Patent Description:
A harness may be designed to support a user when working at height, to provide a comfortable body support for performing tasks when suspended from a rope access system. Alternatively or additionally, a harness may be used to arrest a user's fall, for example in a fall protection system used by a climber where there is the potential for a fall. Embodiments of the invention might find application to hardware used for rope access, industrial height safety, rescue, tactical applications, sport climbing, etc. Within this specification, example embodiments will be described that relate to harnesses intended for use in tree care, but this should not be taken to be limiting upon the range of applications of the invention.

This application relates to the components of a harness assembly which is of the general construction shown in <FIG> and <FIG>.

A known harness is shown in <FIG>. The harness comprises two leg loops <NUM> that, in use, encircle a user's thighs. Each leg loop <NUM> is connected to a padded back <NUM> that rests against the small of a user's back and has side wings that extend to above a user's hips when in use. The back has a waist webbing <NUM> that has ends that can be interconnected by a releasable front waist buckle <NUM>.

Each side wing has a side attachment arrangement <NUM>, shown in more detail in <FIG>. Each side attachment arrangement <NUM> connects the waist webbing <NUM> in the region of the wing through a riser webbing <NUM> to the corresponding leg loop <NUM>. In this known arrangement, the side attachment arrangement <NUM> comprises two metal loops <NUM>, <NUM> through which the waist webbing <NUM> passes. A variation on this harness, with a modified side attachment arrangement, is disclosed in <CIT>, which forms part of the state of the art by virtue of Art <NUM>(<NUM>) EPC.

Existing products and designs (e.g., as in <CIT>, which shows a harness according to the preamble of claim <NUM>) typically use a multitude of components to create a side attachment assembly. Not only does this produce a side attachment arrangement that is difficult to build into a harness at the manufacturing stage, it also gives limited opportunity following manufacture to replace textile elements, which are susceptible to wear through abrasion or other damage such as cuts, heat damage, and so forth. This can lead to users making their own solutions for repairing a worn side attachment assembly, which is undesirable because the effectiveness of such a repair cannot be guaranteed, or the harness being retired from service while many of its components are still well within their working lives.

Existing harnesses use a pair of symmetric forward attachment arrangements <NUM> as shown in <FIG> to suspend a flexible load bearing member <NUM> (also known as a "rope bridge") across the front of the harness. For use, the flexible load-bearing member <NUM> carries a sliding attachment device <NUM> which attaches to a climbing line. Typical known forward attachment arrangements include a connector <NUM> shown in <FIG> that is sewn in to the riser <NUM> and leg loop <NUM> webbing. The flexible load-bearing member <NUM> is tied in to the connector <NUM> during manufacture of the harness.

The flexible load bearing member <NUM> can be adjusted in length by repositioning a knot on the one end by the user which is time consuming and potentially hazardous for the user if done incorrectly.

An aim of this invention is to provide a harness that that overcomes or at least ameliorates these disadvantages.

To this end, from a first aspect, the present invention provides a harness for supporting a person working at height as set forth in claim <NUM>.

Replacement of the flexible load-bearing member can be achieved by removal of the retention components during servicing of the harness. Suitable formations for connection to the retention components, such as sewn loops, can be provided in the flexible load-bearing member during its manufacture, thereby avoiding the need to form them later, as is the case of a conventional flexible load-bearing member, which has to be securely knotted after it has been installed in the forward connection arrangement.

In embodiments of the invention, the flexible load-bearing member may include a loop and the retention components include a bar that when separate from the body can pass through the loop, and that, when connected to the body, is secured within the loop. The bar is typically secured to the body by bolts and nuts.

In such embodiments, the loop may be formed to include a region which will fail upon application of a force above a threshold but below a maximum working force to cause the effective length of the flexible load-bearing member to increase. This can limit the force that is applied to a user when the harness is acting to arrest a fall.

As an alternative to a bar, the retention component may include a knot blocker. That is, a component with a through hole through which a length of rope can pass, but which prevents the passage of a knotted rope. This can provide a more versatile form of attachment, allowing a user to adjust the length of the bridge by varying the position of a knot upon it.

To provide flexibility in operation, the retention components include an adjuster (e.g., a rope adjuster) that can be caused to grip the flexible load-bearing member at one of a range of positions. Typically, the adjuster allows the effective length of the flexible load-bearing member to decrease by application of a tensile force to a free end of the flexible load-bearing member. The adjuster may allow the effective length of the flexible load-bearing member to increase upon manual intervention by a user prior to application of a tensile force to the flexible load-bearing member.

The secured flexible connecting member passes through the body. This can ensure that the connection between the flexible load-bearing member and the body is not immediately lost in the event that the retention components become detached from the body, for example, as a result of a fastener becoming loose.

A harness embodying the invention may have two similar forward connection arrangements. Alternatively, it may have two dissimilar forward connection arrangements, for example, one having a loop and retention bar arrangement and the other having a rope adjuster arrangement as discussed above.

A harness embodying the invention may have one, two or more flexible connecting members each of which is removably secured to the harness by the or each forward connection arrangement. Typically, the body of each forward connection arrangement is permanently connected to a waist webbing that extends about the back of the harness and the body of each forward connection arrangement is permanently connected to a respective riser that is connected to a respective leg loop.

From a second aspect, the present invention provides a harness for supporting a person working at height comprising some or all of a back, leg loops, two forward connection arrangements and a flexible load-bearing member that extends between the connection arrangements, the forward connection arrangements serving to transferring load from the back and the leg loops to the load-bearing member, in which flexible load-bearing member includes an energy dissipation region which will fail upon application of a force above a threshold but below a maximum working force to cause the effective length of the flexible load-bearing member to increase.

The energy dissipation region may include a region that will fail progressively upon the load in the flexible load-bearing member being in excess of the threshold. For example, the energy dissipation region may include stitching that will progressively fail when the load in the flexible load-bearing member being in excess of the threshold.

The load-bearing member may include a load fuse which operates to transfer load between the flexible load-bearing member and the forward connection arrangement when the harness is in normal use and to fail when load in the flexible load-bearing member exceeds a threshold. Failure of the load fuse typically cause the transfer of load in the flexible load-bearing member to the energy dissipation region. The load fuse may comprise stitches that interconnect parts of the flexible load-bearing member.

Optional features of the invention from its first aspect may also be present in embodiments of the invention form its second aspect.

Embodiments of the invention will now be described in detail, by way of example, and with reference to the accompanying drawings in which:.

In the following description, the features described are to be considered as optional features of embodiments of the invention and features described with reference to one embodiment may be incorporated into another.

A harness embodying the invention has a forward attachment arrangement that includes a forward attachment assembly, as shown in <FIG>.

The forward attachment assembly comprises a body <NUM> and an attachment bar <NUM>.

The body <NUM> has a generally oval or slight figure-of-<NUM> peripheral shape and is formed from a single piece of metal by a combination of one or more of casting, forging and machining. The body <NUM> extends in a plane P, having inner and outer surfaces disposed to opposite sides of the plane, and its periphery can be considered as defining a region of the plane through which, six holes pass. The body is symmetrical about an axis A that extends within the plane and that forms a long axis of the body <NUM>.

A bridge hole <NUM> is centred on the axis A approximately one third of the distance along the axis A from a first end of the axis A. The bridge hole <NUM> has shape that is square with rounded corners and has a dimension approximately one third of the width of the body <NUM> in the plane P transverse of the axis A.

A first and a second webbing slot <NUM>, <NUM> are disposed to opposite sides of the axis A. Each slot <NUM>, <NUM> extends from a small distance from the axis A that lies between the bridge hole <NUM> and a first axial end of the body <NUM>, each slot <NUM>, <NUM> being centred along an arc that is a constant distance from a proximal part of the periphery of the body <NUM>.

There is an attachment hole <NUM> that extends symmetrically about the axis A to partially surround the bridge hole <NUM> and to extend to a second axial end of the body <NUM>. This imparts the body <NUM> with a D-shaped attachment portion extending from the bridge hole <NUM> in a direction away from the webbing slots <NUM>, <NUM>.

All four above-described holes <NUM>, <NUM>, <NUM>, <NUM> are formed with curved peripheries and without sharp corners to avoid the creation of stress risers within the body and within any object that is passed through the hole.

Two bolt holes <NUM> of circular cross-section pass through the body, at an axial position that is approximately half way along the axial extent of the bridge hole. Each bolt hole has one end portion, opening to the inner surface do the body <NUM>, that is countersunk.

The attachment bar <NUM> has a central portion <NUM> of round cross-section and two securing portions <NUM>. Each securing portion <NUM> has a flat mating surface. A bore extends through the securing portion <NUM> and opens perpendicular to the mating surface. At its opposite end, the bore has a hexagonal counterbore <NUM>.

To assemble the forward attachment assembly a self-locking nut <NUM> is inserted into the hexagonal counterbore <NUM> of each bore in the attachment bar <NUM>. A shaft of a respective cap screw <NUM> is inserted through each bolt hole <NUM> in the body from the countersunk end into a respective bore in the attachment bar <NUM> and then screwed into the nuts <NUM> in the attachment bar <NUM> and tightened such that the mating surfaces of the securing portions are clamped against the outer surface of the body <NUM>.

The above described attachment arrangement can be incorporated into a harness described in <FIG> as a replacement for the connector <NUM> (<FIG>). The body <NUM> is permanently installed in the harness by a leg riser webbing and a leg loop webbing passing through the webbing slots <NUM>, <NUM>. The flexible load-bearing member <NUM> is terminated at each end by a loop <NUM> that is permanently formed, for example by sewing. With the attachment bar <NUM> disconnected from the body, each loop <NUM> is passed through the bridge hole <NUM> of the body <NUM> of one of the forward attachment arrangements, as shown in <FIG>. The attachment bar <NUM> is then passed into the loop <NUM> such that it projects by approximately equal distances from both sides of the loop <NUM>. The forward attachment assemblies are then assembled as described in the last-preceding paragraph. This creates a secure connection between the flexible load-bearing member <NUM> and the forward connection arrangement, as shown in <FIG>.

The attachment hole <NUM> defines a loop within the body to which a connector, such as a carabiner, can be connected. This can be used to attach anchors that will help a user to maintain a desired position, or as a point from which items can be carried.

The attachment bar <NUM> can be considered to be attached to the body <NUM> semi-permanently, in that it will not be removed during normal use of the harness. However, the connection is made in such a way that the flexible load-bearing member <NUM> can be removed and replaced as necessary, as part of a service operation, without the requirement that the user of the harness performs potentially risky procedures such as the formation of secure knots in the flexible load-bearing member <NUM>.

It is possible to connect two flexible load-bearing members <NUM> to the same forward connection arrangement by passing the attachment bar through both of their loops <NUM>, <NUM>', as shown in <FIG>.

The flexible load-bearing members <NUM> shown above are formed of rope. However, they may have other configurations, such as being made of webbing, as shown in <FIG>.

In the above-described embodiments, enhanced security of attachment of the flexible load-bearing members <NUM> is obtained with some loss of flexibility of application, in that the length of the flexible load-bearing members <NUM> cannot be adjusted. Therefore, in a modification to the embodiments described above, one forward attachment arrangement is provided with means to adjust the length of the flexible load-bearing member <NUM>.

In a variation of the above embodiments, the flexible load bearing member <NUM> has at least one loop that is constructed in such a way as to limit the force that it can apply to the forward attachment arrangement during normal use to provide shock absorbance in the event that the harness acts to arrest a fall.

The principle of this design of these embodiments is that the attachment bar <NUM> is held within a double portion of webbing which is sewn together with a holding stitch and a further set of rippable stiches which once loaded by the bar, break sequentially to allow the bar to move through the webbing, effectively extending the length of the flexible load-bearing member <NUM> until an end-point is reached, with the result that the fall is arrested over a greater distance that would be the case where the loop is simply sewn at the end portion of the flexible load-bearing member <NUM>.

In a first arrangement of a flexible load-bearing member <NUM> shown in <FIG> and <FIG>, an extended loop <NUM> is formed at an end of the flexible load-bearing member <NUM>, which in this case is formed from webbing (although a similar arrangement could be formed from rope). The loop <NUM> is formed by folding an end portion of the webbing back on itself, and retaining it with a first, secure set of retaining stitches <NUM> that are close to the end of the loop nearest the centre of the flexible load-bearing member <NUM>. The retaining stitches <NUM> are formed for maximum strength - that is, they should fail only when the absolute load limit of the flexible load-bearing member <NUM> has been exceeded. Then, outwardly from the retaining stitches <NUM> is an unstitched region <NUM>, which has an outer boundary formed by a set of holding stitches <NUM>. Outwardly from the holding stitches <NUM> is a length of rippable stitches <NUM> that extends to close to the end of the flexible load-bearing member <NUM>.

The flexible load-bearing member <NUM> is installed onto the forward connection arrangement by passing the attachment bar <NUM> between lengths of the webbing at the unstitched region <NUM>.

During normal use, the attachment bar <NUM> is inserted into the unstitched region <NUM> to be held between the retaining stitches <NUM> and the holding stitches <NUM>, and the holding stitches will bear the normal working load transferred from the harness through the flexible load-bearing member <NUM>. The holding stitches <NUM> are configured such that they will fail in the event that the load applied to them by the attachment bar <NUM> exceeds a threshold that will be encountered during normal use of the harness, such as may arise during arrest of a fall, and as such may be described as a "load fuse". Once the holding stitches <NUM> have failed, load is transferred to the rippable stitches <NUM>, which are intended to fail sequentially as the attachment bar <NUM> passes through them, effectively lengthening the flexible load-bearing member <NUM> to lessen the decelerative forces applied by the harness to the user. In the event that all of the rippable stiches <NUM> fail, the attachment bar will come up against the end of the webbing loop, which transfers load back to the retaining stitches <NUM>, to apply sufficient force to arrest the user's fall.

In the modification of <FIG>, the length of webbing in which the rippable stitches <NUM> is formed is folded over upon itself several times. The purpose of this modification is to reduce the length of the flexible load-bearing member <NUM> that projects beyond the forward attachment arrangement. The folds can be maintained by light stitching or by a removable retaining member, for example, formed of flexible elastic material.

The load limiting arrangement of <FIG> may be provided at both ends of the flexible load-bearing member or a just one end.

The arrangements of <FIG> use the same body <NUM> as in the embodiments described above. In place of the attachment bar <NUM>, a rope adjuster assembly <NUM> is secured to the body <NUM> by cap screws <NUM>. The rope adjuster assembly <NUM> comprises two blocks mirror-image <NUM>, <NUM>', each one being secured through a bolt hole <NUM> the body <NUM> by a respective cap screw <NUM> positioned symmetrically to opposite sides of the bridge hole <NUM>. A carrier bolt <NUM> extends through a bore in one block <NUM>' and is fixed by being threaded into a tapped bore in the other block <NUM>. A cylindrical boss <NUM> is carried on the carrier bolt <NUM> between the blocks <NUM>, <NUM>', the boss <NUM> being fixed against rotation about the carrier bolt <NUM>. Note that the shape of the boss may be adapted in accordance with the item that it is intended to interact with (a rope, webbing, etc.,) to ensure that the grip that it applies is optimised. For example, the surface that faces the cam might be concave, v-shaped or may otherwise diverge from the straight-sided shape shown.

A cam axle <NUM> extends between the blocks <NUM>, <NUM>', and on it a cam <NUM> is carried such that the cam <NUM> can rotate on the axle <NUM>. The cam <NUM> has a gripping surface <NUM> that faces generally towards the boss138, the gripping surface being at a radial distance from the cam axle <NUM> that increases as the rotational distance of the gripping surface <NUM> from the boss <NUM> increases. The gripping surface extends onto a projecting lobe <NUM> of the cam <NUM>. Gripping formations, such as transverse ridges or grooves, are formed on the gripping surface <NUM> to increase the friction that will occur between the gripping surface and an object sliding over it.

To assemble the forward attachment arrangement, a flexible load-bearing member <NUM> is passed through the bridge hole <NUM> and then placed between the blocks <NUM>, <NUM>'. The boss <NUM> and the carrier bolt <NUM> are then fitted, so trapping the flexible load-bearing member <NUM> between the boss <NUM> and the cam <NUM>, with the flexible load-bearing member <NUM> being in contact with the gripping surface <NUM>. The rope adjuster assembly <NUM> is then bolted to the body <NUM>, which is the same as is the case in the other embodiments described herein.

The cam <NUM> and the flexible load-bearing member <NUM> are shaped and dimensioned such that when the cam <NUM> is rotated away from the body, such that the distance between the gripping surface <NUM> and the boss <NUM> is at its greatest, the flexible load-bearing member <NUM> is gripped, such that linear movement of the flexible load-bearing member <NUM> through the rope adjuster assembly <NUM> will urge the cam to rotate. Pulling the flexible load-bearing member <NUM> through the rope adjuster assembly away from the body <NUM> urges the cam to turn to a position that maximises the distance between the gripping surface <NUM> and the boss <NUM>. In this position, the flexible load-bearing member <NUM> can pass through the rope adjuster assembly <NUM> with some resistance. If the flexible load-bearing member <NUM> is pulled in the opposite direction, this urges the cam <NUM> to rotate in a direction that would reduce the distance between the gripping surface <NUM> and the boss <NUM>. If a user intervenes to prevent this rotation by applying force to the cam lobe <NUM>, the flexible load-bearing member <NUM> can move linearly with some resistance. However, if the user does not intervene, the cam <NUM> will rotate so lessening the distance between the gripping surface <NUM> and the boss <NUM>. This has the effect of clamping the flexible load-bearing member <NUM> between the cam <NUM> and the boss <NUM>, thereby preventing further linear movement of the flexible load-bearing member <NUM>. This allows the user to lengthen or shorten the flexible load-bearing member <NUM> as required.

An end part of the load bearing member <NUM> has a formation that prevents it from being fully withdrawn from the rope adjuster assembly <NUM> (for example, a loop <NUM> as described above or any other formation that increases its diameter sufficiently to prevent it passing between the cam <NUM> and the boss <NUM>). This prevents the load bearing member <NUM> from becoming disconnected inadvertently as it is being lengthened by a user.

By suitable modification of the rope adjuster assembly, a flexible load-bearing member <NUM> formed from webbing can be used instead of one formed from rope.

In a variation shown in <FIG>, two cams <NUM>, <NUM>' are carried on the cam axle <NUM> and two bosses <NUM>, <NUM>' are carried on the carrier bolt <NUM>. A spacer plate <NUM> extends between adjacent cams <NUM>, <NUM>' and bosses <NUM>, <NUM>'. This allows use and independent adjustment of two flexible load-bearing members <NUM>.

It should be noted that it will normally be necessary to provide a rope adjuster assembly <NUM> on one of two forward attachment arrangements, with the other using a fixed connection, for example as described with reference to <FIG>.

<FIG> show a modification to the embodiment of <FIG>, although it should be understood that it can be applied to other embodiments described above. This embodiment includes a body <NUM> that is broadly similar to that described above, with modifications as will now be described.

Instead of lying within a flat plane P, the body <NUM> in this embodiment is curved, such that the attachment portion extends at a small angle (approximately <NUM>° in this example).

The opening to each bolt hole <NUM> in the outer surface is surrounded by a ridge <NUM>. At the inner surface, each bolt hole <NUM> is counterbored and is formed with a hexagonal cross-section <NUM> inwardly of the counterbore.

This embodiment further includes an attachment bar <NUM> that is broadly similar to that described above, with modifications as will now be described.

Each securing portion <NUM> is formed with a recess <NUM> that surrounds the bore where it emerges from the mating surface. The opposite end portion of the bore is countersunk at <NUM>.

To assemble this embodiment, a self-locking nut <NUM> is inserted into the hexagonal counterbore <NUM> of each bolt hole <NUM>. A shaft of a respective cap screw <NUM> is inserted through the bore of each securing portion <NUM> of the attachment bar <NUM>. The attachment bar <NUM> is placed on the outer surface of the body <NUM> such that each ridge <NUM> is received in a corresponding one of the recesses <NUM>. The shafts of the screws <NUM> are passed through the bolt holes <NUM> in the body <NUM> to come into threaded engagement with the nuts <NUM>. The bolts are tightened such that the mating surfaces of the securing portions <NUM> are clamped against the outer surface of the body <NUM>.

The presence of the ridges <NUM> and recesses <NUM> serve to locate the attachment bar <NUM> in the correct position on the body <NUM> and also prevents the attachment bar <NUM> being installed in the incorrect orientation. The length and diameter of the head of the screws <NUM> is selected such that if an attempt is made to fit the attachment bar <NUM> to the wrong surface of the body <NUM>, the head will not enter the counterbores <NUM> of the bolt holes <NUM>, and are not long enough to project from the attachment bar <NUM> so preventing the nuts <NUM> from being installed.

In the embodiment of <FIG>, the body <NUM> is the same as that in the embodiment of <FIG>, and similar nuts and screws <NUM> are also included. However, the retention component of this embodiment is a knot blocking plate <NUM>, shown in <FIG> and <FIG>.

The knot blocking plate <NUM> has a periphery of size and shape such that when it is placed on the body <NUM> it completely covers the bridge hole <NUM>. An inner surface of the knot blocking plate <NUM> has a projecting boss <NUM> surrounded by a flat mating surface. The boss <NUM> is a close fit within the bridge hole such that when the knot blocking plate <NUM> is placed onto the body <NUM>, the mating surface comes into contact with the outer surface of the body <NUM> and the boss <NUM> enters the bridge hole <NUM> to locate the knot blocking plate <NUM> in the correct position on the body <NUM>.

Two bolt holes <NUM> pass through the knot blocking plate <NUM>. An end portion of each bolt hole <NUM> adjacent to the outer surface is countersunk at <NUM>. A recess <NUM> surrounds each bolt hole <NUM> where it opens to the inner surface of the knot blocking plate <NUM>. As with the attachment bar <NUM> described above, the presence of the ridges <NUM> and recesses <NUM> serve to locate the knot blocking plate <NUM> in the correct position on the body <NUM> and also prevents the knot blocking plate <NUM> being installed in the incorrect orientation. The length and diameter of the head of the screws <NUM> is selected such that if an attempt is made to fit the knot blocking plate <NUM> to the wrong surface of the body <NUM>, the head will not enter the counterbores <NUM> of the bolt holes <NUM>, and are not long enough to project from the attachment bar <NUM> so preventing the nuts <NUM> from being installed.

The knot blocking plate <NUM> has a central rope aperture <NUM> that extends between the inner and outer surfaces. The rope aperture <NUM> is shaped as a rounded rectangle and dimensioned such that two lengths of rope that will be used to form the bridge can pass through it side-by-side with little space between the ropes and the material surrounding the rope aperture <NUM>. Adjacent to where it opens to the inner and outer surfaces of the knot blocking plate <NUM>, the rope aperture <NUM> is flared in order that it presents no sharp or small-radius edges to a rope passing through it.

The rope bridge on a harness that uses the forward connection arrangement shown in <FIG> is formed by passing two ropes through the rope aperture <NUM> of each knot blocking plate <NUM> and tying suitable stopper knots in the ropes to the outside of the knot blocking plates <NUM>, as shown in <FIG>.

Claim 1:
A harness for supporting a person working at height comprising a back (<NUM>), leg loops (<NUM>), two forward connection arrangements (<NUM>) and a flexible load-bearing member (<NUM>) that extends between the connection arrangements (<NUM>), the forward connection arrangements serving to transferring load from the back and the leg loops to the load-bearing member, wherein each forward connection arrangement comprises: a body (<NUM>) that is permanently connected to the harness, characterized by the body (<NUM>), having inner and outer surfaces,
and its periphery can be considered as defining a region of a plane through which, six holes pass, the body is symmetrical about an axis A that extends within the plane and that forms a long axis of the body (<NUM>), the body having a bridge hole (<NUM>) centred on the axis A, a first and a second webbing slot (<NUM>, <NUM>) are disposed to opposite sides of the axis A, an attachment hole (<NUM>) that extends symmetrically about the axis A to partially surround the bridge hole (<NUM>) and to extend to a second axial end of the body (<NUM>) and two bolt holes (<NUM>) of circular cross-section pass through the body, at an axial position that is approximately half way along the axial extent of the bridge hole, the forward connection arrangement further including a retention component (<NUM>) that can be removably and rigidly connected via the bolt holes to the body to removably secure the flexible load-bearing member (<NUM>) to the body (<NUM>).