GB2276197A

GB2276197A - Attachment device

Info

Publication number: GB2276197A
Application number: GB9405413A
Authority: GB
Inventors: Harry Stanley May
Original assignee: Northern Electric PLC
Current assignee: Northern Electric PLC
Priority date: 1993-03-18
Filing date: 1994-03-18
Publication date: 1994-09-21
Anticipated expiration: 2014-03-18
Also published as: GB9405413D0; GB9305632D0; GB2276197B

Abstract

For providing a temporary secure support, e.g. for a lineman working on an overhead line distribution pole, an attachment device is provided. This has a clamping head (12) that can be screwed to engage a structure. A support limb (14) projects from the head and provides anchorages (24, 26) for attachment of a safety line and/or a harness. The device may be mainly of aluminium alloy. <IMAGE>

Description

ATTACHMENT DEVICE The present invention relates to an attachment or anchorage device, and particularly to a safety attachment device for use by a worker on a tall structure such as an overhead line distribution pole.

There are many structures such as telegraph poles, lamp posts, overhead line distribution poles and pylons which support components that may require the attentions of workmen. But many such structures do not provide intrinsically safe locations for workers, or even appropriate places to which they can attach conventional safety devices such as work positioning and/or fall arrest systems. There is thus a need for a device that can be attached (e.g. temporarily) to a structure to provide an appropriate attachment/anchorage means for further components, e.g. a safety harness or safety line for a worker.

In one aspect the invention provides an attachment or anchorage device having a clamping head having clamping means; and an attachment portion which extends from the head, and has means for the connection of further components. The clamping head may have screw-clamping means. The attachment means may be an elongate arm having one or more attachment formations, e.g. through-holes.

In another aspect the invention provides a support structure assembly, having a support structure and, clamped to an upper region thereof, an attachment or anchorage device capable of supporting the weight of a man and/or securely arresting the fall of a man.

An embodiment of the invention will now be described in more detail with reference to the accompanying drawing, which is a schematic perspective view of an attachment/anchorage device.

The illustrated attachment device 10 has a clamping head 12 and an arm 14 which is fast with the head 12. The clamping head 12 has a solid body that is approximately Gshaped. Thus there is a first jaw portion 16, a body portion 18 which extends at right angles thereto; and a second jaw portion 20 which extends at an acute angle to the body portion 18. The second jaw portion 20 has a bore with a threaded steel insert, through which a threaded jaw member 22 extends. This can be screwed upwardly to contact the angle region 23 between the first jaw portion 16 and the body portion 18, thus defining an enclosed space, or to clamp a portion of a structure against the first face portion 16 and body portion 18. This configuration enables the clamping head to lock securely to different' structural components. The clamp head 12 may be made of aluminium alloy.It may be solid, or a welded assembly. The threaded member 22 may be of steel. The arm 14 may also be of aluminium alloy and may be formed integrally with the head 12. It is an elongate hollow bar of square section, with a first pair of major faces parallel with the major faces of the clamp head 12. A major opening 24 passes through the arm 14, opening in the first pair of major faces. It has rounded or chamfered mouths 25 so that webbing straps passed through the hole will not be abraded.

A similar opening 26 extends through the arm at right angles to the first opening 24, and opens in the other pair of faces. Both openings are remote from the clamping head 12. The openings 24,26 provide locations for the attachment of further elements, e.g. associated with safety lines or safety harnesses.

The illustrated device is quite large, e.g. of length 60cm to 120cm. Being made primarily of aluminium alloy it can nevertheless be quite light, though strong. The clamp head 12 is designed to attach to a pole cross-arm or to an angle or channel section of a structure.

The device will generally be intended to be capable of withstanding a shock substantially greater than would be caused by an accident when the clamp head is clamped to a structure and a worker who is connected by some safety means to the arm falls from the structure, relying on the device for security. This means, of course, that the clamping arrangement must be suitably strong and reliable, and the general mechanical strength of the device must be adequate. In fact, the arm may be designed to operate either within or outside its elastic limit. In the latter case, it could serve to cushion an arresting force.

A device generally as shown may also be used for the coupling of lifting equipment to a structure.

Claims

1. An attachment device capable of temporary connection to a structure to support, or arrest the fall of, a worker; said device having a clamping head with clamping means; and an attachment portion which extends from the head, and has means for the connection of further components.

2. A device according to claim 1 wherein the clamping head has screw-clamping means.

3. A device according to claim 1 wherein the clamping head has first and second clamping surfaces extending at an angle from a corner region; a limb extending from the second surface remote from the corner region; and a mobile jaw having a shaft extending through an opening in the limb, the shaft being displaceable to move the jaw towards and away from the corner region.

4. A device according to claim 3 wherein the limb and shaft are threadedly engaged.

5. An attachment device according to any preceding claim having a safety harness or safety line for a worker coupled to the attachment portion.

6. A device according to any preceding claim wherein the attachment portion is an elongate arm.

7. A device according to claim 6 wherein the arm has one or more through-holes in a region remote from the head.

8. A device according to claim 7 having two throughholes extending transversely through the arm at angles to one another.

9. A device according to claim 6, 7, or 8 which is at least 30cm long.

10. A device according to any preceding claim made substantially of aluminium alloy.

11. An attachment device substantially as herein described with reference to and as illustrated in the attached drawing.

12. A support structure assembly having a support structure and, removably attached to an upper region thereof, an attachment device according to any preceding claim.