GB2425324A

GB2425324A - Ladder with treads maintained in horizontal position

Info

Publication number: GB2425324A
Application number: GB0508132A
Authority: GB
Inventors: Robert David Black; John Alexander Black
Original assignee: Individual
Current assignee: Individual
Priority date: 2005-04-22
Filing date: 2005-04-22
Publication date: 2006-10-25
Also published as: GB0508132D0

Abstract

A ladder 11 has treads 14 pivotally connected to two side members 12, 13. An angling member 17 is provided parallel to the side members and is also connected to each tread by a hinge (19). When placed in a working position, the angling member contacts the ground, and acting in combination with the side members, causes the treads to assume a horizontal position. The treads lie substantially parallel to the side members for storage. A second angling member may also be provided. Preferably means are provided for attaching the ladder to an external support to prevent displacement of the ladder.

Description

1 2425324

LADDER

TECHNICAL FIELD

This invention relates to a ladder. In particular it is particularly, but not exclusively, concerned with a step ladder for use in a building under construction or modification.

In such a building movement between floors is often required before stairs have been installed though apertures in floors for stairs exist.

BACKGROUND ART

To an extent a temporary need to move between floors can be met by a conventional ladder. However from a safety standpoint a conventional ladder does not necessarily suit a user who is carrying a load which is heavy or bulky or both. A conventional ladder is frequently provided with rungs of circular, or substantially circular, cross section. Such a cross sectional shape ensures that the support presented to the foot of a user does not alter regardless of the inclination of the ladder. However a relatively narrow rung provide a relatively limited contact area between the rung and the foot of a user. This can be inconvenient whether to somebody going up or down the ladder or to somebody working which require them to stand on the ladder.

Ladders can also be equipped with treads rather than rungs. A tread of flat section provides a larger working surface to a foot of a user enabling the weight of the user to be distributed over a larger area than that afforded by a rung. However the tread needs to be disposed substantially horizontally so the angle at which the ladder can be used is limited to a narrow range.

DISCLOSURE OF INVENTION

According to the present invention there is provided a ladder with: longitudinal side members each having a longitudinal axis and each having a treads located between the side members, each tread having a working surface and extending between the side members, pivot means linking each tread to each side member to provide for the tread to pivot about a tread axis perpendicular to the longitudinal axis of each side member; and an angling member having a longitudinal working axis and a working end, the working axis being parallel to the longitudinal axis of each side member; and pivot means whereby the angling member is pivotably attached to each tread so that- in a working configuration the working ends of the side members and the working end of the angling member when placed on a plane surface, act in combination, to cause the working surface of each tread to lie parallel to the plane surface; and in a storage configuration the working surface of each tread is disposed by means of the angling member to lie substantially parallel to the longitudinal axis of each side member.

According to a first preferred version of the present invention there is provided a further angling member having a further longitudinal working axis and a working end, the further longitudinal axis being parallel to the longitudinal working axis of the angling member and to the longitudinal axis of each side member; the further angling member being pivotably attached to each tread so that: in a working configuration the working ends of the side members, the angling member and the further angling member when placed on a plane surface, act in combination, to cause the working surface of each tread to lie parallel to the plane surface; and in a storage configuration the working surface of each tread is disposed by means of the angling member and further angling member to lie substantially parallel to the longitudinal axis of each side member.

According to a second aspect of the present invention or of the first preferred version thereof the ladder is equipped with means for attaching the ladder to an external support to inhibit unintended displacement of the ladder or a component thereof.

In the present context a tread is taken to be a member with a working surface for standing on by a user the member being of indefinite width (from side to side) and whose depth (from front to back) is greater than its thickness (from top to bottom).

This contrasts with a rung whose depth is similar to its thickness.

BRIEF DESCRIPTION OF DRAWINGS

An exemplary embodiment of the present invention will now be described with reference to the accompanying drawings of a prototype of a ladder of which: Figure 1 is a front view of the ladder in a fully extended working configurahon; Figure 2 is a close-up of part of the ladder of Figure 1 with its components in an intermediate position between a working and a storage configuration; and Figure 3 is a close-up of the ladder of Figure 1 with components in a storage configuration.

MODE FOR CARRYING OUT THE INVENTION

The figures variously show a ladder 11 with side members 12, 13 having, respectively, longitudinal axis 12L, 13L and working ends 12E, 13E Treads, typically tread 14, are mounted between the side members 12, 13. Tread 14 will now be described in more detail but the remaining treads are similar in form and function. Tread 14 has ends 15, 16 with pivots enabling the tread 14 to pivot about tread axis 14A with respect to side members 12, 13. The tread axis 14A is perpendicular to longitudinal axis 12L, 13L. The tread 14 has a working surface 14S on its upper side.

An angling member 17 has a longitudinal working axis 17L and a working end 17E.

The working axis 17L lies parallel to the longitudinal axis 12L, 13L of the appropriate side member 12, 13.

The angling member 17 is pivotably attached to tread 14 (see Figure 3) by a hinge 19.

By manipulating the angling member 17 the components of the ladder 11 can be positioned in a working configuration or a storage configuration.

Figure 1 shows the ladder 11 with its components in their working configuration.

Working ends 12E, 13E of the side members 12, 13 and the working end 17E of angling member 17 are shown positioned at the apices of a triangle on floor F which is horizontal. As a result the working surface 14S of tread 14 is automatically located parallel to floor F (that is to say horizontally). In a similar fashion the remaining treads are also automatically positioned parallel to the floor F and to one another. In this way, regardless of the inclination of the side members 12, 13, it is possible for the ladder to be configured with the surface of each tread depending entirely on the relative alignment of working ends 12E, 13E, 17E.

Figure 2 shows part of ladder 11 when the angling member 17 has started to be displaced upwardly causing tread 14 to start to pivot about its axis 14A. The remaining treads pivot in a corresponding way.

Figure 3 shows the completion of the tread pivoting action at which point working surface 14S of tread 14 lies parallel to the longitudinal axis 12A, 13A of, respectively, side members 12, 13 (and also to longitudinal axis 17A of angling member 17). In this storage configuration the ladder 11 can be readily stored or transported. In this configuration clip or other means can be provided to demountably secure the angling member 17 to one or more of the treads to keep the components aligned in the storage configuration. In the storage configuration the ladder can be used as a horizontal walk way since the gaps between the treads are of the same order as the depth of the treads themselves. In a conventional ladder with rungs the spaces between the rungs are much greater than the width of the rungs themselves which would make the use of a ladder when lying horizontally very dangerous since the chance of a foot slipping into a gap between rungs would be very high.

In further embodiments means can be provided to positively secure the ladder in a given location to a suitable fixture. The ladder in the prototype described is of wood.

Apart from wood, plastics or metals could be used of combinations of some or all of these. A ladder according to the present invention is readily coated to a greater or lesser extent with distinctive materials, instructions, signs of ownership or origin, testing procedures or whatever.

INDUSTmAL APPLICABILITY

The ladder of the present invention provides a readily used means for moving vertically between levels by means of a simple trade ladder providing for alignment of treads automatically by standing the ladder on a surface with which the treads will then be aligned. Such a ladder is applicable to a wide range of industries including constructional, building and equipment installation amongst many others.

Claims

A ladder with: longitudinal side members each having a longitudinal axis and each having a working end; treads located between the side members; each tread having a working surface and extending between the side members, pivot means linking each tread to each side member to provide for the tread to pivot about a tread axis perpendicular to the longitudinal axis of each side member; and an angling member having a longitudinal working axis and a working end, the working axis being parallel to the longitudinal axis of each side member; pivot means whereby the angling member is pivotably attached to each tread so that- in a working configuration the working ends of the side members and the working end of the angling member when placed on a plane surface, act in combination, to cause the working surface of each tread to lie parallel to the plane surface; and in a storage configuration the working surface of each tread is disposed by means of the angling member to lie substantially parallel to the longitudinal axis of each side member.
2 A ladder as claimed in Claim 1 having a further angling member having a further longitudinal working axis and a working end, the further longitudinal axis being parallel to the longitudinal working axis of the angling member and to the longitudinal axis of each side member; the further angling member being pivotably attached to each tread so that in a working configuration the working ends of the side members, the angling member and the further angling member when placed on a plane surface, act in combination, to cause the working surface of each tread to lie parallel to the plane surface; and in a storage configuration the working surface of each tread is disposed by means of the angling member and further angling member to lie substantially parallel to the longitudinal axis of each side member.
3 A ladder as hereinbefore described with reference to the accompanying drawings.
4 A ladder as claimed in any preceding claim equipped with means for attaching the ladder to an external support to inhibit unintended displacement of the ladder or a component thereof.