AU2005223872B2 - Improved roping device - Google Patents

Abstract

A roping device for operating on a rope includes a first body portion (11) providing an attachment means (34) at one end, the body portion (11) including a first plate (18) having a front face and a reverse face and a second plate (20) having a front face and a reverse face. The plates (18, 20) are oriented in different planes defining an acute angle between the intersection of those planes. A first rotatable sheave (12) is mounted on the front face of the second plate (20) rotatable about an axis which is substantially perpendicular to the second plate. The first sheave (12) has a groove defining a generally semi-circular rope guide path having a first end and a second end. The first end of the guide path opens onto the front face of the first plate, and the second end of the guide path opens onto the reverse face of the first plate (18). The front face of the first plate defines a generally straight guide path in the form of a channel 21 along which the rope passes prior to the generally semi-circular guide path. A braking means (24) is mounted on the front face of the first plate (18).

Description

Improved roping devices Field of the Invention The present invention relates to improved roping devices and in particular, to devices which are suitable for use by a person who wishes to safely descend a shear face of a building, cliff or the like. Background of the Invention If a person needs to descend from a height, by for example, climbing down a ladder, cliff face or the like, for safety reasons, it is often necessary for the person to be attached in someway to the ladder or to a convenient securing point, so that in the event that the person slips and falls, he or she will be prevented from falling to the ground. Clearly, any device for this purpose should preferably be as small and unobtrusive as possible, in use, to allow the user to make the decent without significant interference. Such roping devices are often used by workers such as window cleaners and other workers maintaining the exteriors of sky scrapers and the like. Any discussion of documents, acts, materials, devices, articles or the like which has been included in the present specification is solely for the purpose of providing a context for the present invention. It is not to be taken as an admission that any or all of these matters form part of the prior art base or were common general knowledge in the field relevant to the present invention as it existed before the priority date of each claim of this application. Summary of the Invention According to the present invention there is provided a roping device for use with a rope, said device comprising: a first plate having a front face and a reverse face; a first attachment point for attachment of one end of the rope; a first rotatable sheave mounted on the reverse face of the first plate, the front face of the first plate defining a generally straight guide path for an opposite and free end of the rope; a braking mechanism mounted on the front face of the first plate adjacent the guide path, the braking mechanism being arranged for selectively braking the free end of the rope; a second plate connected to the first plate and angularly offset at an acute angle relative to the first plate, the second plate having a second attachment point adjacent the braking mechanism and positioned generally toward the centre of the roping device wherein the rope is at the said one end attached to the first attachment point and in a block and tackle arrangement passes around the first sheave wherein the second attachment point generally 2 aligns vertically with the first sheave whereby loading of the roping device at the first and the second attachment points substantially balances the roping device. The device is typically used with a sheave block defining one or more sheaves. A second sheave, coaxial with the first sheave may be provided. In use, a rope is attached to the first attachment means on the roping device passes up and around a sheave of the sheave block and back to the roping device then passes along the path adjacent the braking mechanism. The sheave block includes attachment means for attaching a sheave block to a secure attachment point. A person descending from a height attaches themselves to the second attachment means on the roping device and being adjacent the braking mechanism of the rope can easily adjust and control the mechanism to control their decent without assistance from a second person. In a preferred embodiment the second attachment means is defined in a second plate which is oriented at an acute angle of about 20 to 250 to the first plate and in use lies beneath the fist sheave. The sheaves are preferably freely rotatable. Brief Description of the Drawings A specific embodiment of the present invention will now be described by way of example only and with reference to the accompanying drawings in which: Figure I shows a first roping device and associated sheave block; Figure Ia is a diagram of the roping device of Figure 1; 3 THIS PAGE IS INTENTIONALLY BLANK WO 2005/089873 PCT/AU2005/000385 4 Figure 2 is a side view of the roping device shown in Figure 1; Figure 3 shows a second embodiment of a roping device and sheave block for single person operation; Figure 4 shows an enlarged view of the roping device of Figure 3; 5 Figure 5 shows a side view of the roping device shown in Figure 4; and Figure 6 is an end view of the roping device of Figure 3. Detailed Description of a Preferred Embodiment Referring to the drawings, Figure 1 shows a first roping device generally 10 indicated at 10 comprising a body portion 11, a first rotatable sheave 12 (hidden and shown in dashed outline in Figure la). The body is generally elongate and has two distinct sections 14 and 16. Both body sections define a flat plate being first and second flat plates 18 and 20, respectively. As is best seen in Figure la, the lower part 14 of the roping device defines a part 15 of a guide path for a rope 5 including a generally U-shaped channel 21 which extends along one side of the plate 18. A braking mechanism 24 is mounted on the side of the plate which defines the channel and defines a curved braking surface 26 which is adapted to frictionally engage the rope 5. The surface 26 defines an array of small spikes (not illustrated in the drawings). The braking member 24 is biased in the 20 direction A into an engaged position in which a rope 5 passing along the guide path is wedged between the braking surface 26 and an opposing part of the U-shaped channel 21 preventing the rope from being pulled in the direction D. When a tension force is applied in the opposite direction C, the braking member 26 allows the rope to freely pass through the U-shaped channel 21. In a variant (not shown), the braking 25 mechanism 24 also includes a latch pivotally mounted on the braking member which can be moved against the biasing force into an open position into a fully retracted position. The device 10 includes first and second attachment points 34, 32 in the form of holes in the first and second plates, respectively. Hole 34 is intended to allow the user 30 to connect the device by way of a karabiner 1 to a rung of a ladder or other convenient fixing point. As shown in Figure 1 the other hole 32 can be used to connect one end of the rope 5 to the device 10 when it is being used as a part of a block and tackle arrangement as shown in Figure 1 of the drawings. As illustrated in Figure 2 in particular, the plate 18 lies in a plane which meets 35 the plate 20 at an acute angle of approximately 20-25". Because of this, the rope 5 passing around the sheave 12 can pass behind the part 14 of the roping device avoiding WO 2005/089873 PCT/AU2005/000385 5 contact with the front part of the roping device and preventing wear and tear on the rope. This arrangement also allows sheave 12 to be much smaller than what would otherwise be required to prevent abrasion of the rope 5 in use. The sheave is about 4.5cm in diameter which is narrower than the width of the plate 18 which is about 5 7.5cm. Figure 2 also shows two additional co-axial rotatable sheaves 13a and 13b located on the reverse face of the first plate 18 for use with a block an tackle arrangement to increase mechanical advantage. In a variant, one or two additional sheaves could instead be located behind the second plate 20. 10 As shown in Figure 1, the device 10 is used in conjunction with a sheave block 50 having first and second sheaves and which is attached by way of a karabiner 1 to the person or object being lowered. One end of the rope is attached to the attachment point 32 of the device. The rope extends down to the sheave block, around one sheave, back up to the device 10, around to the sheave 13a, passing behind the plate 20, around down 15 to the first sheave of the sheave block, up towards the roping device, around the sheave 13b, down to the sheave block 12 through the channel 21 and braking mechanism 24. The tail end of the rope should be free to feed into the device as the user descends. In Figure 1 tension t is applied to a length of string 37, pulling the braking mechanism out of engagement to allow the rope to freely run through the channel 21. 20 A second embodiment of a roping device 100 is shown in Figures 3 to 5. In contrast with the first roping device, this device can be operated by a single person. The roping device 100 is used in conjunction with a sheave block 102 having three rotatable sheaves. The sheave block 102 defines an attachment point 104 in the form of a hole which is attached by way of a karabiner 1 to a rung of a ladder or other secure 25 attachment point. Roping device 100 is shown in more detail in Figure 4. The device defines a front plate 106 which defines an attachment point 108 in the form of a hole at one end. The front plate defines a generally U-shaped channel 110 extending at a predetermined distance along a side edge 106a of the plate. The device includes a braking mechanism 30 24 which is identical to the braking mechanism described in relation to the first embodiment and will not be described in detail in relation to this embodiment. Bosses 114 and 115 help control the path of a rope 5 through the device and to contain the rope 5 in the channel 110. Two rotatable sheaves 116 and 118 are disposed behind the plate 106 for rotation about an axis which is perpendicular to the plate 106. A plate 120 is 35 disposed between the two sheaves. The upper end 120a of the plate, in use, defines an WO 2005/089873 PCT/AU2005/000385 6 attachment point 122 in the form of a hole which projects further than the attachment point 108 defined in the plate 106. A second attachment point 124 is defined at the base of the roping device in use. This is defined in a plate 126 which extends from the longitudinal edge 106a away 5 from the front plate at an acute angle to the same of approximately 20-25*. In this way, the attachment point defined at the lower end of the device in use, is located generally towards the centre of the roping device and this improves the balance and stability of the apparatus, in use. In use as shown in Figure 3 a worker attaches the attachment point 104 of the 10 sheave block 50 to a secure attachment point define on the building or the like which they are to descend. The roping device 100 is attached by way of a further karabiner to their harness. The worker can easily control the braking mechanism 24 to allow rope to pass through the guide channel 110 when descending. It will be appreciated by persons skilled in the art that numerous variations 15 and/or modifications may be made to the invention as shown in the specific embodiments without departing from the spirit or scope of the invention as broadly described. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive.

Claims (8)

1. A roping device for use with a rope, said device comprising: 5 a first plate having a front face and a reverse face; a first attachment point for attachment of one end of the rope; a first rotatable sheave mounted on the reverse face of the first plate, the front face of the first plate defining a generally straight guide path for an opposite and free end of the rope; 10 a braking mechanism mounted on the front face of the first plate adjacent the guide path, the braking mechanism being arranged for selectively braking the free end of the rope; a second plate connected to the first plate and angularly offset at an acute angle relative to the first plate, the second plate having a second attachment point adjacent the 15 braking mechanism and positioned generally toward the centre of the roping device wherein the rope is at the said one end attached to the first attachment point and in a block and tackle arrangement passes around the first sheave wherein the second attachment point generally aligns vertically with the first sheave whereby loading of the roping device at the first and the second attachment points substantially balances the roping device. 20

2. A roping device as claimed in claim I also comprising a third plate disposed parallel to and separated from the first plate with the first sheave mounted therebetween, the third plate having the first attachment point located at an opposite end of the device relative to the second attachment point. 25

3. A roping device as claimed in claim 2 wherein the third plate is connected to the second plate which is positioned intermediate the first and the third plates.

4. A roping device as claimed in claim 2 also comprising a second sheave mounted on a 30 reverse face of the third plate.

5. A roping device as claimed in claim I wherein the first attachment point is located on the first plate at an opposite end of the device relative to the second attachment point. SPEC-912501 doc 8

6. A roping device as claimed in any one of the preceding claims wherein the second plate is offset at the acute angle of about 20 to 250 to the first plate. 5

7. A roping device as claimed in any one of the preceding claims wherein the sheaves are freely rotatable.

8. A roping device substantially as herein described with reference to and as illustrated in 10 the accompanying drawings. 01lnae