AU2008202187A1

AU2008202187A1 - Ladder stabiliser

Info

Publication number: AU2008202187A1
Application number: AU2008202187A
Authority: AU
Inventors: Barrie Weatherall
Original assignee: Rojak Design Ltd
Current assignee: Rojak Design Ltd
Priority date: 2007-05-17
Filing date: 2008-05-16
Publication date: 2008-12-04
Also published as: GB2454280A; GB0808844D0; GB0709499D0

Description

AUSTRALIA

Patents Act COMPLETE SPECIFICATION

(ORIGINAL)

Class Int. Class Application Number: Lodged: Complete Specification Lodged: Accepted: Published: Priority Related Art: Name of Applicant: Rojak Design Ltd Actual Inventor(s): Barrie Weatherall Address for Service and Correspondence: PHILLIPS ORMONDE FITZPATRICK Patent and Trade Mark Attorneys 367 Collins Street Melbourne 3000 AUSTRALIA Invention Title: LADDER STABILISER Our Ref: 829305 POF Code: 468180/487484 The following statement is a full description of this invention, including the best method of performing it known to applicant(s): -1- PARJBA669 AU 00 LADDER STABILISER

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This application claims priority from British Application No.0709499.8 filed 17 May 2007, the contents of which are to be taken as incorporated herein by this reference.

O This invention relates to a ladder stabiliser, particularly to a releasably securable ladder stabiliser, and to a method of stabilising a ladder.

Ladders are used in a wide range of applications both domestically and commercially r- 00 and in many different environments as regards the ground upon which the base of the ladder is placed and the wall against which the top of the ladder rests. The ground may for example be uneven or inclined, slippery or loose for example due to ice, gravel, grass, moss, building 00 site debris and the like, all of which may present a hazard unless due care is taken by the user. Various stabilising devices have been developed to reduce the risk of such hazards arising by providing improved stability for the feet of the ladder and to enable ladders to be Semployed safely more widely.

The wall against which the ladder rests may also present hazards. For example, the wall may be uneven, not precisely vertical or there may be obstructions such as windows and drain pipes, gutters and the like. In addition, as a practical matter, the user may lean laterally of the ladder and thereby impart greater force to one side or the other of the ladder and cause the top of the ladder to move. This is particularly dangerous as once the ladder becomes unstable together with the weight of the user exacerbating the instability, serious accidents may occur. Where a ladder is used towards the end of a wall, lateral slippage may cause the ladder to move beyond the end of the wall and lose support altogether with potentially major consequences.

Ladder stiles often have rubber stops to provide improved grip between the ladder and the wall against which it is leant but this may provide only limited improvement in stability. Furthermore, ladders may also be used to gain access to roof areas or to scaffolding where the stiles of the ladder rather than the top of the ladder is in contact with the structure thereby rendering the rubber stops redundant in such circumstances.

Ladders must also comply with legislation regarding working at height in certain countries for example Work At Height Regulations (WAHR) in the UK based in a European Directive and employers may have a duty of care to employees to ensure equipment used in the course of employment is safe and meets all appropriate regulations.

Various attempts have been made to provide improved ladder stability and a stabilising device, generally known as a "stand-off", is known. A stand-off attaches to a ladder and presents a surface to the wall such that the ladder itself does not contact the wall.

A stand-off typically comprises a framework and retention brackets or hooks for attachment PARJBA669 AU 00oO to the rungs of the ladder and means for securing the stand-off to the ladder. Once assembled, the framework projects in front of the ladder and presents a surface for abutment (-i to the wall. Stand-offs further comprising wheels attached to the frame such that the wheels contact the wall are also known and may include a shaped notch in the frame to allow the stand-off to be used in the corners of walls. However, where such standoffs are used against corners of walls, typically the shaped notch rests against the corner of the wall but the wheels do not contact the walls.

The use of wheels made of rubber and which are deformable into a shape so as 00oO to present a flat rather than curved surface of the wheel are also known.

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C) A need still exists for further improvement in ladder safety and particularly in

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00oO stabilising the top end of the ladder during use. We have now found that a ladder stabiliser having two or more rotatable balls for contact with the wall against which the ladder is to be used provides significant improvements in ladder safety, ease of use and the range of circumstances in which the ladder may be safely used.

According to a first aspect of the invention, there is provided a ladder stabiliser for use with a ladder positioned against a wall, the ladder stabiliser comprising a body, means for releasably securing the body to the ladder and two or more rotatable balls mounted on the body, the arrangement being such that, in use, the body projects away from the ladder and the two or more balls are mounted at or near the projecting end of the body whereby the balls present a contact surface for abutting the wall.

Preferably, the stabiliser extends laterally to the plane of the ladder such that the balls are located forward of the plane of the ladder thereby affording the user a working position away from the wall against which the ladder and stabiliser is mounted.

Suitably, the two or more balls are not wheels as wheels mounted in a vertical plane about a horizontal axis have the disadvantage that they present a flat horizontal contact surface to the wall. The balls employed in the present invention, although horizontally mounted advantageously provide a curved horizontal surface so providing a secure mounting surface against rough or uneven walls.

The rotatable balls provide a curved contact surface rather than a planar surface as is the case with known stabilisers or stand-offs. Advantageously, this allows the stabiliser to be used on rough or uneven walls as well as smooth walls and also permits each side of the ladder to abut surfaces which are in different planes such as where there is a change in direction of the wall and the ladder is to be employed with the rails straddling the change in direction, for example a corner of adjoining walls. In this case, the tangent at the point of contact for each wall is different yet the ladder retains stability due to the use of rotatable balls to provide an abutment surface.

PARJBA669 AU OO The balls are suitably mounted so they are rotatable about an axis which is preferably

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0 horizontal in use whereby the balls may roll up and down a vertical surface but not to any (-i material degree laterally across the surface. Preferably, each ball is mounted on the body by means of an axle which extends from the body in a direction generally parallel to the plane of the ladder. Desirably the at least two rotatable balls are mounted facing each other so as to

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present generally facing abutment surfaces so allowing use on corners of walls.

In a preferred embodiment, the stabiliser comprises four rotatable balls, mounted in pairs. Preferably two supports extend from the body, in use, in a direction away from the

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ladder and spaced apart, desirably at or near opposite ends of the body, a pair of axles are S) mounted on each support and a rotatable ball on each axle. The supports are desirably OO spaced apart by at least the width of the ladder with which the stabiliser is being used.

SThe rotatable balls may be made of any suitable material to provide adequate grip on abutment with a wall. Preferred materials include rubber, plastics materials and the like.

The body projects laterally of the ladder in use and comprises the releasable securing means by which the body is attached to the ladder at or one end of the body and the rotatable balls at the distal end of the body from the ladder. The body may be solid but preferably comprises a frame. The frame suitably comprises an upper shaped strut and a lower shaped strut connected to each other, desirably with each shaped strut having two parallel sides and a third middle side joining the two sides being perpendicular to the two parallel sides. The struts may be joined to each other at or near the tips of the so the plane of the two generally shaped struts are inclined relative to each other.

Alternatively and preferably, the two shaped struts are joined together by a further pair of spacing struts arranged generally perpendicular to the shaped struts and connecting the C" shaped struts together at or near both their ends. In this embodiment, the shaped struts are generally in parallel planes. As desired, additional struts may be employed to join the two shaped struts to provide additional structural integrity and these struts may be located at any point on the shaped struts and are generally parallel to the spacing struts and perpendicular to the shaped struts.

The shaped struts are suitably dimensioned so as to fit around a ladder with the side parts of the extending past the outside of the two ladder rails.

The releasable securing means are suitably located at or near the middle side on either and preferably both shaped struts and the rotatable balls are located at or near the end of the of the strut, desirably on the upper shaped strut where the two shaped struts are spaced apart.

At least one and desirably both of the shaped struts has a further bracing strut which joins the two ends of the shaped strut so closing the and forming a box. This PARJBA669 AU 00 arrangement adds strength to the body and is particularly desirable for heavy duty applications.

The body is preferably made of a rigid, durable light-weight material, for example aluminium.

The present invention is particularly advantageous for use with ladders on corners of adjoining walls and in avoiding obstructions in the wall for example drain pipes. In an especially preferred embodiment, the body comprises two connected shaped struts and at least one bracing strut wherein the bracing strut is shaped. The of the bracing strut 00 faces into the shaped strut and is suitably dimensioned and adapted to, in use, (-i 0) accommodate but not be in contact with a projecting corner edge of a wall or a drainpipe or 00 other projection away from the plane of the wall. The arrangement of the at least two balls is such that when the ladder stabiliser is used on a corner of two walls, the balls are in contact with the two walls but the shaped bracing strut does not contact the walls or the corners unlike known ladder stabilisers.

Furthermore, the shaped strut allows the ladder to be rested against narrow structures, for example, lamp posts, telegraph poles, whereby the shaped brace is in contact and rests against the narrow structure. Preferably the ladder stabiliser comprises fixing means which may be placed around the narrow structure to secure the ladder stabiliser against the narrow structure.

Suitably, the means for releasably securing the body to the ladder are easily operated manually. Whilst a mechanism requiring the use of tools may be employed, desirably the said means are manually operable without the use of tools for the convenience of the user.

The securing means preferably engage with a rung and desirably two rungs of the ladder to provide improved stability and retain the ladder stabiliser in fixed relation to the ladder during use. The securing means may comprise a hooked bracket extending upwardly from the body and adapted to fit over a ladder rung. The securing means may further comprise means for bracing the securing means against the rungs and/or stiles of the ladder.

In a preferred embodiment, the securing means preferably comprises a pivotally mounted bracket which is manually moveable to engage the bracket with a rung and which may be disengaged by moved the ladder stabiliser upwards along the ladder. The bracket suitably presents an upward facing camming surface on the top of the bracket whereby as the stabiliser is moved upwardly, the camming surface contacts the next rung and pivots out of the line of the rung so the stabiliser may pass beyond to the next rung where the process is repeated.

In an especially preferred embodiment, the securing means comprises two pivotally mounted brackets, spaced apart so as to engage two rungs, preferably successive rungs of the ladder.

PARJBA669 AU 00 Preferably the securing means is secured in place using fixing means, desirably an expandable connector, for example spring clips which may be passed around adjacent rungs on the ladder. However, the distance between adjacent rungs may be different from ladder to ladder and the fixing means suitably have a degree of "play" which disadvantageously may Sallow the stabiliser to move along the rung. The fixing means may also be employed to secure the ladder stabiliser against a narrow structure as desired.

In a preferred embodiment, the fixing means comprises a ratchet belt and means for engaging the belt, for example a retaining eye. The belt is suitably connected to the body of 00 the stabiliser and in use is passed around one or more rungs and engaged at an appropriate

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S tension or, where the ladder stabiliser comprises a V shaped bracing strut and is employed 00 against a narrow structure, the belt may be passed around the narrow structure and fastened so securing the ladder stabiliser to the narrow structure. The belt avoids the disadvantage of retaining springs as it does not require any "play" and suitably remains in tension during use thereby firmly holding the ladder stabiliser in place.

The ladder stabiliser may comprise guide means to guide the location of the stabiliser on the ladder. The guide means suitably engage with the rails of the ladder on placing the stabiliser at the end of the ladder and allow the stabiliser to be slid along the rails to the appropriate location at which point the stabiliser may be located in place using the fixing means.

In a preferred embodiment, the invention provides a ladder stabiliser for use with a ladder positioned against a wall, the ladder stabiliser comprising a body which comprises a frame having an upper shaped strut and a lower shaped strut connected to each other, means for releasably securing the body to the ladder which comprises a pivotally mounted bracket which in use is manually moveable to engage the bracket with a rung on the ladder and disengagable by moving the ladder stabiliser along the ladder, fixing means for securing the bracket on the rung of the ladder in use and two or more rotatable balls rotatably mounted on the body about an axis which is horizontal in use whereby the balls are rotatable vertically on the wall the arrangement being such that, in use, the body projects away from the ladder and the two or more balls present a contact surface for abutting the wall. In a further preferred embodiment, the frame further comprises a shaped bracing strut.

The invention also provides in a second aspect a stabilised ladder kit comprising a ladder and a ladder stabiliser according to the present invention.

The invention is illustrated in a non-limiting manner by reference to the accompanying drawing s in which: Figure 1 shows a perspective view of a ladder stabiliser according to the invention; PARJBA669 AU 00 Figure 2 shows a side view of a ladder stabiliser according to the invention attached 0 to the rungs of a ladder; Figure 3 shows a side view of a ladder stabiliser according to the invention in situ on a ladder and resting against a wall.

Figure 4 shows a plan view of a part of a ladder stabiliser according to the invention in situ on a ladder and resting against two walls which meet at a corner edge.

The ladder shown in Figure 1 has 4 balls rotatably mounted in pairs on 2 axles The axles are connected to a frame which comprises a first C shaped strut (10) and a 00 second C shaped strut (11) joined at the ends of the of each strut. A bracing strut (3) S having a V shape links the two ends of the shaped struts together to provide additional 00 structural rigidity and strength and is able to accommodate a projection on a wall or a corner of a wall. Brackets are provided to engage with the rungs of a ladder. Fixing means comprising a ratchet belt (not shown) and a retaining eye is provided which additionally secures the ladder stabiliser to the ladder.

Figure 2 shows a ladder stabiliser affixed to a rung on a ladder having a ratchet belt (not engaged) as fixing means. The ladder stabiliser also has part on the bracket which abuts a lower rung and provides additional stability.

In Figure 3, the ladder stabiliser of the invention is shown releasably secured to a ladder The brackets are engaged with an upper rung and the ratchet belt is passed under a lower rung and secured on the retaining eye and tensioned. The part of the bracket abuts a lower rung and braces the ladder stabiliser against the ladder The brackets the fixing means and and part act in concert to provides stability by placing the ladder stabiliser in fixed relation to the ladder The ladder is then placed in position against a wall and the balls contact the wall and hold the ladder away from the wall.

Figure 4 shows a part of the ladder stabiliser of the invention in use supporting a ladder against two walls meeting at a corner edge. The balls are provided in two pairs with each pair being rotatably mounted on axles with the two balls engaging the wall being mounted such that they face each other. The inner balls rest against the walls and engage at non-parallel tangents. The projecting corner edge where the walls meet is accommodated in, and desirably not in contact with the shaped bracing strut

Claims

1. A ladder stabiliser for use with a ladder positioned against a wall, the ladder stabiliser comprising a body, means for releasably securing the body to the ladder and two or more Srotatable balls mounted on the body, the arrangement being such that, in use, the body projects away from the ladder and the two or more balls are mounted at or near the projecting end of the body whereby the balls present a contact surface for abutting the wall. r- 00

2. A ladder stabiliser according to claim 1 in which the rotatable balls provide a curved (N contact surface for the wall. 00

3. A ladder stabiliser according to claim 1 or claim 2 wherein the balls are mounted so as to be rotatable about an axis which is horizontal in use whereby the balls may roll up and down a vertical surface.

4. A ladder stabiliser according to any one of the preceding claims wherein the at least two rotatable balls are mounted facing each other so as to present generally facing abutment surfaces.

5. A ladder stabiliser according to any one of the preceding claims which comprises four rotatable balls, mounted in pairs.

6. A ladder stabiliser according to any one of the preceding claims wherein the body comprises two supports for the rotatable balls and which supports are spaced apart by at least the width of the ladder and extend from the body in a direction, in use, away from the ladder, wherein the rotatable ball is mounted on the support.

7. A ladder stabiliser according to any one of the preceding claims wherein the rotatable balls are made of rubber of a plastics material.

8. A ladder stabiliser according to any one of the preceding claims wherein the body projects laterally of the ladder in use and comprises a frame.

9. A ladder stabiliser according to claim 8 wherein the frame comprises an upper "C" shaped strut and a lower shaped strut connected to each other. PARJBA669 AU 00

10. A ladder stabiliser according to claim 9 wherein each shaped strut has two 0 parallel sides and a third middle side joining the two sides being perpendicular to the two parallel sides.

11. A ladder stabiliser according to claim 9 or claim 10 wherein the struts are joined to each other at or near the tips of the so the plane of the two shaped struts are inclined relative to each other. 00

12. A ladder stabiliser according to claim 9 or claim 10 wherein the two shaped (N struts are in parallel planes and joined together by a pair of spacing struts arranged generally (N 00 perpendicular to the shaped struts and connecting the C" shaped struts together at or near both their ends.

13. A ladder stabiliser according to claim 12 comprising further at least one further strut to join the two shaped struts and located at any point on the shaped struts and being parallel to the spacing struts and perpendicular to the shaped struts.

14. A ladder stabiliser according to any one of claims 9 to 13 wherein at least one of the shaped struts has a bracing strut which joins the two ends of the shaped strut so closing the and the frame is in the form of a box.

A ladder stabiliser according to claim 14 wherein the bracing strut is shaped.

16. A ladder stabiliser according to any one of the preceding claims wherein the means for releasably securing the body to the ladder are manually operable without tools

17. A ladder stabiliser according to any one of the preceding claims wherein the securing means comprises a hooked bracket for engaging with a rung of the ladder in use.

18. A ladder stabiliser according to any one of the preceding claims wherein the securing means comprises a pivotally mounted bracket which is manually operable so as, in use, to engage the bracket with a rung and to disengage the bracket by moving the ladder stabiliser along the ladder.

19. A ladder stabiliser according to any one of the preceding claims wherein the securing means comprises two pivotally mounted brackets, spaced apart so as, in use, to be engagable with two rungs. PARJBA669 AU 00 A ladder stabiliser according to any one of the preceding claims in which the securing means are securable using fixing means comprising an expandable connector which remains in tension during use.

IN

21. A ladder stabiliser for use with a ladder positioned against a wall, the ladder stabiliser comprising a body which comprises a frame having an upper shaped strut and S a lower shaped strut connected to each other, means for releasably securing the body to 00 the ladder which comprises a bracket, fixing means for securing the bracket on the rung of (N the ladder and two or more balls rotatably mounted on the body about an axis which is 00 horizontal whereby in use the balls are rotatable vertically on the wall the arrangement being such that, in use, the body projects away from the ladder and the two or more balls present a contact surface for abutting the wall.

22. A ladder stabiliser according to claim 21 in which the bracket is pivotally mounted and in use is manually moveable relative to the frame to engage the bracket with a rung on the ladder and disengagable by moving the ladder stabiliser along the ladder

23. A ladder stabiliser according to any one of the preceding claims in which, in use, the stabiliser extends laterally to the plane of the ladder such that the balls are located forward of the plane of the ladder thereby affording the user a working position away from the wall.

24. A stabilised ladder kit comprising a ladder and a ladder stabiliser according to any one of the preceding claims.