AU2005229646A1 - A safety device - Google Patents

Description

P/00/011 Regulation 3.2

AUSTRALIA

Patents Act 1990 COMPLETE SPECIFICATION STANDARD PATENT Invention Title: A safety device The following statement is a full description of this invention, including the best method of performing it known to us: 004731634

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A safety device 0 MField of the invention This invention relates to a safety device and in particular to an attachment which extends between a safety belt, safety harness or the like particle and a fixture.

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5 Background of the invention

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S Workers exposed to the danger of falling often wear safety harnesses or belts. Typically a lifeline or lanyard is attached to the safety harness or belt and in turn the lanyard is securely affixed to a convenient anchorage point. Should the worker fall, his descent is quickly checked by the lanyard.

There are a number of situations when a worker exposed to the danger of falling is able to safely work within a certain distance of a secure point but runs a greater risk of falling beyond that prescribed distance. Under these circumstances workers will often forego the use of a properly constructed safety line or lanyard and instead use a rope or other type of safety line specifically cut to a particular length to maintain the worker within the relatively safe working area and prevent the worker straying into the dangerous area. In this way the safety line acts as a form of leash defining the area within which the worker can operate. This method of restraint requires the worker to have the length of the safety line adjusted specifically to the particular working environment and is not particularly well suited for using the safety line in different working environments.

Additionally, if the worker is working at a height below an anchorage point, the worker may not need the full length of safety line to complete the task at hand. Hence the worker may wish to restrict the distance they can fall by limiting the length of their safety line.

Summary of the invention According to one embodiment there is provided a safety device including a harness attachment, a support attachment for connection to an anchorage point, an elongate 004731634 2

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restraint between the harness attachment and the support attachment and a means for adjusting the length of the elongate restraint. Preferably the elongate restraint is O provided with indicia to indicate the distance between the support attachment and a i reference point on the elongate restraint or the harness attachment.

In one form of the invention the safety device is a fall arrest device such as a lanyard.

The elongate restraint may be provided with an energy absorbing section. The energy absorbing section includes a sacrificial webbing sewn in a gathered section and provides restraint to the worker under normal tensions in the restraint. However, when subjected to a predetermined heavy load, such as when a worker falls from height, the sacrificial webbing in the energy absorbing section is subjected to the predetermined load causing the sacrificial webbing of the gathered section to tear, while remaining continuously attached at the ends. The gathered section thus extends up to its full length and acts as a shock absorber should the worker incorrectly adjust the length of the lanyard and fall from the secured working environment.

Therefore by providing a means of adjusting the length of the elongate restraint, with indicia markings to indicate the distance between two reference points on the elongate restraint such as the support attachment and harness attachment, the safety device can be quickly and easily adjusted to the correct length.

In a second aspect, the invention further provides a method of applying a fall arrest device including the steps of: determining the maximum distance from an anchorage point which a worker can safely work; setting a fall arrest device to indicate the maximum distance securing the fall arrest device to a safety harness; and securing the fall arrest device to an anchorage point.

004731634 3 SBrief description of the drawings O Figure 1 is an illustrative view of an embodiment of the invention affixed to a secure 0 point and a safety harness of a worker; Figures 2-4 are examples of the adjustment setting of the lanyard in accordance with 5 the embodiment shown in Figure 1; and

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c Figure 5 is an illustration showing the adjustment of the lanyard.

cDetailed description of the embodiments It will be understood that the invention disclosed and defined in this specification extends to all alternative combinations of two or more of the individual features mentioned or evident from the text or drawings. All of these different combinations constitute various alternative aspects of the invention.

Referring to Figure 1, a worker 1 is shown attached to a safety device in accordance with an embodiment of the invention. The worker is provided with a safety harness 2 consisting of shoulder straps 3 connected to a waist belt 4 and groin straps 5. The harness 2 is provided with an attachment point such as a D ring 6. The harness 2 is adjustable to enable it to be snugly fit to the worker. Other types of safety equipment which provide a secure point of attachment to a person or equipment such as safety belts may be used with the invention without departing from the inventive concept or scope of the invention. However for the purpose of describing an embodiment of the invention, the safety equipment attached to the safety device of the invention will be referred to as a safety harness.

The safety device according to an embodiment of the invention comprises a harness attachment 10, a support attachment 11 and an elongate restraint 12 extending between the harness attachment 10 and the support attachment 11. The harness attachment 10 and support attachment 11 are preferably double acting hooks but other types of safety line terminations which secure a safety line to an anchorage point and a safety harness or belt may be used.

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The elongate restraint may be made from a synthetic webbing material or other type of suitable material. Suitable materials for the webbing would be readily apparent to a Sperson skilled in the art.

As shown in Figures 2-4, the safety device is provided with a means for adjusting the length of the elongate restraint. To adjust the length of the elongate restraint may be provided with an extendable section 16 having an adjustment means and a fixed section 17 connected to each other by means of a connector such as a D ring 18. The 0 adjustment means may be a buckle 13 which receives both the free end 14 of the N, elongate means. The elongate restraint passes through buckle 13 and is then looped through D ring 18 before being fed back through buckle 13 to secure the relative positions of the captured section 15 of the elongate restraint and the doubled over lower captured section 20 extending from the D ring to the buckle 13.

The elongate restraint is provided with indicia and preferably a plurality of indicia. The indicia may be printed or sewn into the adjustable section of the elongate restraint to permanently indicate the length between two reference points such as the support attachment 11 and a point on the elongate restraint. The preferred reference points are the support attachment 11 and the harness attachment The indicia on the adjustable section 16 indicates the distance between the support attachment 11 and the harness attachment 10 as an indication of the maximum distance which the workers harness can move from the anchorage point. Alternatively the indicia can indicate the distance between the secured attachment and the connection between the fixed section and the adjustable sections of the elongate restraint or between any suitable positions on the lanyard.

The markings on the elongate section of the lanyard are at regular intervals along the extendible section providing an indication of the distance between the marking and a fixed point on the lanyard preferably the support attachment. This indicia is generally facing upwardly on the adjustable upper section 15 of the elongate restraint. Thus, the exposed indicia to which is closest to a second fixed point such as the D ring is an indication of the distance between the prescribed reference points on the safety device.

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The fixed section of the elongate restraint may be provided with a shock absorbing section 19 comprising a number of gathered layers of webbing held together by O sacrificial webbing. The sacrificial webbing on the gathered section tears when placed under a load which is in excess of an initial predetermined lower limit. In this way the lanyard provides a shock absorbing effect should the worker fall from his workplace.

The tearing of the sacrificial webbing between the gathered sections act to decelerate the worker and provide a less abrupt arrest to his fall as he approaches the maximum c extension of the lanyard. Once the lanyard has been subjected to a load in excess of its O predetermined lower limit, it should be replaced for safety reasons.

In order to properly apply the safety device of the invention, the appropriate length of safety device between the worker 1 and anchorage point 30 is calculated or measured.

The calculated or measure distance should be sufficient to prevent a worker falling. If the worker is working from a ladder (as shown in Figure 1) or other platform where a fall cannot be prevented, then the set length of the safety device should be such that there is either sufficient ground clearance or the worker will not strike a fixture, such as a beam, in the event of a fall. Under these circumstances the length of the safety device should be such that the fall risk of the worker does not exceed 2 metres.

As shown in Figure 5, the length of the safety device is then adjusted to the appropriate length by feeding the upper section 15 of the capture section through the D ring 18 until the indicia of upper section 15 corresponding to the appropriate length is adjacent the D ring 18. The loose sections of webbing in both the upper and lower sections of the captured section 16 are then drawn tight through the buckle 13 to complete the adjustment.

The safety device is then attached to the anchorage point at one end and the attachment point on the safety harness or belt at the other. The safety device preferably should be attached with the shock absorbing section closest to the worker.

In this way, the correct length of safety device or lanyard can be set and the worker secured at an appropriate distance from an anchorage point.

Claims (5)

1. 2. The safety device of claim 1 wherein the elongate restraint is provided with indicia to indicate the distance between the support attachment and a reference point on the elongate restraint or the harness attachment.
2. 3. The safety device of claim 1 or 2 wherein the device is a fall arrest device.
3. 4. The safety device of any one of the preceding claims wherein the elongate restraint is provided with an energy absorbing section. The safety device of claim 4 wherein the energy absorbing section includes a sacrificial webbing sewn into a gathered section.
4. 6. The safety device of claim 5 wherein the sacrificial webbing in the gathered section tears when subjected to a predetermined load.
5. 7. A method of applying a fall arrest device including the steps of: determining the maximum distance from an anchorage point which a worker can safely work; setting a fall arrest device to indicate the maximum distance securing the fall arrest device to a safety harness; and 004731634 7 O securing the fall arrest device to an anchorage point. O 8. The method of claim 7 wherein the fall arrest device is a safety device according S to any one of claims 1, 2, 4, 5 or 6. IN 9. The safety device substantially as hereinbefore described with reference to the 5 accompanying drawings. Dated 31 October 2005 Freehills Patent Trade Mark Attorneys Patent Trade Mark Attorneys for the Applicant: Bacou Dalloz Australia Pty Ltd