netting or similar material; and a protective layer 20 which may be formed of 100% cotton. Any or all of the three layers 20, 22, 24 may be impregnated or coated with a flame retardant substance.

Within the inner recess 16 defined by the envelope 14, there is provided loose fill particulate material 26, such as expanded polystyrene or the like. The particulate material is, ideally, similar to memory foam', in that it absorbs impact and, when any force thereon is removed, it returns to its original configuration.

The particulate material is preferably sprayed with a flame retardant substance, examples of which are known in the art.

The use of what is effectively a three-layer structure around the impact absorbent material is particularly advantageous because even if one of the layers tears or is otherwise compromised, the impact-absorbing particulate material is still effectively held in position by the other layers, such that the effectiveness of the unit is not compromised as a result.

Referring particularly to Figure 2 of the drawings, the envelopes 14 filled with particulate material are housed within the outer casing 12, wherein the number of envelopes 14 provided is entirely dependent on the size of the unit 10. In the illustrated example, six filled envelopes are used to fill the outer casing 12, but different sizes and shapes of unit are envisaged and the invention is in no way intended to be limited in this regard.

Referring now to Figure 3 of the drawings, the outer casing 12 is formed from a number of panels, joined together to form an open-ended enclosure, for receiving the envelopes filled with particulate material. In a preferred embodiment, the panel forming the base of the unit, in use, is formed of a double layer of direct coated PVC material, whereas the panel forming the top surface, in use, may be a single layer.

Where the edges of the panels meet, they are pressed together and stitched over the join; a chain overlock stitch is preferred as this type of stitching serves to secure earlier stitches which results in a strong join. In this way, a rigid upstanding rib is formed at the periphery of the panels which helps to maintain the shape of the unit. If the stitches are close together, the result is a substantially continuous sheath which helps to protect the most vulnerable part of the fall arrest unit.

Thus, the open-ended enclosure allows insertion of a number of envelopes, pro-filled with particulate material and sealed prior to insertion into the outer casing 12. Once the envelopes have been inserted into the outer casing 12, the unsecured end panel 28, rather by means of further stitching or, more preferably, by means of a heavy-duty zip (not shown) or other releasably fastening means. The use of releasably fastening means to seal the unit has a number of advantages associated with it. Firstly, it avoids the need to stitch the final seam, which can otherwise be difficult with conventional sewing machinery due to the shape and size of the completed unit, and also the thickness and robustness of the outer casing material. Secondly, it allows convenient access to the enclosure to check and replace the material4illed envelopes if necessary.

A flap 30 is provided at the outer edge of the end panel 28 which is configured to cover and protect the fastening means, and can be secured thereover, to the unit, by means of co-operative hook-and-eye fastening strips 32, or similar.

One or more open-topped pockets 34 may be provided on the outer surface of the unit, for receiving labels or similarly informative documentation, and loops or handles 36 may be provided for enabling the unit to be manoeuvred as required.

The units of the present invention can be made of any suitable size or shape. In one exemplary embodiment, the units are substantially rectangular and of a height substantially 600mm. Also, for other applications, the height of the unit may be required to be up to 1200mm. However, the invention is not in any way intended to be limited in this regard. For many applications, it may be necessary to employ a plurality of units in order to cover a predetermined floor space around the structure on which operatives are required to work. For this purpose, fastening means may be provided on the individual units to allow them to be connected together (either side-by-side or in a stacked configuration) and prevent their relative movement during use or in the event of an impact. As shown in Figure 3 of the drawings, such fastening means may comprise one or more straps 38, stitched onto a side panel of the unit, and corresponding loops stitched onto the opposing side panel of the unit, wherein two units can be connected together, side-by-side or in a stacked configuration, by inserting a belt 38 of a first unit through a corresponding loop 40 of a second unit, and securing the belt 38 by means of, for example, a hook-and-loop fastening panel or the like.

It will be appreciated by a person skilled in the art that modifications and variations can be made to the described embodiments without departing from the scope of the invention as claimed. For example, the unit need not be rectangular, or even of symmetrical shape, and could be shaped to suit the specific application for which it is intended to be used. For example, in the case of an aviation environment, where the units are required to be used below an aircraft, units could be provided which have a triangular front end, as shown in Figure 4 of the drawings, for use around the nose' of an aircraft.

Claims

CLAIMS1. A fall arrest unit comprising an outer casing and an inner cushioning means housing loose-fill, impact absorbing material, said outer casing being formed of a polymer substrate direct coated on at least the outer surface thereof with a plasticised polyvinyl chloride (PVC) polymer.
2. A fall arrest unit according to claim 1, wherein said outer casing is formed of a polymer substrate direct coated on both sides thereof with a plasticised PVC polymer.
3. A fall arrest unit according to claim 1 or claim 2, wherein said polymer substrate is a thermoplastic polymer substrate.
4. A fall arrest unit according to any one of the preceding claims, wherein said substrate is formed of nylon or polyester.
5. A fall arrest unit according to any one of the preceding claims, wherein said impact-absorbing material is expanded polystyrene.
6. A fall arrest unit according to any one of the preceding claims, wherein said impact-absorbing material contains, or is at least partially coated with, a flame-retardant substance.
7. A fall arrest unit according to any one of the preceding claims, wherein said inner cushioning means comprises an envelope formed of a plurality of layers of material.
8. A fall arrest unit according to claim 7, wherein said envelope comprises an inner layer of substantially water-proof material.
9. A fall arrest unit according to claim 8, wherein said envelope comprises a reinforcing layer surrounding said inner layer.
10. A fall arrest unit according to claim 9, wherein said envelope comprises a protective layer surrounding said reinforcing layer.
11. A fall arrest unit according to any of claims 7 to 10, wherein said layers contain, or are at least partially coated with, a flame retardant substance.
12. A fall arrest unit according to any one of the preceding claims, wherein said outer casing is formed of a plurality of panels, stitched or otherwise connected together to form an open-ended enclosure, the outer casing further comprising an end panel for sealing said enclosure by releasable fixing means.
13. A fall arrest unit according to claim 12, wherein said releasable fixing means comprises a zip.
14. A fall arrest unit according to claim 12 or claim 13, wherein said end panel comprises a flap for covering said releasable fixing means when said enclosure is in a sealed configuration.
15. A fall arrest unit according to any one of the preceding claims, wherein said outer casing further comprises means for releasably connecting two or more fall arrest units together.Amended claims have been filed as follows:-CLAIMS1. A fall arrest unit for use in military, aviation and other extreme environments, the unit comprising an outer casing and an inner cushioning means housing loose-fill, impact absorbing material, said outer casing being formed of a polymer substrate direct coated on at least the outer surface thereof with a plasticised polyvinyl chloride (PVC) polymer, wherein said impact absorbing material contains, or is at least partially coated with, a flame-retardant substance, wherein said polymer substrate has a tensile strength of at least 2000N/5Omm, a tear strength of at least 300N and can withstand a temperature of -15CC and wherein said inner cushioning means comprises an envelope having an inner layer and at least reinforcing layer surrounding said inner layer, wherein said layers contain, or at least partially coated with, a flame retardant 0') 15 substance.(,Q 2. A fall arrest unit according to claim 1, wherein said outer casing is formed of a polymer substrate direct coated on both sides thereof with a plasticised PVC polymer.3. A fall arrest unit according to claim 1 or claim 2, wherein said polymer substrate is a thermoplastic polymer substrate.4. A fall arrest unit according to any one of the preceding claims, wherein said substrate is formed of nylon or polyester.5. A fall arrest unit according to any one of the preceding claims, wherein said impact-absorbing material is expanded polystyrene.6. A fall arrest unit according to claim 6, wherein said envelope comprises an inner layer is formed of substantially water-proof material.7. A fall arrest unit according to any of the preceding claims, wherein said envelope comprises a protective layer surrounding said reinforcing layer.8. A fall arrest unit according to claim 7, wherein said protective layer contains, or is at least partially coated with, a flame retardant substance.9. A fall arrest unit according to any one of the preceding claims, wherein said outer casing is formed of a plurality of panels, stitched or otherwise connected together to form an open-ended enclosure, the outer casing further comprising an end panel for sealing said enclosure by releasable 0') 15 fixing means.(0 10. A fall arrest unit according to claim 9, wherein said releasable fixing means comprises a zip.11. A fall arrest unit according to claim 9 or claim 10, wherein said end panel comprises a flap for covering said releasable fixing means when said enclosure is in a sealed configuration.12. A fall arrest unit according to any one of the preceding claims, wherein said outer casing further comprises means for releasably connecting two or more fall arrest units together.