GB2192660A - A kit of parts providing a structure detachably secured to an inclined roof - Google Patents

Abstract

A kit of parts is disclosed able to be assembled to provide an open frame work structure detachably secure to an inclined roof 10. Means 22 detachably secure the structure to an exposed rafter 11 of the roof. <IMAGE>

Description

SPECIFICATION A kit of parts providing a structure detachably secured to an inclined roof This invention concerns a kit of parts able to be assembled to provide an open frame work structure detachably secured to an inclined roof, which structure provides a platform to support a man and/or materials.

A known -way of providing a platform at or on an inclined roof is to assemble an open frame work structure from the ground up. This is relatively time consuming in terms of assembly because of the number of components and, for the same reason, relatively expensive.

Also, the structure occupies a relatively large area of ground space which is often an inconvenience to the public.

The object of the invention is to provide a kit of parts able to be assembled to provide an open frame work structure which is capable of being secured to an inclined roof, is quick to assemble, has few parts and can be cheap.

The invention provides a kit of parts able to be assembled to provide an open frame work structure detachably secured to an inclined roof which structure provides a platform, wherein the structure has means for detachably securing it to an exposed rafter of the roof.

Such a -kit comprises few parts compared to the known way of providing a platform since it sits on the roof and is not built from the ground up. The parts can be transported up a ladder and the materials for working at the roof by means of a hoist. The connections of the parts to one another can be conventional but, because there are relatively few of them, the structure is relatively quick to assemble.

Preferably the structure is a prism in shape with generally right angled triangular ends, each triangular end comprising first second and third elongate members connected to one another, the first elongate member being the hypotenuse, the second elongate member extending generally horizontally and away from the roof and the third elongate member extending upwardly from the roof.

The means may comprise various types of clamp involving plates and bolts clamping the plates to the exposed rafter. Preferably, however, the means comprises a device having two generally parallel limbs which are spaced transversely~from and are connected to each other, one limb extending behind and the other limb extending in front of the rafter. The spacing of the limbs is greater than the thickness of the rafter and the device is simply pushed into place. The load of the rest of the structure when attached to the device will be downward on the limb in front of the rafter (exterior of the roof) causing it to try and pivot about the limb behind the rafter (interior of the roof) thereby locking the device in place.

To take account of differences in sizes of rafters on various roofs the spacing of the two limbs from each other is preferably adjustable and this may be achieved by connecting the limbs telescopically to each other.

To hold the device in place during assembly, the limb lying in front of the rafter may have a flange pivotally mounted thereon with holes for receiving nails.

Since the device will be inclined to the horizontal to prevent it slipping down, the structure preferably includes means detachably pivotally connecting the device to the second elongate member. Preferably, the means comprises an hook shaped element fixed to the second elongate member, which element engages a third limb of the device, the third limb extending generally parallel to the first two and being spaced from and in front of the rafter.

The second, elongate, generally horizontal member may, conveniently, be of a fixed length in which case the lengths of the other two members between the vertices of the triangular end would have to be adjustable to accommodate differing inclinations of roof.

Preferably the length of the first elongate member between the vertices of the traiangular end is adjustable so that going from a roof with a sharp incline to one with a shallower incline, the first elongate member does not protrude beyond the rest of the structure. Preferably, the first elongate member comprises a first elongate element fixed to a clamp and a second elongate element extending through the clamp, the clamp including means which engages the second elongate element with a wedging action to prevent it moving in one direction along its length relative to the clamp and allow it to move freely in the other direction along its length. The first elongate member may also comprise a third elongate element also fixed to the clamp, the second elongate element lying between the first and third elongate elements, and the wedging means may include a first movable wedging element.Preferably, the first movable wedging element is guided in rectilinear path converging with a second stationary wedging element and the second elongate element and the or each wedging element is a wheel or roller. So that orientation of the clamp does not affect its operation, the clamp may include resilient means urging the first movable wedging element to the position for clamping the second elongate element.

Preferably, the foot of the third elongate member has a pivotable base plate to accommodate different roof slopes.

An embodiment of the invention will now be described by way of example, reference being made to the accompanying drawings, of which: Figure 1 is a view showing one end of an open frame work structure detachably secured to an inclined roof; Figure 2 is a plan view, to an enlarged scale, of a device hooked on to an exposed rafter: Figure 3 is a side view of the device in position on the rafter after a second elongate member has been detachably pivotally connected to it; and Figure 4 is a plan view, to an enlarged scale, of part of the first elongate member with clamp.

Figure 1 shows an inclined tiled roof 10 of a house with a rafter 11 exposed. A structure is detachably secured to the roof 10. The structure 12 is an open frame work which is a prism in shape with generally right angled triangular ends, each end comprising first, second and third elongate members 12, 13 and 14 respectively connected to one another, the first member 12 being the hypotenuse of the triangle. The second elongate member or transom 13 extends horizontally and away from the roof 10 and the third elongate member or standard 14 extends upwardly from the roof.

The transom and standard or upright 13 and 14 are tubular aluminium poles connected to each other by a clamp 15. The foot of the standard 14 has a pivotable base plate 16 which is secured by nails to and sits on a board 17 which spreads the load and prevents the roof tiles from being damaged. The standard 14 extends upwardly past the level of the transom 13 and has a horizontal guard rail 18 fixed to it by a clamp 19, the guard rail extending along and being clamped to another standard of the structure.

The transom 13 supports three scaffold boards 20 so forming a platform, and a toe board 21. The transom 13 is detachably pivotally connected to a device 22 which is deta chably secured to the rafter 1 11. The device 22 comprises a rectangular metal tubular frame 23 with parallel first sides 24A and 24B and parallel second sides 25A and 25B.

Sides 24B and 25B are extended. An Lshaped metal bar 26 has one limb 27 extending into the extended side 25B and the other limb 28 lying parallel to the extended side 2413. The extended side 25B has a plurality of holes 29 and the limb 27 has a hole (not shown) so that the transverse spacing of the extended side 24B and the limb 28 can be telescopically adjusted and fixed by a pin 30 extending through one of the holes 29 and into the hole in the limb 27. The device 22 thus provides two generally parallel limbs 24B and 28, limb 28 extending behind and limb 24B extending in front of the rafter 11. The device 22 also has a flange 31 pivotally mounted on side 24B, which flange has holes for receivingnails temporarily to hold the device 22 in place during assembly.The end of the transom 13 opposite to that fixed by the clamp 15 to the upright 14 has fixed to it a hook shaped element 32. The element 32 has a spring loaded button 33 near the base so that as the element is pushed onto the limb or side 24A of the tubular frame 23 of the device 22, the button is pushed in then snaps out when the element fully engages the tubular side 24A, so locking the transom 13 to the decide 22. The limb 24A is higher than the limb 24B, which in turn is higher than limb 28, to ensure that when a downward load is applied to limb 24A, the device 22 does not slip.

The first elongate member 12 comprises two generally parallel metal rods 34 secured at one end by a removable pin to a tab 35 welded to the transom 13. The other end of the rods 34 are fixed to a clamp 36. A third rod 37 is secured at one end by a removable pin to a tab 38 welded to a collar 39 at the foot of the upright 14. The clamp 36 has an aperture through which the rod 37 extends and lies between the two rods 34. The clamp 36 also has one wheel or roller 40 guided in a rectilinear path 41 which converges with the rod 37 and a second wheel or roller 42 which is held in place in the clamp 36. When the rollers 40 and 42 are almost at the position where they are closest to each other, they engage the rod 37.When the roller 40 is urged to that position by gravity or some resilient means such as a coiled spring (not shown), the rod 37 can move freely in the direction from the tab 38 to the tab 35 relative to the clamp 36 but a wedging action takes place with movement in the opposite direction and the rod 37 is clamped fast.

When the first elongate member 12 is to be lengthened, the roller 40 is pushed back along its path 41 so that it disengages from the rod 37, and the rod 37 is then pulled through the clamp 36. When the structure is being assembled, the length of the first elongate member 12 is adiusted so that it is in tension and helps maintain the standard 14 upright. Tensioning of the elongate member 12 is effected by drawing the rod 37 through the clamp 36 in the direction from the tab 38 to the tab 35 and/or moving the clamp 36 over the rod 37 in the opposite direction.

In practice, the structure will have at least one diagonal brace (not shown) extending from the base of one upright 14 to the top of another upright.

For most cases, the transom 13 will be of fixed length since, according to accepted regulation there will be three, four or five scaffold boards 20 forming the platform, with a recommonded width of four boards. However, advantage can be gained by having a telescopically adjustable transom 13, for example, so as to make it smaller for storage and transport.

The device 22 can be modified by having a swing arm pivotally connected to limb 24B to lock onto limb 28 when the device is in place.

This is an added safety measure to preclude any possibility of the device from slipping sideways out of place.

In certain circumstances, the device 22 can be replaced by some form of clamp involving a plate secured in place on the rafter by bolts and having an upstanding projection for engagement by the hook 32 on the end of the transom 13.

Claims (16)

1. A kit of parts able to be assembled to provide an open frame work structure detachable secured to an inclined roof which structure provides a platform, wherein the structure has means for detachably securing it to an exposed rafter of the roof.

2. A kit of parts as claimed in Claim 1, wherein the structure is a prism in shape with generally right angled triangular ends, each triangular end comprising first, second and third elongate members connected to one another, the first elongate member being the hypotenuse, the second elongate member extending generally horizontally and away from the roof and the third elongate member extending upwardly from the roof.

3. A kit of parts as claimed in Claim 1 or 2, wherein the means comprises a device having two generally parallel limbs which are spaced transversely from and are connected to each other, one limb extending behind and the other limb extending in front of the rafter.

4. A kit of parts as claimed in Claim 3, wherein the- transverse spacing of the two limbs from each other is adjustable.

5. A kit of parts as claimed in Claim 4, wherein the limbs are connected teiescopically to each other.

6. A kit of parts as claimed in Claim 3, 4 or 5, wherein the limb lying in front of the rafter has a flange pivotally mounted thereon with holes for receiving nails to hold the device in place during assembly.

7. A kit- of parts as claimed in Claim 3, 4, 5 or 6, wherein the structure includes means detachable pivotally connecting the device to the second elongate member.

8. A kit of parts as claimed in Claim 7 wherein the means comprises an hook shaped element fixed to the second elongate member, which element engages a third limb of the device, the third limb extending generally parallel to the first two and being spaced from and in front of the rafter.

9. A kit of parts as claimed in any one of Claims 2 to 8, wherein the length of the first elongate member between the vertices of the triangular ends is adjustable.

10. A kit of parts as claimed in Claim 9, wherein the first elongate member comprises a first elongate element fixed to a clamp and a second elongate element extending through the clamp, the clamp including -means which engages the second elongate element with a wedging action to prevent it moving in one direction along its length relative to the clamp and allow it to move freely in the other direction along its length.

11. A kit of parts as claimed in Claim 9, wherein the first elongate member also comprises a third elongate element also fixed to the clamp, the second elongate element lying between the first and third elongate elements, and the wedging means includes a first movable wedging element.

12. A kit of parts as claimed in Claim 11, wherein the first movable weging element is guided in rectilinear path converging with a second stationary wedging element and the second elongate element.

13. A kit of parts as claimed in Claim 10, 11 or 12, wherein the or each wedging element is a wheel or roller.

14. A kit of parts as claimed in any one of Claims 10 to 13, wherein the clamp include resilient means urging the first movable wedging element to the position for clamping the second elongate element.

15. A kit of parts as claimed in any one of Claims 2 to 14, wherein the foot of the third elongate member has a pivotable base plate.

16. A kit of parts able to be assembled to provide an open frame work structure for detachable securing to an inclined roof, which structure provides a platform, substantially as herein described with reference to and as shown in the accompanying drawings.