GB2394748A

GB2394748A - Securing ladder to scaffolding

Info

Publication number: GB2394748A
Application number: GB0404319A
Authority: GB
Inventors: Peter John Jones
Original assignee: PRESCO SCAFFOLDING Ltd
Current assignee: PRESCO SCAFFOLDING Ltd
Priority date: 2004-02-27
Filing date: 2004-02-27
Publication date: 2004-05-05
Also published as: GB0404319D0

Abstract

A fitting for securing a ladder 33 to a scaffolding pole 31 comprises a plate having at one end a cut-out adapted to engage the scaffolding pole, and to support clamp 37 which engages the pole as shown, and at the other end two hooks 23,24 on opposite sides of plate 12, each for engaging a stile of a ladder, the hooks being sized for the two most common widths "x" of stile encountered with metal ladders, so that the one fitting may be used to secure either of these types of ladder.

Description

- 1 - FITTING

This invention relates to a fitting which is particularly, but not exclusively, suitable for securing a ladder to scaffolding.

Fittings for securing ladders to scaffolding are known in the construction industry. Ladders used with scaffolding have traditionally been of wooden construction, having uprights or stiles of circular cross- section. One such known fitting for use with wooden ladders includes a portion such as a curved hook for fitting to the ladder upright and a clamp portion for fitting to a scaffolding pole. However, steel or aluminium ladders have become increasingly popular for use with scaffolding. Such steel or aluminium ladders generally have uprights of square or rectangular cross-section, and thus fittings having a curved portion for fitting to the ladder upright are not suited for use with such modern ladders. It is also known to secure ladders to scaffolding with wire lashings, but these however are time consuming to fit and to remove after use.

When designing a scaffolding fitting, it is necessary to consider the dimensions of the ladder portion to which the fitting is to be attached. For fittings which are to be fitted to an upright of a ladder, the distance from the front to the rear of a given ladder upright (hereinafter referred to as the upright depth') is critical. Having researched the market, the Applicants have found that steel or aluminium ladders presently used with scaffolding do not have a uniform upright depth. More specifically, they have found that 85 to 95% of such ladders have one of two 'standard' upright depths, the remaining 5 to 15% having a variety of upright depths. Future changes in

- 2- the ladder market are such that the proportion of ladders having one of two standard' upright depths is likely to increase. Thus it would be advantageous to provide a fitting that is suitable for use with each of these two standard ladder upright depths.

An object of the invention is to provide an improved fitting.

According to a first aspect of the invention, there is provided a fitting for securing a first structure to a second structure, said fitting comprising a body, and having a first end portion with a surface adapted to engage said first structure, and, at a position spaced from said first end portion, a first and second engagement means, wherein each of said first and second engagement means is adapted to engage said second structure, and wherein the distance between said first engagement means and said surface of said first end portion is less than the distance between said second engagement means and said surface of said first end portion.

Preferably, said first structure is a scaffolding pole, and desirably said second structure is an upright of a ladder.

Preferably, said body of the fitting comprises a plate having two opposing faces, and which advantageously is substantially flat.

Preferably, said first and second engagement means each comprise a base element extending outwardly from the body of the fitting in a substantially perpendicular direction therefrom, and a lip extending from said base element towards said first end portion in a direction substantially parallel to the plane

- 3 - of said body. Preferably, said first and second engagement means are located respectively on opposite faces of the body. Desirably, said second engagement means is formed by folding of a second end portion of the fitting. Advantageously, said first engagement means is welded to said second end of the fitting. Alternatively, said second end portion is provided with at least one cut so as to form at least two legs, wherein the said first and second engagement means are formed by folding said legs respectively towards opposite faces of the body. Preferably, two such cuts are provided, so as to form two outer legs and one inner leg. Desirably, the first engagement means comprises said outer legs which have each been folded towards one of said faces of said body, and the second engagement means comprises said inner leg which has been folded towards the opposite face of said body. Alternatively, the first engagement means comprises said inner leg which has been folded towards one of said faces of said body, and the second engagement means comprises said outer legs which have been folded towards said opposite face of said body.

Preferably, said first end portion of the fitting has an end profile containing a cut-out, for engagement with said first structure. Desirably, said cut-out is arcuate, for example substantially semi-circular.

Preferably, said first end portion of the fitting is provided with clamp means for securing said body to said first structure. Advantageously, said clamp means comprises an externally threaded rod, an internally threaded nut threadably engaged with said externally threaded rod, and an arm adapted to engage said first structure. Preferably, said externally threaded rod and said arm are each pivotably connected to said first end portion of the fitting.

- 4- Desirably, said first end portion of the fitting is provided with a first and a second aperture therethrough. Conveniently, said rod is fitted via a pin at said first aperture, and said arm is fitted via a pin at second aperture, such that said rod and arm may be pivoted about said respective apertures.

Advantageously, said arm has an aperture therethrough, such that, in use, when said arm is engaged against said first structure, said externally threaded rod is passed through said arm aperture and said internally threaded nut screwed onto the external threads of said rod is tightened to secure the fitting to said first structure.

Preferably, said fitting is formed from metal, and conveniently said fitting is formed from mild steel.

According to a second aspect of the invention, there is provided a fitting for securing a first structure to a second structure, said fitting comprising a body, and having a first end portion with a surface adapted to engage said first structure, and, at a position spaced from said first end portion, a first and second engagement means, wherein each of said first and second engagement means is adapted to engage said second structure, and wherein the distance between said first engagement means and said surface of said first end portion is less than the distance between said second engagement means and said surface of said first end portion, and said first end portion of the fitting is provided with clamp means for securing said body to said first structure.

According to a third aspect of the invention, a method of manufacture of a fitting comprises the steps of providing a plate having a first and a second opposing face and a first end portion with a surface adapted to engage a first

structure, cutting said plate so as to form at least two legs at a position spaced from said first end portion, folding at least one of said legs towards said first face, and folding at least a second of said legs towards said second face, such that each of said folded legs forms at least part of either a first or a second engagement means which is adapted to engage a second structure, wherein the distance between said first engagement means and said surface of said first end portion is less than the distance between said second engagement means and said surface of said first end portion.

Preferably, the plate is provided with one cut so as to form two legs, said cut extending from a free edge of the plate furthest from said first end portion, towards said first end portion. Advantageously, two such cuts are made, so as to form two outer legs and one inner leg. Desirably, said outer legs are folded to form said first engagement means, and said inner leg is folded to form said second engagement means. Alternatively, said outer legs are folded to form said second engagement means, and said inner leg is folded to form said first engagement means. Preferably, said method of manufacture further includes the step of cropping to the desired length the leg or legs which form said first engagement means.

The invention will now be described, by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a perspective view of a fitting of the invention, Figure 2 is an end view of the fitting of Figure 1,

- 6- Figure 3 is a side view of the fitting of Figures 1 and 2, and Figures 4 and 5 are respective fragmentary side perspective views of a pair of fittings of Figures 1 to 3 having clamp means attached, and fitted to a scaffolding pole and a ladder upright.

Referring to the drawings, a fitting 10 according to one aspect of the invention has a body portion 11 which is formed from a flat metal plate, preferably of mild steel, having two opposing faces 12, 13. The body 11, which is generally square or rectangular, has a first end portion 14, and a second end portion 15. The first end portion 14 has, at its free edge surface, an arcuate cut-out 16 defining an end edge surface 17. The cutout 16 is shaped for engagement with a first structure, and is substantially semi-

circular in the illustrated embodiment. However, it will be appreciated that the shape of the cut-out portion will be dependent on the shape of the first structure to which it is intended to be engaged. Two rounded projections 18, 19 are defined at either side of the cut-out 16, the projections having circular apertures 21, 22 respectively therethrough, the relevance of which will be discussed later.

At or adjacent the second end portion 15 of the body 11 are provided two separate engagement means in the form of hooks 23, 24 respectively, which are located on opposite faces, i.e. 12, 13 respectively of the body 11. Each hook comprises a base 25 and a lip 26. As will be seen best from Figures 1 and 2, the base 25 of each hook extends outwardly from the body 11, in a perpendicular direction therefrom, and is of rectangular profile. Each lip 26 extends normally from the free end of its associated base, in a direction

- 7- towards the first end portion 14 of the fitting. As can be seen from Figures 1 to 3, hook 23 is disposed nearer to first end portion 14 than is hook 24.

More specifically, in terms of distance from first end portion 14, hook 23 is separated from hook 24 by the height of lip 26. As can be best seen from Figures I and 2, hook 24 is integrally formed by folding the end of the plate forming the body 11, whilst hook 23 is attached to the body by any suitable method, for example by welding, to the face 12 of body 11. Figures 1 and 2 show a weld 27 joining the base 25 of hook 23 to face 12. It will be appreciated that hook 24 need not be formed by folding of the body 11, and may instead be attached to the body by any suitable means.

In an alternative embodiment (which has not been illustrated), both the first and the second engagement means 23, 24 respectively may be formed by folding of the body. In this case, the second end portion 15 of the body is provided with at least one cut so as to form at least two legs, each of said first and second engagement means being formed by folding the legs respectively towards opposite faces of the body. Each cut extends from the free edge of the second end portion 15 of the body 11, towards the first end portion 14. Preferably, two such cuts are provided, so as to form two outer legs and one inner leg, although it will be appreciated that only one such cut need be made, forming two legs, one of which is folded towards one face of the body to form one hook, the other folded towards the opposing face to form another hook. When two such cuts are made, the first engagement means may comprise the two outer legs which have each been folded towards one of said faces of said body, i.e. comprises two spaced apart hooks, whilst the second engagement means comprises the inner leg which has been folded towards the opposite face of said body to form a single hook. Alternatively,

- 8- the first engagement means may comprise the inner leg which has been folded towards one face of said body to form a single hook, whilst the second engagement means comprises the two outer legs which have been folded towards the opposite face of the body to form two spaced apart hooks. It is envisaged that more than two cuts may be provided in the body, and the resultant legs folded into hooks towards either face of the body as desired.

A fitting 10 of the invention is used to secure a first structure to a second structure. In the embodiment as illustrated and described herein, the first structure is a scaffolding pole 31, and the second structure is an upright of a metal ladder 32. Figure 4 shows the fitting 10, securing the ladder 32 to the pole 31. As can be seen from Figure 4, the ladder 32 has two stiles or uprights 33, between which run a series of horizontal steps 34. Each upright 33 is of rectangular cross-section, having opposing front and rear faces 35, and opposing inner and outer faces 36. Arrowed line x denotes the distance between front and rear faces of each upright, this distance being referred to herein as the 'upright depth'. Figure 5 shows the fitting 10 fitted to a pole 31 and ladder 32'. Ladder 32' has different dimensions to that of ladder 32, and for ease of reference, it will be appreciated that those reference numerals used to identify the components of ladder 32' will be equivalent to those used to denote the components of ladder 32, but having a dashed (') suffix. The upright depth x of ladder 32 is larger than upright depth x' of ladder 32'.

Ladders 32 and 32' represent the two types of ladder referred to in the introduction as having one of two 'standard' upright depths, which constitute

85 to 95 % of modern steel or aluminium ladders.

- 9 - The fitting 10 is provided with means for securing the body 11 of the fitting to the pole 31. Any suitable fixing means may be used, although in the illustrated embodiment, as can be seen in Figures 4 and 5, clamp means 37 are used. These particular clamp means have been previously designed by the Applicants, and are known to be used in the construction industry as scaffolding clamps. As can be seen from Figures 4 and 5, the means 37 comprises an arm 38, the inner surface of which is adapted to engage the pole 31, an externally threaded rod 39, and an internally threaded nut 41 formed for threaded engagement with the external threads of rod 39. Arm 38 is provided with apertures at both of its ends, the relevance of which will be discussed later. The arm 38 and rod 39 of the clamp means 37 are pivotably attached to the first end portion 14 of the fitting 10 by respective fixing pins passing through the apertures 21, 22 respectively of the fitting, and through apertures (not shown) provided in the arm 38 and the rod 39. The pin through the arm is denoted by numeral 42. It will be noted that the location of arm 38 and rod 39 may be interchangeable, in that both may be attached to the fitting via either of apertures 21 or 22. In the preferred embodiment, the fitting 10 and clamp means 37 are formed from mild steel, although it will be appreciated that any suitable material may be used.

In use, the fitting 10 of the invention is fitted to each upright 33 of ladder 32, and each upright 33' of ladder 32' as shown in Figures 4 and 5 respectively.

For each fitting, either hook 23 or 24 is placed around the ladder upright 33' or 33 respectively, so that a hook base 25 abuts an upright face 35, and each upright side 36 or 36' (depending on which ladder is being used) is held between a fitting face 12 or 13, and lip 26. Either of fitting hooks 23 and 24 may be selected, depending on which of ladders 32 or 32' is to be secured to

- lo -

the scaffolding pole 31. In the illustrated embodiment, for each fitting 10, the hook 24 is formed such that the distance between the innermost portion of the cut-out profile 16 and the hook base 25 corresponds to upright depth x of ladder 33, and the width of the base 25 of hook 24 corresponds to the width of the front and rear faces 35 of the ladder uprights 33. Similarly, hook 23 is formed such that the distance between the innermost portion of the cut-out profile 16 and the hook base 25 corresponds to upright depth x' of ladder 33', and the width of the base 25 of hook 23 corresponds to the width of the front and rear faces 35' of ladder uprights 33'. Thus hooks 24 will be selected for use with uprights 33 of ladder 32, and hooks 23 will be selected for use with uprights 33' of ladder 32'. It will be appreciated that when the fitting is secured to the ladder and pole, the pole abuts the front face of the ladder. The steps for securing a fitting 10 according to the invention to a ladder 32 and pole 31 will now be described with reference to Figure 4. It will be appreciated that hooks 24 may be engaged with either the front or rear aspect of the upright 33, depending on which is more convenient for the user.

However, the fitting will usually be secured to the front aspect of the ladder, so that the pole 31 does not present an obstruction to the user when ascending or descending the ladder. Once hook 24 has been placed against the upright 33 in the desired position along the upright, pole 31 is introduced at the first end portion of the fitting so that the surface 17 of cut-out portion 16 abuts the pole. The arm 38 of clamp means 37 is then pivoted so as to close around the pole. The rod 39 is then inserted into the available arm aperture (not shown) and the nut 41 threaded onto the rod is tightened so as to secure the fitting to the pole. The securement of the fitting 10 the upright 33' of ladder

- 11 32' is similar to that described above, with the exception that hook 23 is employed instead of hook 24. Thus it will be appreciated that the presence of two hooks 23, 24 allows a single fitting lo according to the invention to be used to secure ladders having two different upright depths, to a scaffolding pole. In order to facilitate a user choosing between hooks 23 and 24, some fittings may be provided with the arm 38 of clamp means 37 pivotably attached via aperture 22 and rod via aperture 21, with other fittings having the arm 38 attached via aperture 21 and the rod via aperture 22, i.e. the fittings are handed' with respect to the clamp means orientation. When the fittings are provided with alternative 'handing' as in the embodiments shown in Figures 4 and 5, the fitting may be selected according to its handing so that the unused hook will consistently be on either the outside of the upright (as illustrated), or will always be on the inside of the upright. This may be advantageous, in that securing the fittings so that the unused hook is disposed on the outside ensures that the unused hook will not impede a user's access up and down the ladder. It will be appreciated that when the fittings are all of the same handing, for a given ladder, it will be necessary to position one of the fittings with the unused hook disposed on the outside of one upright, and the other fitting with the unused hook disposed on the inside of the other upright. This arrangement has not been illustrated.

Although a fitting according to the invention has been described herein for use with a ladder and scaffolding pole, it will be appreciated that such a fitting may be of use in any field where one of the structures to which it is to

be fitted does not have standard dimensions. Thus it will be appreciated that

- 12 the first end 14 of the body 11 of the fitting 10 may be of any suitable shape for engagement with the first structure. Similarly, the engagement means for engagement with the second structure need not be square hooks, and may be of any suitable form, depending on the nature of the second structure.

Finally, it will be understood that the clamp means 37 as described and illustrated may be replaced with any suitable means for securing the first end portion 14 of the body 11 to the first structure. For example, a self-locking clasp may be used instead.

Claims

- 13 CLAI1\IS

1. A fitting for securing a first structure to a second structure, said fitting comprising a body, and having a first end portion with a surface adapted to engage said first structure, and, at a position spaced from said first end portion, a first and second engagement means, wherein each of said first and second engagement means is adapted to engage said second structure, and wherein the distance between said first engagement means and said surface of said first end portion is less than the distance between said second engagement means and said surface of said first end portion.

2. A fitting as claimed in Claim 1, wherein said first structure is a

scaffolding pole.

3. A fitting as claimed in either Claim 1 or Claim 2, wherein said second structure is an upright of a ladder.

4. A fitting as claimed in any of the preceding claims, wherein said first and second engagement means each comprise a base element extending outwardly from the body of the fitting in a substantially perpendicular direction therefrom, and a lip extending from said base element towards said first end portion in a direction substantially parallel to the plane of said body.

5. A fitting as claimed in any of the preceding claims, wherein said second engagement means is formed by folding of a second end portion of the fitting.

- 14-

6. A fitting as claimed in any of the preceding claims, wherein said first engagement means is welded to said second end portion of the fitting.

7. A fitting as claimed in any of the preceding claims, wherein the body of the fitting has two opposing faces.

8. A fitting as claimed in Claim 7, wherein said first and second engagement means are located respectively on said opposite faces of the body.

9. A fitting as claimed in either of Claims 7 or 8, wherein said second end portion is provided with at least one cut so as to form at least two legs, wherein said first and second engagement means are formed by folding said legs respectively towards opposite faces of the body.

10. A fitting as claimed in Claim 9, wherein two such cuts are provided, so as to form two outer legs and one inner leg.

11. A fitting as claimed in Claim 10, wherein the first engagement means comprises said outer legs which have each been folded towards one of said faces of said body, and the second engagement means comprises said inner leg which has been folded towards the opposite face of said body.

12. A fitting as claimed in Claim 10, wherein the first engagement means comprises said inner leg which has been folded towards one of said faces of said body, and the second engagement means comprises said outer legs which have been folded towards said opposite face of said body.

- 15 -

13. A fitting as claimed in any of the preceding claims, wherein said first end portion of the fitting has an end profile containing a cut-out defining said surface for engagement with said first structure.

14. A fitting as claimed in Claim 13, wherein said cut-out is arcuate.

15. A fitting as claimed in any of the preceding claims, wherein said first end portion of the fitting is provided with a first and a second aperture therethrough.

16. A fitting as claimed in any of the preceding claims, wherein said first end portion of the fitting is provided with clamp means for securing said body to said first structure.

17. A fitting as claimed in Claim 16, wherein said clamp means comprises an externally threaded rod, an internally threaded nut threadably engaged with said externally threaded rod, and an arm adapted to engage said first structure.

18. A fitting as claimed in Claim 17, wherein said externally threaded rod and said arm are each pivotably connected to said first end portion of the fitting.

19. A fitting as claimed in Claim 15, wherein said first end portion of the fitting is provided with clamp means for securing said body to said first structure, said clamp means comprising an externally threaded rod, an

- 16 internally threaded nut threadably engaged with said externally threaded rod, and an arm adapted to engage said first structure, and wherein said rod is fitted via a pin at said first aperture, and said arm is fitted via a pin at second aperture, such that said rod and arm may be pivoted about said respective apertures.

20. A fitting as claimed in any of Claims 17 to 19, wherein said arm has an aperture therethrough, such that, in use, when said arm is engaged against said first structure, said externally threaded rod is passed through said arm aperture and said internally threaded nut is tightened to secure the fitting to said first structure.

21. A fitting as claimed in any of the preceding claims, wherein said fitting is formed from metal.

22. A fitting as claimed in any of the preceding claims, wherein said fitting is formed from mild steel.

23. A fitting as claimed in any of the preceding claims, wherein the body comprises a substantially flat plate.

24. A fitting for securing a first structure to a second structure, said fitting comprising a body, and having a first end portion with a surface adapted to engage said first structure, and, at a position spaced from said first end portion, a first and second engagement means, wherein each of said first and second engagement means is adapted to engage said second structure, and wherein the distance between said first engagement means and said surface of

- 17 said first end portion is less than the distance between said second engagement means and said surface of said first end portion, and said first end portion of the fitting is provided with clamp means for securing said body to said first structure.

25. A fitting substantially as hereinbefore described, with reference to, and as shown in the accompanying drawings.

26. A method for manufacturing a fitting includes providing a plate having a first and a second opposing face and a first end portion with a surface adapted to engage a first structure, cutting said plate so as to form at least two legs at a position spaced from said first end portion, folding at least one of said legs towards said first face, and folding at least a second of said legs towards said second face, such that each of said folded legs forms at least part of either a first or a second engagement means which is adapted to engage a second structure, wherein the distance between said first engagement means and said surface of said first end portion is less than the distance between said second engagement means and said surface of said first end portion.

27. A method for manufacturing a fitting as claimed in Claim 26, wherein one cut extends from a free edge of the plate furthest from said first end portion, towards said first end portion.

28. A method for manufacturing a fitting as claimed in Claim 27, wherein two such cuts are made, so as to form two outer legs and one inner leg.

- 18

29. A method for manufacturing a fitting as claimed in Claim 28, wherein said outer legs are folded to form said first engagement means, and said inner leg is folded to form said second engagement means.

30. A method for manufacturing a fitting as claimed in Claim 28, wherein said outer legs are folded to form said second engagement means, and said inner leg is folded to form said first engagement means.

31. A method for manufacturing a fitting as claimed in any of Claims 26 to 30, further including the step of cropping to the desired length the leg or legs which form said first engagement means.