WO2002013909A1

WO2002013909A1 - Ground recoverable safety-rope anchor system

Info

Publication number: WO2002013909A1
Application number: PCT/CA2000/000923
Authority: WO
Inventors: John Victor Watt
Original assignee: John Victor Watt
Priority date: 2000-08-11
Filing date: 2000-08-11
Publication date: 2002-02-21
Also published as: AU2000266739A1

Abstract

A climbing-rope anchoring method, an anchor strap and a recovery system, and a recovery device are disclosed. The anchoring system, suited to both running line and static line rappelling, is ground recoverable. An anchor strap, with end-rings, is used to girdle a suitable anchor, for example, a tree fork. A rope, to which rope-end-stops are affixed, is threaded through the anchor strap end-rings and a running collar retrieval device is attached to the rope between the two end-rings. The anchor system supports the weight of a climber during a rappel activity, upon reaching the ground, the climber pulls downward on one lead of the rope until a rope stop passes through an anchor strap end-ring and jams in the recovery device which then jams against the other end-ring. This frees one end of the anchor strap allowing it to be pulled from the anchor and fall to the ground.

Description

GROUND RECOVERABLE SAFETY-ROPE ANCHOR SYSTEM

TECHNICAL FIELD

The present invention pertains in general to industrial safety equipment and more particularly to an improved method and associated devices for anchoring safety ropes and climbing ropes particularly those required of industrial, tree-climbing activities. The invention provides a safety rope anchor method and an associated system and device which leads to improved safety, reduced wear on climbing ropes and in the case of commercial or industrial climbers, increased productivity. The anchor system offers the additional benefit of being recoverable, in its entirety, from the ground and is suited to both running rope (running line) and static rope (static line) rappelling.

BACKGROUND ART

In the majority of climbing activities, both recreational and industrial, upon completion of the climb and any associated tasks, the climber returns to the elevation at which the climb commenced by employing a practice known as rappelling. Rappelling is a technique by which a person can, by use of a safety rope, lower themselves manually, in a controlled fashion, from a position of height to a lower position. Rappelling involves the passing of a safety rope through or around a belay anchor point or belay device;, the climber then uses the rope to lower themselves to the extent allowed by the length of the rope. This practise is repeated until the person has reached the elevation which they are seeking. In the case of a static rope rappel, the rope is passed through the belay point up to the halfway mark and the climber descends passing the doubled rope through a descender device attached to the climber's climbing harness. In the case of a rappel using a running rope, the rope is passed through the belay point after which one end is tied off at the climber's climbing harness. The climber then controls his descent by regulating the speed at which the long end of the rope slides through a descender device.

It is common practice for recreational climbers, examples being mountain climbers, ice climbers and rock climbers, to rappel using a static rope together with a descender device appropriate to the task. Unlike the static rope technique common to recreational climbers, many industrial climbers, examples of these being Registered Forestry Climbers, Certified Arborists and Residential Tree Services Climbers, are constrained by training, safety requirements and work practice demands, to rappel using a running rope.

The majority of prior art, which is applicable to rappelling on a static rope and therefore meets many of the requirements of the recreational climber and those of some industrial climbers, does not provide a fully retrievable, robust anchoring method suited to use on a running rope. Accordingly there is a need for an improved anchoring method, an appropriate anchoring system and a suitable anchor retrieval device. Prior art applicable to rappelling on a running rope generally meets the work requirements of many types of industrial climber but presents a number of inefficiencies and significant safety concerns which can be addressed through improvements in the art. The current techniques for anchoring or belaying a Climbing Rope, in the course of this type of industrial climbing are indicated in Figure 1. The prior art is such that the Climbing Rope is wrapped around a tree trunk, with a portion of a branch (which in the jargon of the professional tree climbing trade is known as a 'nub' - refer to Fig. 1 (a)) to secure the Climbing Rope and keep it from sliding down the trunk, or, in other cases, it may be wrapped around a tree branch - refer to fig. 1 (b). The rope is then used for the running rope rappel which results in the rope being drawn over the 'nub; or the branch as the Climber rappels. This technique can lend itself to very high friction effects between the rope and the tree. These friction effects result in high wear on the Climbing Rope and increase, very dramatically, the workload associated with the recovery of the rope. Further, in the case of the 'nub', it can result in a severe safety hazard in which the Climbing Rope might track or run up and over the 'nub' resulting in the rope releasing from the belay anchor point, the result of which is the Climber sustaining a fall.

A search determined that there exists prior art related to climbing and safety devices such as descenders, ascenders, lowering devices, and rope climbing devices. Very little prior art related to rope belay point devices, rope belay devices or retrieval thereof was found. The search did not disclose any patents that read directly on the claims of the instant invention, however the following patents are considered related:

1. Rope Belay Fixture - Patent No.: Des. 288,722 (Mar. 17, 1987)

- U.S. Application No. 585,830 This patent describes a permanent, rope belay device for attachment to buildings.

2. Portable Tree Swing System - U.S. Patent No.: 5,704,669

This patent describes a system for installing and de-installing (retrieval), entirely from ground elevation, a swing over a tree branch.

3. Device used in the retrieval of climbing equipment - U.S. Patent No.: U.S. 5873613 (Feb. 23, 1997)

This patent describes a device for retrieving nylon rock-climbing slings which have been passed through a permanent, belay anchor ring. The technique defined in the associated disclosure utilizes the rope as a means of retrieving equipment specific to the following:

- a flexible, tapered, rope-end device, intended as a device for the recovery of a nylon webbing climbing-sling on which one of the loop ends has been reduced in effective inside dimension by application of an elastic band, is claimed;

- the use of a nylon webbing sling having sling loops through which the rope is intended to pass suited only to static rope rappelling;

- supports retrieval of an anchor sling leaving the belay anchor ring behind;

- retrieval is carried out from one specific end of the rope. SUMMARY OF THE INVENTION

In the drawings which form a part of this specification;

Figure 1. includes two views, fig. 1 (a) and fig. 1(b), which describe 'prior art'. This indicates two rope anchoring methods currently employed to carry out the tasks associated with industrial climbing which involve running rope, rappelling activities.

Figure 2. is a view of a recoverable, safety-rope anchor system, according to one embodiment of the invention, showing an anchor strap (1) en-circling a tree (B) trunk or tree (B) branch, a climbing rope (3), with rope-end-stops (4) at each rope end, passing through the two anchor strap end-rings (6), and a running collar retrieval device (2) attached to the climbing rope at a point between the two anchor strap end rings (6).

Figure 3. provides two views according to one embodiment of the invention. The view, fig. 3 (a), shows a view, according to one embodiment of the invention, of an anchor strap with end- rings (1). The view, fig. 3 (b), shows a view, according to one embodiment of the invention, of a running collar retrieval device (2).

Figure 4. provides two views, 4(a) and 4(b), of the rope-end-stop (4) according to one embodiment of the invention .

Figure 5. includes two views, fig. 5 (a) and fig.5 (b), which describe two rope belay methods, according to one embodiment of the invention, recommended for use in anchoring as required to carry out the tasks associated with industrial climbing which involve running rope rappelling activities.

DETAILED DESCRIPTION OF THE INVENTION

In the particular embodiment of the invention illustrated, Figure 2, Figure 3, Figure 4 and Figure 5, the anchor strap (1) is comprised of a strap (5) constructed of a robust, high strength, man- made fibre webbing with sewn loops (7) through which end-rings (6) are installed. The anchor strap (1) is intended to encircle a natural or man-made belay anchor, that being a tree trunk (B), a tree branch (B), a cross member on a steel tower, a rock, or similar natural or man-made anchor. The end-rings (6) are intended to support and to pass the climbing rope (3) used by the climber to rappel down from an elevated position. After the climber has installed the anchor strap around an appropriate anchor and has passed the climbing rope, to which rope- end-stops (4) have been attached, through the end-rings, the running collar retrieval device (2) is attached to the climbing rope at a point between the two anchor strap end-rings. The running collar retrieval device is comprised of a strap (10) to which a closable fastener (8), in this embodiment a small, carbiner device, and a ring (9), in this embodiment a ring having an outside diameter larger than the inside diameter of the two anchor strap end-rings, are attached in sewn or riveted loops (11). The climber proceeds to affix the rope to a descender device or a descender knot and then to rappel downward either to the extent required or to that possible given the length of the rope. Upon reaching the end of the rappel, the climber retrieves the system by hauling in on either end of the rope until such time as the rppe is pulled through either of the anchor strap end-rings to the point at which the rope-end-stop reaches the first anchor strap end-ring that it encounters. At this point, as the climber continues to recover the climbing rope, the rope-end-stop, which, having an outside diameter smaller than the inside diameter of the anchor strap end rings, passes through the first of the anchor strap end-rings. The rope-end-stop then catches in the closable fastener (8) portion of the running collar retrieval device (2) and draws the closable fastener through the second anchor strap end-ring at which point the ring (9), because it has an outside diameter smaller than the inside diameter of the anchor strap end-rings, becomes wedged in the second anchor strap end-ring. One end of the anchor strap assembly is free, the other end of the anchor strap assembly is 'attached' to the climbing rope by virtue of the recovery system. The climber continues to recover the climbing rope which in turn pulls the anchor strap assembly from the tree. The climbing rope, the running collar retrieval device and anchor strap assembly are then free to fall from the anchor position to the ground for retrieval by the climber.

It will be apparent that various changes and modifications can be made to components of the described system without departing from the scope of the invention as defined in the claims. Thus:

(a) the high strength, man-made fibre webbing with sewn loops could be replaced with rope, chain or wire rope with clamped or tied loops to secure the end-rings.

(b) the end-rings indicated in this embodiment of the invention are round rings, other ring types which are equally suited to the purpose include D-rings, V-rings, oval rings, U-bolts, U-rings and wire rope rings.

(c) the closable fastener described in the preferred embodiment of the invention is one component part of the defined running collar retrieval device. The closable fastener could be replaced by various metal or plastic snaps, spring clip devices or openable links which in every case could be of a predetermined size such that, unlike in the case of the preferred embodiment, the outside dimension of the closable fastener was such that the closable fastener would not pass through the anchor strap end-ring which would remove the requirement for the ring component part of the described running collar retrieval device.

Claims

THE EMBODIMENTS OF THE INVENTION IN WHICH AN EXCLUSIVE PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:

1. A method for the attachment of a safety rope or climbing rope and an anchor assembly to a secure, elevated, vertical or off-vertical or horizontal, anchor structure and for the retrieval of said rope and said anchor assembly remotely from the ground, comprising the steps of:

(a) placing an anchor strap around, through or over said elevated anchor structure;

(b) threading one end of said rope through both end-rings of said anchor strap results in an anchored rope suitable for rappelling;

(c) attaching a running collar retrieval device to that portion of said rope which lies in between said two end-rings of said anchor strap completes the attachment of said rope, said anchor strap and said running collar retrieval device;

(d) using said rope to rappel to the ground or to some appropriate intermediate position;

(e) pulling downward on one end of said rope to recover said rope causes said rope to slide through one said end-ring of said anchor strap, through said running collar retrieval device, and through the second said end-ring of said anchor strap until a rope-end-stop device, which is attached to the end of said rope, passes through one said end-ring, lodges in said running collar retrieval device which in turn lodges in said other end-ring; pulling downward on said rope to which only one end of said anchor strap remains attached leads to the recovery of said rope and said anchor assembly in their entirety.

2. The method according to claim 1 further including a method by which said rope-end-stop device attached to end of said rope is of a predetermined, outside dimension to permit said rope-end-stop device to pass through end-rings of said anchor strap but to not permit said rope-end-stop device to pass through said running collar retrieval device.

3. The method according to claim 1 further including a method by which said running collar retrieval device is attached to said rope by means of a closable fastener which is of a predetermined, inside dimension to permit said rope to run smoothly through said closable fastener or said ring but to not permit said rope-end-stop device to pass through said running collar retrieval device.

4. The method according to claim 1 further including a method by which said running collar retrieval device is of a predetermined, outside dimension such that said running collar retrieval device cannot pass through said end-rings of said anchor strap.

5. A ground retrievable, safety rope and climbing rope belay anchor system comprising in combination:

(a) an anchor strap for encircling a suitable vertical, off-vertical, or horizontal anchor structure; said anchor strap with end-rings at each end having a predetermined inside dimension through which said rope and a rope-end-stop device readily pass but through which a running collar retrieval device will not pass; (b) said running collar retrieval device which is of a predetermined, outside dimension such that said running collar retrieval device cannot pass through said end-rings of said anchor strap and which said running collar retrieval device incorporates a closable fastener which is of a predetermined, inside dimension to permit said rope to run smoothly through said closable fastener but to not permit said rope-end- stop device to pass through said running collar retrieval device.

(c) said rope with said rope-end-stops attached each end; during retrieval said rope- end-stops will permit the capture of said retrieval device which in turn will capture said anchor strap.

6. A device according to claim 1 for the recovery of said anchor strap assembly from said elevated anchor structure, which incorporates said closable fastener which is of a predetermined, inside dimension to permit said rope to run smoothly through said closable fastener but to not permit said rope-end-stop device to pass through said running collar retrieval device; and which incorporates a component part which is of a predetermined, outside dimension such that said running collar retrieval device cannot pass through said end-rings of said anchor strap.