GB2556865A

GB2556865A - Descender for a rope

Info

Publication number: GB2556865A
Application number: GB1614859.5A
Authority: GB
Inventors: Mark Edmondson Christopher; Thomas Sewell George
Original assignee: Heightec Group Ltd
Current assignee: Heightec Group Ltd
Priority date: 2016-09-01
Filing date: 2016-09-01
Publication date: 2018-06-13
Also published as: GB201614859D0

Abstract

A descender comprising a locking means with a first engaging member 5 movable between a release position and a jamming position such that rope 7 is trapped between the engaging member 5 and an adjacent abutment 2 when a load is applied to a downstream end 19 of the rope. The locking means also comprises a second engaging member 6 which is urged from a release position to a rope jamming position trapping rope 7between the second engaging member 6 and an another abutment 3 when a load is applied to an upstream end 20 of the rope. This configuration ensures that if the rope is incorrectly threaded into the device backwards, the pulley is still urged into a rope jamming position when the rope is pulled from either end. The descender further comprises rope guide means 13 and attachment means 9, 12 for attaching the descender to another rope or person or object. First 5 and second 6 engaging means may be mounted on a first supporting plate 8. A second cover plate 11 may be pivotally mounted to move between a rope loading/unloading position and a closed position. There may be a control handle 10.

Description

(54) Title ofthe Invention: Descender for a rope

Abstract Title: Descender which functions if rope is threaded a wrong direction into the descender.

(57) A descender comprising a locking means with a first engaging member 5 movable between a release position and a jamming position such that rope 7 is trapped between the engaging member 5 and an adjacent abutment 2 when a load is applied to a downstream end 19 ofthe rope. The locking means also comprises a second engaging member 6 which is urged from a release position to a rope jamming position trapping rope 7between the second engaging member 6 and an another abutment 3 when a load is applied to an upstream end 20 ofthe rope. This configuration ensures that if the rope is incorrectly threaded into the device backwards, the pulley is still urged into a rope jamming position when the rope is pulled from either end. The descender further comprises rope guide means 13 and attachment means 9, 12 for attaching the descender to another rope or person or object. First 5 and second 6 engaging means may be mounted on a first supporting plate 8. A second cover plate 11 may be pivotally mounted to move between a rope loading/unloading position and a closed position. There may be a control handle 10.

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Figure 1

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Figure 3

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Figure 4

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Figure 5

Descender

The invention relates to a descender for a rope.

Self-locking descenders for abseiling along a rope are known. Self-locking descenders are characterised in that when the user lets go of the descent control mechanism the descender grips the rope and either slows the descent or brings it to a stop to prevent the user from falling or descending out of control. Further, some descenders also stop if over operated in panic. Again, this stops the user from falling or descending out of control. When the rope is threaded into a descender device it can be loaded in either of 2 directions i.e. from either end. If the correct end of the rope is loaded the locking mechanism of the descender, usually a rotating cam, will be urged into the lock position gripping the rope and slowing or stopping the descent. However, if the rope is loaded at the wrong end, e.g. by threading the rope into the descender backwards, the locking mechanism will be urged away from the locking position and therefore not grip the rope causing the user to fall or descend out of control.

Some descenders try to protect against this risk by guiding the rope through the descender in a specific path. The amount of protection provided by this is minimal as it is still possible to load the wrong end of the rope. One particular device employs an additional mechanism to block the passage of the rope. This mechanism adds extra parts and therefore size, weight, complexity and cost to the descender. Additionally, the rope will only engage with the mechanism when it is in the correct orientation. As such, in certain orientations, gravity will hold the rope away from the mechanism or alternatively the user may inadvertently hold the rope away from the mechanism preventing it from functioning.

The current invention seeks to overcome this problem by engaging the rope to slow/control or stop the descent whichever end of the rope is loaded.

According to the present invention there is provided a descender for controlling the lowering and/or raising of a load on a rope, the descender comprising rope guide means for guiding and controlling the passage of a rope through the descender and attachment means for attaching the descender to a further rope and/or an object/person to be lowered and/or raised, the rope guide means includes locking means comprising a first engaging member moveable between a rope jamming position wherein the rope is trapped between the engaging member and an adjacent abutment and a release position wherein the engaging member is spaced from said abutment, the rope guide means being arranged such that the first engaging member is urged towards its rope jamming position when a load is applied to a downstream end of the rope, the first engaging member being selectively moveable towards its release position in order to selectively control the movement of the rope through the rope guide means, wherein should the load be applied to the upstream end ofthe rope a second engaging member is urged from a release position towards another adjacent abutment and into a second rope jamming position.

Preferably both the first and second engaging means are provided on the same component.

Preferably the second engaging member may be selectively held in the release position such that the rope may be paid in or out of the descender freely.

Preferably, when the second engaging member is held in the release position it may be released such that it may move towards the rope jamming position when the load applied to it exceeds a predetermined threshold.

Preferably the second engaging member is selectively movable to the second rope jamming position.

An embodiment of the present invention will now be described by way of example only and with reference to the accompanying drawings in which:

Figure 1 is front view of the invention with the cover plate in the rope loading/unloading position and the first and second rope engaging members in the release position.

Figure 2 is a front view of the invention with the cover plate removed, the first rope engaging member in the rope jamming position and the second rope engaging member in the release position.

Figure 3 is a front view of the invention with the cover plate removed, the first rope engaging member in the release position and the second rope engaging member in the rope jamming position.

Figure 4 is rear view of the invention.

Figure 5 is a rear view of the invention with the control handle in the pre-set position whereby the second rope engaging means are prevented from reaching the rope jamming position.

A preferred embodiment of the invention comprises a predominantly circular pulley 1 mounted eccentrically with relation to its centre on a spindle 4 secured normally on a flat portion of supporting plate 8. A second supporting or cover plate 11 is mounted substantially parallel to the first supporting plate 8, the second supporting plate 11 being pivotally movable between a rope loading/unloading position and a closed position to allow rope 7 to be inserted and then retained in the device. The outer circumferential surface of the first pulley 1 is, in places, provided with a groove to retain the rope around the circumferential surface of the pulley.

An aperture 9 corresponds with a similar aperture 12 in the second supporting plate 11 to allow a connector, such as a karabiner or screw link, to be inserted to connect the device to a person or a secure anchorage point.

A first abutment member 2 is mounted normally on the first supporting plate 8 adjacent to the pulley 1. A second abutment member 3 is mounted on the first supporting plate 8 adjacent to the pulley 1 and first abutment member 2. Said pulley 1 and first and second abutment members 2, 3 are mounted on plate 8 together with additional rope guide means 13 such that they define between them a substantially u-shaped path with the rope 7 passing there around.

A control handle 10 comprising a substantially elongate flat plate is pivotally mounted on said spindle 4 on the opposite side of first supporting plate 8 to pulley 1. First supporting plate 8 contains an aperture 14 with a pulley operating member 16 securedly affixed to pulley 1 protruding therethrough. Control handle 10 contains an aperture 15 corresponding with aperture 14 in first supporting plate 8. The ends of said aperture 15 engage with the pulley operating member 16 when the control handle 10 is rotated in either direction thus urging pulley 1 in the same direction.

Control handle aperture 15 is larger than support plate aperture 14 such that the limits of movement of pulley 1 are defined by pulley operating member 16 contacting the proximal or distal ends/portions of support plate aperture 14. As such it is possible that apertures 14, 15 may be aligned such that pulley 1 is free to move from the first rope engaging position to the second.

In use the second supporting plate 11 is moved to its rope loading/unloading position and a rope 7 is threaded anti-clockwise in a U-shape around the pulley 1, moving away from the downstream end 19 of the rope 7 (i.e. the end of the rope to which the load is to be applied).

The rope 7 passes additional rope guide means 13, second abutment member 3 and first abutment member 2 before leaving the device.

When a load is applied to a downstream end 19 of the rope 7, the frictional force created by the rope 7 around the pulley 1 will cause the pulley 1 to pivot in a clockwise direction, thus locking rope 7 securely between point surfaces on the first rope engaging member 5 of pulley 1 and first abutment member 2.

In order to release the rope 7 the control handle 10 is rotated in an anti-clockwise direction, moving the pulley 1 in an anti-clockwise direction and allowing the rope to move through the device.

Further anti-clockwise rotation of the control handle moves the second rope engaging member 6 of pulley 1 towards second abutment member 3 clamping the rope securely therebetween. Thus allowing the device to brake the rope to a complete halt if the control handle is operated in panic or the user tries to descend at too greater speed.

If a load is applied to an upstream end 20 of the rope 7, the frictional force created by the rope 7 around the pulley 1 will cause the pulley 1 to pivot in an anti-clockwise direction, thus locking rope 7 securely between point surfaces on the second rope engaging member 6 of pulley 1 and second abutment member 3.

Sprung loaded handle engaging means 17 are mounted on first support plate 5. Said engaging means 17 allow control handle 10 to be rotated to and held in a pre-set position until the force applied to control handle 10 exceeds a predetermined threshold. The pre-set position being that where the aperture 15 prevents the second rope engaging means 6 of pulley 1 from reaching the rope jamming position.

Preferably the predetermined threshold force of the handle engaging means 17 is below the frictional force created by the rope 7 around pulley 1 such that the force on pulley 1 will push the handle from its pre-set position allowing the second rope engaging means 6 of pulley 1 to reaching the rope jamming position. Rope guide 13 ensures that the rope 7 has sufficient contact with pulley 1 to provide the level of friction required.

In an alternative embodiment, not shown, the two abutment members 2, 3 may be provided in one component. Additionally, the surface of either or both abutment members may be grooved to provide additional grip on the rope.

Claims

1. A descender for controlling the lowering and/or raising of a load on a rope, the descender comprising rope guide means for guiding and controlling the passage of a rope through the descender and attachment means for attaching the descender to a further rope and/or an object/person to be lowered and/or raised, the rope guide means includes locking means comprising a first engaging member moveable between a rope jamming position wherein the rope is trapped between the engaging member and an adjacent abutment and a release position wherein the engaging member is spaced from said abutment, the rope guide means being arranged such that the first engaging member is urged towards its rope jamming position when a load is applied to a downstream end of the rope, the first engaging member being selectively moveable towards its release position in order to selectively control the movement of the rope through the rope guide means, wherein should the load be applied to the upstream end of the rope a second engaging member is urged from a release position towards another adjacent abutment and into a second rope jamming position.

2. A device according to claim 1 wherein the second engaging member is selectively movable from its release position to the second rope jamming position.

3. A device according to any preceding claim wherein the second engaging member and its adjacent abutment are contained within the rope guide means such that the rope may not be held in a position out of contact therewith.

4. A device according to any preceding claim wherein the both the first and second engaging means are provided on the same component.

5. A device according to any preceding claim wherein the second engaging member may be selectively held in the release position such that the rope may be paid in or out of the descender freely.

6. A device according to claim 5 wherein, when the second engaging member is held in the release position it may be released, such that it may move towards the rope jamming position, when the load applied to it exceeds a predetermined threshold.

7. A device according to claim 6 wherein the second engaging member is held in the release position by virtue of pulley 1 having its movement restricted by the control handle which is itself held in a predetermined position.

8. A device according to claim 7 wherein the control handle is held in its predetermined position by sprung loaded engaging means.

9. A device according to claim 6 wherein the control handle comprises a substantially elongate flat plate.

10. A device according to claim 6 wherein the handle is selectively movable between 3 operating positions, where the handle restricts the movement of the pulley such that the second engaging member is held in the release position, where the handle is not in operative connection with the pulley and where the handle urges the pulley and so the first engaging means away from the rope jamming position and the second engaging means toward the rope jamming position.

11. A device according to claim 1 wherein the first and second rope engaging members are provided on a pulley pivotally mounted on a first plate adjacent to first and second abutment members.

12. A device according to claim 11 wherein the pulley has, in places, a groove to retain the rope around the circumferential surface.

13. A device according to claim 11 wherein the first and second abutments are substantially rectangular and mounted normally to the plate.

14. A device according to claim 13 wherein either or both of the abutments may have a grooved surface for increased grip against the rope.

15. A device according to any preceding claim wherein the second supporting plate is movable between a rope loading/unloading position and a closed position wherein the second plate covers at least the section between the first and second engaging means and the first and second abutment members.

16. A device according to any preceding claim wherein the attachment means comprise a first aperture in the first supporting plate which aligns with a similar aperture in the second supporting plate when in the closed position to allow a connector, such as a karabiner or screw link, to be inserted to connect the device to a person or a secure anchorage point.

17. A device substantially as herein described with reference to the accompanying drawings.

Ί

Ms Rachel Evans

21 March 2018

GB1614859.5

1-16