Webbing and webbing fittings

Abstract

A length of webbing including a stopper provides a tensile member for use with a hardware component such as a buckle through which the webbing but not the stopper may pass. The stopper has two blocking components disposed in contact with opposite sides of the webbing, and a fastener that interconnects the blocking components. In use on application of a load to the webbing, the stopper contacts the hardware and load is transmitted to the hardware by the stopper and to the transverse weft fibres of the webbing by the fastener. Beyond a threshold load, the weft fibres will fail, thereby dissipating energy. The stopper is removable, enabling the webbing and a harness with which is used or is a part to be tailored according to user size, clothing or circumstances. The stopper may be located as desired and excess tail webbing be trimmed away providing a neat and tidy webbing and reducing the risk of fouling or distracting the user.

Description

[0001] WEBBING AND WEBBING FITTINGS

[0002] The present invention relates to webbing and webbing fittings.

[0003] Lengths of webbing of woven polymer are used in many applications in which they serve as tensile members. Lengths of webbing may be interconnected to one another or to parts of a larger structure by hardware components, including, for example, plates, buckles and loops. The hardware components may allow the position of the webbing to be adjusted, by allowing the webbing to slide or locking it in place under the control of a user. As one example, lengths of webbing may be used to form structural tensile members in a harness suitable for supporting a person working at height or as for a fall-arrest harness for use by a climber, with the adjustment provided by the hardware allowing the harness to be accommodated to the requirements of an individual user. It will be understood that in an application such as a harness, the webbing may be a safety-critical component.

[0004] The hardware is typically configured to lock the webbing until a user intervenes to release it for adjustment. This is a safe default configuration that prevents uncontrolled movement of the webbing through the hardware component. However, it is important that some provision is made to ensure that an end of the webbing cannot be pulled through and become detached from the hardware if an error is made by the user or if the hardware fails to lock. The traditional approach, shown in Figures la and lb, is to form a stopper by folding an end portion of the webbing 10 back on itself one or more times to form a loop 12 and making the loop secure by stitching 14. The stopper resists being pulled through an item of hardware such as a buckle and preferably acts on the buckle to increase its grip on the webbing. The stopper is typically tested to withstand a predetermined loading (for example, 2kN) without pulling through the buckle.

[0005] The conventional stopper described above has several disadvantages. The length of the webbing is fixed by the manufacturer; the user cannot alter the length without cutting off the sewn end and re-sewing to form a new stopper, which may invalidate a warranty or a certification and compromise safety. The sewn end of the webbing is generally one of the final operations performed during manufacture of a harness, which at that stage in manufacture is large, bulky and heavy. This makes it unsuited to being placed on to a sewing machine to create the sewn end stop. If a mistake or error is made at this point, then the harness may require deconstruction to remedy and new webbing components installed.

[0006] An aim of this invention is to provide a stopper for use on webbing that overcomes or at least ameliorates these disadvantages.

[0007] To this end, from a first aspect, this invention provides a length of webbing that serves as a tensile member in combination with a hardware component through which the webbing passes, and a stopper carried on the webbing, which cannot pass through the hardware component, wherein the stopper comprises first and second blocking components disposed in contact with opposite sides of the webbing, and a fastener that interconnects the blocking components, the fastener passing through the webbing.

[0008] When the webbing is under load, the stopper and webbing at or near the location where the stopper passes through the webbing, act together to dissipate energy applied to the webbing as the stopper engages with the hardware. As load increases, the stopper bears against the hardware and the fastener bears against the transverse weft fibres of the webbing. The fibres may fail above certain loads whereby the stopper and the webbing, in combination, act to dissipate this energy. The webbing and stopper, in combination, serve as a tensile member.

[0009] The invention provides a length of webbing including a stopper carried on the webbing wherein the webbing and stopper in combination serve as a tensile member in combination with a hardware component having an aperture through which the webbing passes the stopper being dimensioned to preclude its passage through the aperture wherein the stopper comprises first and second blocking components disposed in contact with opposite sides of the webbing, and a fastener that interconnects the blocking components, the arrangement being such that upon the stopper contacting the hardware load is transmitted to the hardware by the stopper and to the transverse weft fibres of the webbing by the fastener and beyond a threshold load, the weft fibres will fail, thereby dissipating energy,.

[0010] In another aspect, the invention provides for the use of a tensile member comprising a stopper and a length of webbing in combination with a hardware component comprising an aperture through which the webbing passes but through which the stopper cannot pass, to transmit a load applied to the length of webbing to the hardware component by engagement of the stopper against the hardware component wherein the stopper comprises first and second blocking components disposed in contact with opposite sides of the webbing, and a fastener that interconnects the blocking components, the fastener passing through the webbing and being configured to engage with transverse weft fibres of the webbing in order to dissipate energy where the load exceeds a threshold level.

[0011] The invention also provides a method of arresting the passage of a tensile member, which comprises a stopper and a length of webbing, through a hardware component comprising an aperture through which the webbing may pass but through which the stopper cannot pass, by transmitting a load applied to the length of webbing to the hardware component by engagement of the stopper against the hardware component wherein the stopper comprises first and second blocking components disposed in contact with opposite sides of the webbing, and a fastener that interconnects the blocking components, the fastener passing through the webbing and being configured to engage with transverse weft fibres of the webbing in order to dissipate energy where the load exceeds a threshold level.

[0012] Most preferably, the fastener is removable whereby the stopper can be removed from the webbing. For example, the fastener may be a threaded fastener, such as a screw. It may be a screw with a pointed end that can penetrate the webbing by displacing webbing fibres without severing the fibres. In embodiments in which the fastener is threaded, e.g., a screw, it may pass through a bore in the first blocking component within which it is free to turn and slide. The screw may be in threaded engagement with the second blocking component. In such embodiments, the screw is tightened to place the fastener in tension to clamp the webbing between the first and second blocking components. The second blocking component may have a bore into which a threaded shaft of the screw enters and in which it forms a thread. Alternative forms of fastener may be used. For example, a bolt may be threaded into a nut or a threaded insert in the second blocking component

[0013] Advantageously, the stopper may be removed and placed at a different location on the webbing. The user may therefore tailor the length of webbing and sizing of a harness of which the webbing is a part to provide a snug fit. As desired, any excess webbing may be trimmed to provide a tidier and neater finish to the webbing and to avoid tails of webbing distracting the user or potentially becoming fouled during use. The removability of the stopper also allows a harness of which the webbing and stopper is a part to be adjusted when the user is wearing different clothing, for example in different seasons. The removability of the stopper also allows the harness to be adjusted for use by different users, providing economy of use in a commercial environment where different users may need to use the same equipment.

[0014] The invention accordingly provides a significant enhancement in user convenience, flexibility of use and safety and facilitates use by multiple users.

[0015] The blocking components may be formed as polymer mouldings. Alternatively, the blocking components may be metal (typically metal alloy) formed by one or more of forging, casting and machining. The blocking components are formed individually (e.g., as separate mouldings) or alternatively are interconnected portions of a single component

[0016] The webbing may be a component of an item of personal protective equipment, such as a harness.

[0017] From a second aspect, this invention provides an assembled item such as an item of personal protective equipment that includes a length of webbing embodying the first aspect of the invention. In such an assembled item, the webbing typically cooperates with a hardware component For example, the webbing may be a component of a harness, such as a fall-arrest harness or a harness for supporting a person working at height. The webbing may be a component of many other items within which webbing is used in combination with hardware, such as a rucksack, load carrying equipment, among many others.

[0018] An embodiment of the invention will now be described in detail, by way of example, and with reference to the accompanying drawings, in which:

[0019] Figures la and lb show conventional webbing stoppers and have already been discussed;

[0020] Figures 2 and 3 are oblique and side views of a stopper embodying the invention;

[0021] Figures 4 and 5 are sectional and exploded views of the stopper of Figures 2 and 3;

[0022] Figures 6 and 7 are first and second polymer components of the stopper of Figures 2 and 3; Figure 8 shows a screw of the stopper of Figures 2 and 3 in position on a length of webbing;

[0023] Figure 9 shows alternative positions of the stopper of Figures 2 and 3 in place on a length of webbing;

[0024] Figure 10 shows the stopper of Figures 2 and 3 acting to prevent a length of webbing from being pulled through a buckle;

[0025] Figure 11 shows a screw of the stopper of Figures 2 and 3 in place on a length of webbing in an alternative arrangement;

[0026] Figure 12 shows a stopper embodying the invention under test;

[0027] Figure 13 shows in greater detail the stopper of Figure 12;

[0028] Figure 14 is a graph showing the load resisted by the stopper under test in Figure 12 against movement of the stopper in the webbing; and

[0029] Figures 15 and 16 show two alternative stoppers embodying the invention.

[0030] With reference to Figures 2 to 11, a stopper being an embodiment of the invention comprises three components: first and second blocking components being polymer mouldings 20, 22 and a metal fastener 24. Note that in alternative embodiments, the blocking components could be formed using other methods, such as forging, casting or machining, and might be formed from other materials such as composites or metals. They may also be formed by different regions of a single component

[0031] Each polymer moulding 20, 22 is of circular peripheral shape and is rotationally symmetrical about a centre axis A. In this embodiment, the mouldings 20, 22 are of substantially the same outer diameter. Each moulding 20, 22 has a bore 26, 28 of circular cross-section that extends through the moulding centred on the axis A. Each bore 26, 28 opens to an outer surface of the moulding 20, 22. The outer surface extends with an increasing diameter to a circular outer diameter of the moulding 20, 22, at which a short cylindrical portion 30, 32 is formed. The opening of the bore 26 of the first moulding 20 at the outer surface is countersunk at 34. The remainder of the bore 26 is cylindrical. The bore 28 of the second moulding 22 is cylindrical and of lesser diameter than the cylindrical part of the bore 26 of the first moulding 20.

[0032] Each moulding 20, 22 has a contact face shown in Figures 6 and 7, respectively. The contact faces have ribs 36, 38 that extend radially outwardly from the bores 26, 28 to join an annular outer surface 40, 42. Several projecting studs are formed on the contact faces. In this embodiment, these are formed as conical spikes, with the intention that they can penetrate into the webbing between its warp and weft fibres. In the case of the first moulding 20, the studs 44 are at radially inner end portions of the ribs 36 surrounding the bore 26. In the case of the second moulding 22, the studs 46 are at radially outer end portions of the ribs 36 at the annular outer surface 42.

[0033] The fastener 24 in this embodiment is a self- tapping screw with a countersink head 48 and threaded shaft 50 that ends in a point 52. The shaft is dimensioned to enable it to slide and turn freely through the bore 26 of the first moulding 20 and such that it can be threaded into the bore 28 of the second moulding 22.

[0034] Installation of the stopper onto a length of webbing 10 will now be described.

[0035] First, the first and second mouldings 20, 22 are placed on opposite sides of the webbing 10 and clamped in place at a preferred position along the length of the webbing and centrally across the width of the webbing 10. The mouldings 20, 22 are positioned such that their bores 26, 28 are coaxial and their contact faces are in contact with opposite surfaces of the webbing 10. The clamping force causes the studs 44, 46 to engage with the fibres of the webbing 110 to minimise or eliminate sliding or rotational movement of the moulding 20, 22 on the webbing 10. The shaft 40 of the fastener is then passed into the bore 26 of the first moulding 20 past the countersunk opening 34. The of the shaft 50 is brought into contact with a first surface of the webbing 10, whereupon the point 52 forms a hole 56 in the webbing 10 by displacing warp and / or weft fibres of the webbing 10 most preferably without damaging or severing the fibres. Alternatively, a hole 56 is formed in the webbing in a separate initial step, by displacing warp and / or weft fibres of the webbing 10. The shaft 50 of the fastener 24 is passed through the bore 26 of the first moulding 20. The fastener 24 is turned to engage the thread on the shaft 50 with the webbing 10 thereby drawing the shaft through the webbing 10 until its point 52 emerges from a second surface of the webbing 10, as shown in Figure 8 such that the point 52 enters its bore 28 of the second moulding 22.

[0036] The fastener 24 is then turned further, typically with the aid of a tool applied to its head 48, which causes the shaft 50 to advance into the bore 28 of the second moulding 22. The thread of the shaft 50 then engages with the bore 28, to form a thread in the wall of the bore 28. Turning of the fastener 24 continues, with the effect that the mouldings 20, 22 are pulled towards one another on opposite sides of the webbing 10 until its head 48 is forced into contact with the countersink 34 in the first moulding 20 causing the webbing 10 to become clamped between the mouldings 20, 22. As shown in Figure 4, the clamping action causes the studs 44, 46 to be pressed into the webbing 10, which resists movement of the mouldings 20, 22 (and therefore, the stopper) on the webbing 10.

[0037] Should a user decide that the stopper 18 is not in a preferred position on the webbing 10, then the fastener 24 can be undone, and the stopper 18 removed from the webbing 10. The installation procedure described above can then be repeated at another position on the webbing 10. The fibres of the webbing 10 will return towards their original position whereupon the hole 56 formed when the stopper 18 was first fitted will close (Figure 9). Clearly, it is also possible for several stoppers 18 to be installed at different positions on the webbing 10 and, unlike in the case of a conventional sewn stopper, a stopper embodying the invention can be located at any point along the length of the webbing 10.

[0038] Figure 10 shows the stopper of this embodiment of the invention in place on a length of webbing 10 acting to prevent the webbing being pulled through a piece of hardware 58. In this example the hardware is a plate being a component of a releasable buckle, but it could instead be one of many different types of hardware with which webbing cooperates.

[0039] An alternative embodiment of a stopper 60 embodying the invention on a length of webbing 10 is shown in Figure 11. In this embodiment, the webbing is folded back on itself to form a loop 62, the fastener being longer than in the first embodiment to enable it to pass through a double thickness of webbing. In other respects, this embodiment and its installation are similar to or identical to the embodiment described above.

[0040] In normal use, the stopper will be subject to relatively light loading, typically acting to prevent a user from manually pulling the end of webbing through a buckle during adjustment There is typically sufficient resistance to movement of the stopper form the clamping action to prevent movement of the stopper on the webbing under such loads. Events may arise in which the stopper will be subject to significantly greater loads, for example, where a buckle has failed to lock and webbing to which the stopper is applied is under load. In such events, movement of the stopper is primarily resisted by the fastener making contact with the transverse weft fibres of the webbing. If a threshold load is exceeded, the weft fibres will fail, and the stopper will be pulled along the length of the webbing, energy being dissipated within the webbing as subsequent weft fibres fail successively. Such an event is simulated by applying a load to a stopper on a length of webbing, as shown schematically in Figure 12.

[0041] In Figures 12 and 13, a stopper 18 abuts against a buckle 58 through which the webbing 10 passes. The buckle 58 is secured to a static attachment point 66 through a loop of webbing 68. Spaced from the stopper 18, a sewn loop 70 is formed in the webbing 10, the loop 70 being used to attach the webbing to test apparatus 72. A load L is applied by the test apparatus 72, which is resisted by the stopper 18 being unable to pass through the buckle 58. As the load L is displaced away from the attachment point 66 by a distance d, the load L applied by the test apparatus 72 increases until it reaches a threshold at which the fastener 24 of the stopper 18 it is pulled through one of the weft fibres of the webbing 10. This causes the fastener to be displaced along the webbing 10, which causes a stepwise reduction in the applied load L. This sequence repeats as the fastener 24 passes through successive weft fibres, as shown in Figure 14.

[0042] The threshold load may be specified according to a particular application to which the webbing will be put and may be specified by relevant standards. The threshold may be influenced by the clamping force applied to the webbing by the blocking components and / or by the strength of the webbing fibres. For example, a threshold in excess of 2kN may be achieved. A first alternative embodiment stoper is shown in Figure 15. In this embodiment, the first and second blocking components are formed as regions 120, 122 of a one-piece moulding and are interconnected by a flexible hinge region 123. The hinge region 123 is folded at one side of the webbing to bring the blocking components into contact with opposite faces of the webbing 10 before being fixed by the fastener 24. In other respects, this embodiment may be the same as that described above.

[0043] A second alternative embodiment stoper is shown in Figure 16. In this embodiment, the first and second blocking components are formed as regions 220, 222 of a one-piece moulding and are interconnected by two flexible webs 223 to form a tubular component. The webbing 10 is passed through the tubular component before being fixed by the fastener 24.

Claims

Claims1. A length of webbing that serves as a tensile member in combination with a hardware component through which the webbing passes, and a stopper carried on the webbing, which cannot pass through the hardware component, wherein the stopper comprises first and second blocking components disposed in contact with opposite sides of the webbing, and a fastener that interconnects the blocking components, the fastener passing through the webbing.

2. A length of webbing including a stopper carried on the webbing wherein the webbing and stopper in combination serve as a tensile member in combination with a hardware component having an aperture through which the webbing passes the stopper being dimensioned to preclude its passage through the aperture wherein the stopper comprises first and second blocking components disposed in contact with opposite sides of the webbing, and a fastener that interconnects the blocking components, the arrangement being such that upon the stopper contacting the hardware, load is transmitted to the hardware by the stopper and to the transverse weft fibres of the webbing by the fastener and beyond a threshold load, the weft fibres will fail, thereby dissipating energy.

3. A length of webbing according to claim 1 and claim 2 in which the fastener is removable whereby the stopper can be removed from the webbing.

4. A length of webbing according to any one of claims 1 to 3 in which the fastener is a threaded fastener.

5. A length of webbing according to claim 4 in which the fastener is a screw with a pointed end.

6. A length of webbing according to any one of claims 3 to 5 in which the fastener passes through a bore in the first blocking component within which it is free to turn and slide.

7. A length of webbing according to any one of claims 3 to 5 in which the fastener is in threaded engagement with the second blocking component8. A length of webbing according to claim 7 in which the fastener is tightened to clamp the webbing between the first and second blocking components.

9. A length of webbing according to claims 7 or claim 8 in which the second blocking component has a bore into which a threaded shaft of the screw enters.

10. A length of webbing according to claim 9 in which a thread within the bore of the second blocking component has a thread that is formed by the threaded shaft of the screw.

11. A length of webbing according to any preceding claim in which one or both blocking components are polymer mouldings.

12. A length of webbing according to any preceding claim in which one or both blocking components are metal.

13. A length of webbing according to any preceding claim in the blocking components are formed individually.

14. A length of webbing according to any preceding claim in the blocking components are portions of a single component15. A length of webbing according to any preceding claim being a component of an item of personal protective equipment16. A length of webbing according to claim 15 being a component of an item of harness.

17. An assembled item that includes a length of webbing according to any preceding claim.

18. An assembled item according to claim 17 in which the length of webbing cooperates with a hardware component19. An assembled according to claim 17 or claim 18 that is that is an item of personal protective equipment.

20. An item of personal protective equipment according to claim 19 that is a harness.

21. An item of personal protective equipment according to claim 19 that is a fall-arrest harness or a harness for supporting a person working at height22. Use of a tensile member comprising a stopper and a length of webbing in combination with a hardware component comprising an aperture through which the webbing passes but through which the stopper cannot pass, to transmit a load applied to the length of webbing to the hardware component by engagement of the stopper against the hardware component wherein the stopper comprises first and second blocking components disposed in contact with opposite sides of the webbing, and a fastener that interconnects the blocking components, the fastener passing through the webbing and being configured to engage with transverse weft fibres of the webbing in order to dissipate energy when the load exceeds a threshold level.

23. A method of arresting the passage of a tensile member, which comprises a stopper and a length of webbing, through a hardware component comprising an aperture through which the webbing may pass but through which the stopper cannot pass, by transmitting a load applied to the length of webbing to the hardware component by engagement of the stopper against the hardware component wherein the stopper comprises first and second blocking components disposed in contact with opposite sides of the webbing, and a fastener that interconnects the blocking components, the fastener passing through the webbing and being configured to engage with transverse weft fibres of the webbing in order to dissipate energy when the load exceeds a threshold level.

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