GB2437290A

GB2437290A - Ladder with pulley

Info

Publication number: GB2437290A
Application number: GB0607968A
Authority: GB
Inventors: Paul Andrew Hartley
Original assignee: ORBIS PROPERTY PROT Ltd
Current assignee: ORBIS PROPERTY PROT Ltd
Priority date: 2006-04-21
Filing date: 2006-04-21
Publication date: 2007-10-24
Also published as: GB0607968D0

Abstract

A ladder 10 has a plurality of rungs and an upper and lower end in use. A pulley 11 is arranged at or on an upper rung 12 of the ladder. The pulley 11 may be a pulley block suspended from the rung 12. The rung may be the top rung of the ladder. A cleat may be provided toward a lower end of the ladder. The cleat allows a rope supporting a load via the pulley to be held in place, suspending the load in a raised position. The ladder is especially provided for use in positioning security screens 5 ready for installation over a window of a building B.

Description

A LADDER

The present invention relates to a ladder.

A ladder is a well-known way of providing portable aboveground-level access. The most common form of ladder features two lengths of wood or metal between which are situated a plurality of cross-pieces or "rungs" that enable stepping positions for a user's feet. In use, the ladder leans against a building such that a user can climb it to bring higher places into reach, usually for maintenance purposes.

Most ladders are very basic structures that provide no additional function over the intended use as a climbing platform. A user (painter or maintenance worker) must lift equipment up the ladder, which is often awkward and dangerous.

A particular danger is present when lifting heavy loads such as a window or security screen to be fitted outside a building.

It is an object of the present invention to provide a ladder with improved function, particularly with respect to lifting loads.

In a first broad aspect of the invention there is proved a ladder including a plurality of rungs, wherein a pulley is arranged at or on an upper rung of the ladder.

Preferably the pulley is a pulley block suspended from the upper rung, preferably a top rung. In one form the pulley is a triple pulley coupled to a double pulley, in turn able to be coupled to a load.

Preferably a cleat is provided toward a lower end of the ladder (when erected next to a building) to tie off a rope threaded through the pulley in order to suspend a load. Preferably, the cleat provides a "jamming" function to capture and hold a rope.

A cleat further provides a safety function of arresting slippage in the rope if it begins to move under the load. In a preferred form the cleat is provided between the ninth or tenth rung from the top of the ladder.

The ladder of the invention enables a load to be hauled up to an aboveground level, avoiding the need for a user to manually carry that load. When performing a maintenance or installation function, use of the invention provides a working environment with improved safety.

In a second broad aspect of the invention there is provided a method for installing security screens wherein a user erects a ladder against a building in the vicinity of a window, the ladder having a pulley installed according to the first broad aspect of the invention, a load (e.g. security screen) is coupled to the pulley arrangement in a position between the ladder and the building, the load is hoisted upward toward the pulley, the load is positioned over the window and a rope of the pulley arrangement is tied off or jammed in position to suspend the load (security screen) ready for installation.

The method of the invention is a simple but effective and safe way for a worker to install a security screen to window, especially compared to existing methods that require a worker to carry the screen (sometimes up to 50kg) up a ladder in order to install it.

The present invention will be described by reference to the accompanying drawings that illustrate a preferred embodiment, wherein: -Figure 1 is a close up elevation view of an upper part of a ladder according to the invention, Figure 2 is a general elevation view of a ladder according to the invention, and Figure 3 is a pictorial view of use of a ladder according to the invention The most basic form of the present invention is retrofitting a ladder 10 with a pulley 11, suspended or otherwise attached to an upper (or a top) rung 12. As illustrated in Figure 1, pulley 11 is attached to an eye bolt 13 fastened to/through rung 12.

Pulley 11 has relatively free movement in a horizontal plane.

Pulley 11, in the illustrated embodiment has three rotatable wheels 14, usually moulded from nylon or like plastic upon which a rope (e.g. 8mm nylon rope) is threaded in the known way.

Ladder 10, in Figure 2, may be an extendable ladder to reach higher positions on a building. Also visible, toward a "lower" end (relative to when a ladder is erected against a building) is a cleat 15 which can be used to tie up or trap (jam) a rope (not shown) threaded through pulley 11. The cleat 15 further provides a safety function of arresting slippage in the rope if it begins to move under the load. In a preferred form the cleat is provided between the ninth or tenth rung from the top of the ladder.

In the illustrated embodiments of Figures 1 and 2 an additional top rung 12 has been fitted to the ladder 10. However, pulley 11 could be fitted to any of the upper rungs by a similar method (i.e. by eye bolt 13) . In further embodiments the rung may have pulley wheels integrally formed, so long as a measure of control is possible to guide the threaded rope and secure a load.

Figure 3 illustrates the intended method of use of a ladder according to the invention. Here ladder 10 is propped against a building B, with several windows W. Once stable against building B the end of a pulley rope 16 can be secured to a load, in this case a security screen S. In the preferred arrangement pulley 11 is a triple pulley, through which rope is threaded.

One length of rope 16 extends away in the direction of arrow A, while the remaining lengths form a standard block and tackle pulley arrangement to haul screen S to a workable height aboveground.

Once raised to an appropriate height the screen can be fixed in place from inside or outside the building B as needed.

The block and tackle nature of pulley 11 ensures that a worker can lift heavy loads relatively easily. A security screen S as illustrated will weigh about 50kg.

In alternative forms (especially for lighter loads) a single pulley may be used.

In all cases it is preferable to have a cleat 15 or some provision to tie rope 16 in place and enable the load to be temporarily suspended.

Preferably, the positioning of screen S is along a central axis of ladder 10 to provide balance so it is stable against building B. Feet 17 of ladder 10 should be secured against a ground surface and/or include a suitable "non-slip" surface for safest operation.

Claims

WHAT WE CLAIM IS: 1. A ladder including a plurality of rungs, wherein a

pulley is arranged at or on an upper rung of the ladder.

2. The ladder of claim 1 wherein the pulley is a pulley block suspended from the upper rung.

3. The ladder of claim 1 or 2 wherein the pulley is suspended from a top rung.

4. The ladder of any of the preceding claims wherein a cleat is provided toward a lower end of the ladder.

5. A method for installing security screens wherein a user erects a ladder against a building in the vicinity of a window, the ladder having a pulley installed according to any of the preceding claims, a load (e.g. security screen) is coupled to the pulley arrangement in a position between the ladder and the building, the load is hoisted upward toward the pulley, the load is positioned over the window and a rope of the pulley arrangement is tied off or jammed in position to suspend the load (security screen) ready for installation.

6. A ladder substantially as herein described with reference to the accompanying drawings.

7. A method for installing security screens substantially as herein described.