AU2003249787B2 - Slip inhibiting device for a ladder - Google Patents

Description

WO 2004/016898 PCTIAU2003!001033 -1- SLIP INHIBITING DEVICE FOR A LADDER The present invention relates to a slip inhibiting device suitable for use with ladders and to ladders including such a device.

One known form of ladder, when in use, is disposed in an inclined fashion against a support structure. For example the ladder may be arranged so as to be leaning against the guttering of the building enabling access to the building roof. Such an arrangement can often lead to unstable situations where the ladder may slip against the support structure thereby exposing the user to some danger of injury.

It is an object of the present invention in one aspect to provide a slip inhibiting device for a ladder which alleviates the aforementioned problem. It is a further object of the invention according to another aspect to provide a ladder which includes a slip inhibiting device.

According to one aspect of the present invention there is provided a slip inhibiting device for a ladder, the ladder including a pair of spaced apart rails and a plurality of rungs extending between the rails in spaced apart fashion in the longitudinal direction of the rails, the slip inhibiting device including an elongated body having a slip inhibiting surface, the elongated body being securable to at least one of the rails with the slip inhibiting surface being positioned so that when in use it contacts the object against which the ladder rests.

The elongated body may be in the form of an elongated strip which includes a tubular or a loop section, when viewed in cross section, of flexible material. The tubular or loop section may extend longitudinally or laterally of the strip.

Preferably the device includes two elongated bodies each being associated with a respective one of the rails.

WO 2004/016898 PCT/AU20031001033 -2- The rails of the ladder may include a side face which when the ladder is in use faces the object against which the ladder rests. Preferably the elongated bodies are operatively connected to the aforementioned side face. Furthermore the ladder includes an upper end when the ladder is in its in use orientation and preferably the elongated bodies are disposed within the region of the upper end extending in the longitudinal direction of the rails towards the other end.

The loop section may be in the form of a rectangle, square, circle, other suitable geometric or other cross-section. In one preferred form, the loop is in the form of an ellipse.

Preferably the strip includes two or more loop sections operatively interconnected or interconnected by a web section. Longitudinally extending edge flanges may be disposed at the opposite side edges of the strip.

The strip includes opposed side surfaces one of which defines a contact surface which in use contacts the object against which the ladder is positioned. Preferably this surface includes a plurality of longitudinally ribs thereon. The other surface maybe adhered or affixed in another fashion to the side face of the rail.

The strip may be formed from a plastics or an elastomeric material such as synthetic rubber such as for example EPDM although it will be appreciated that other materials may be suitable.

Preferably, the or each loop section is sealed at each end to ameliorate entry of foreign bodies to the or each loop.

According to another aspect of the present invention there is provided a ladder which includes a pair of spaced apart rails and a plurality of rungs extending between the rails in spaced apart fashion in a longitudinal direction thereof and a slip inhibiting device of the type described above secured to at least one and preferably two of the rails.

WO 2004/016898 PCTIAU2003/001033 -3- Preferred embodiments of the invention will be hereinbefore described with reference to the accompanying drawings, and in those drawings: Figure 1 is a schematic elevation of a ladder in an in use position against a building; Figure 2 is a schematic underside perspective view of a ladder and slip inhibiting device according to the present invention; Figure 3 is a schematic perspective view of a slip inhibiting device according to the present invention.

Referring to the drawings there is shown a ladder generally indicated at 30 which comprises a pair of parallel side rails 31 and 32 having an inner face 34 an upper end portion 33 and a plurality of rungs 35. The inner face of 34 of the ladder 30 when in the position shown in Figure 1 faces towards the building. As shown in Figure 1 the ladder is illustrated leaning against the gutter 52 of a building With particular reference to Figures 2 and 3 there are shown a slip inhibiting device comprising an elongated strip 12 of flexible material which is preferably an elastomer such as natural or synthetic rubber having an inner surface 14 an outer surface 15 and edges 16 and 17. The strip includes two tubular sections 18 and 19 interconnected by a web 21 with side flanges 22 and 23 at each edge thereof. On at least one surface preferably the surface which engages the support structure against which the ladder rests when in use there is provided a series of small longitudinally extending ribs 24.

As shown in Figure 2 the strips 12 are secured to the inner face 34 of each of the side rails 31 and 32. The strips may be connected by the use of an adhesive or any other suitable fastening means.

WO 2004/016898 PCT/AU20031001033 -4- The device according to the invention as described in particular with reference to the drawings exhibits significant advantages over prior art devices. For example the tubular structure of the device in its preferred form permits the rubber walls to collapse onto the contact surface of the support structure with little weight required and an effective grip obtained. The weight of the ladder is sufficient to create a grip however the addition of the weight of the user when on the ladder increases the effectiveness of the grip at the contact points of the surfaces. Importantly, the higher a user generally travels on the ladder, the more reaction force is provided to the contact points. Thus, more stability is provided, when a user is further from the ground. Furthermore the structure creates a flexible air cushion which automatically adjusts between each point of contact and the ladder. The air space between the tube walls maximises the cushion and impact absorbing effect. The rubber walls of these tubular structure limit sideways movement in two ways.

Firstly the application of pressure results in the collapse of the tubes at the point of contact.

However the tube sections above and below the contact point retain their shape and this enables the tubes to create a locking effect at the contact point. Secondly on compression the tube structures meet internally creating a double binding affect with one side attached to the ladder and the other side attached to the point of contact through pressure and friction. The use of a resilient rubber compound in a tubular structure means that the surface of the ladder grip is not abraded, damaged or permanently compressed due to pressure with the contact surface. The resilient rubber compound will return to its original tubular structure following the release of pressure from the contact point. This ensures a long and effective working life of the device.

Finally, it is to be understood that various alterations, modifications and/or additions may be incorporated into the various constructions and arrangements of parts without departing from the spirit or anmbit of the invention.

Claims (18)

1. A slip inhibiting device for a ladder, the ladder including a pair of spaced apart rails and a plurality of rungs extending between the rails in spaced apart fashion in the longitudinal direction of the rails, the slip inhibiting device including an elongated body having a slip inhibiting surface, the elongated body in the form of an elongated strip which includes a tubular or a loop section, when viewed in cross section, of flexible material; the elongated body further being securable to at least one of the rails with the slip inhibiting surface being positioned so that when in use it contacts an object against which the ladder rests, the tubular or loop section when installed having a rear face which is mounted on a contact face of the rail which faces the object against which the ladder rests when the ladder is in use, so that the tubular or loop section is disposed between the object and the contact face of the ladder rail.

2. A slip inhibiting device according to claim 1 wherein said tubular or loop section extends longitudinally of the strip.

3. A slip inhibiting device according to claim 1 wherein said tubular or loop section extends laterally of the strip.

4. A slip inhibiting device in accordance with any preceding claim, the device including two elongated bodies, each one being associated with a respective one of the rails.

5. A slip inhibiting device in accordance with any previous claim, the ladder including an upper end when the ladder is in its in use orientation wherein the elongated bodies are disposed within the region of the upper end extending in the longitudinal direction of the rails towards the upper end.

6. A slip inhibiting device in accordance with any previous claim wherein the tubular or loop sections are closed loops. SHE PCT/AU2003/00103: Received 30 April 200- P:\WPDOCS\LMB\Lcstcr MilleSpccicalions \78262003 ptLdoc-30 April, 2004 -6-

7. A slip inhibiting device in accordance with any previous claim wherein the loop section is in the form of an ellipse.

8. A slip inhibiting device in accordance with any previous claim wherein the strip includes two or more loop sections interconnected by respective web sections.

9. A slip inhibiting device in accordance with any previous claim wherein longitudinally extending edge flanges are disposed at the opposite side edges of the strip.

A slip inhibiting device in accordance with any previous claim wherein the strip includes opposed side surfaces one of which defines a contact surface which in use contacts the object against which the ladder is positioned.

11. A slip inhibiting device in accordance with claim 10 wherein the contact surface includes a plurality of longitudinally extending ribs thereon.

12. A slip inhibiting device in accordance with claim 11 wherein the other surface is adhered or affixed in another fashion to the side face of the rail.

13. A slip inhibiting device in accordance with any previous claim wherein the strip may be formed from an elastomeric material such as synthetic rubber such as for example EPDM.

14. A slip inhibiting device in accordance with any previous claim wherein the or each loop section is sealed at each end of the elongated body to ameliorate entry of foreign bodies to the or each loop section.

A ladder which includes a pair of spaced apart rails and a plurality of rungs extending between the rails in spaced apart fashion in a longitudinal direction thereof and a slip inhibiting device in accordance with any previous claim secured to one of the rails. iV EED SHEET Ir A PCT/AU2003/001032 Received 30 April 2004 FWPDOCALMBVLcrstr WaXr\SpwciftcatimsW82pctdo.30 Aptil, 2004 -7-

16. A ladder which includes a pair of spaced apart rails and a plurality of rungs extending between the rails in spaced apart fashion in a longitudinal direction thereof and a slip inhibiting device in accordance with any previous claim secured to two of the rails.

17. A slip inhibiting device substantially as hereinbefore described with reference to the drawings.

18. A ladder substantially as hereinbefore described with reference to the drawings. DATED this 30 th day of April, 2004 MARK OLESEN By his Patent Attorneys DAVIES COLLISON CAVE IriiEi-~1DEGh 8HEFi I;P&~i~a~d