GB2155528A

GB2155528A - Roof ladder

Info

Publication number: GB2155528A
Application number: GB08406135A
Authority: GB
Inventors: Livingston Brown
Original assignee: Individual
Current assignee: Individual
Priority date: 1984-03-08
Filing date: 1984-03-08
Publication date: 1985-09-25
Also published as: GB8406135D0

Abstract

A roof ladder with a cradle at one end for engagement over a roof ridge is provided with a pair of wheels adjacent the same end of the ladder but projecting in the opposite direction from the cradle. One of the wheels is mounted for rotation about a fixed axis extending parallel to the rungs of the ladder and the other is castored so as to be capable of swivelling movement about an axis at right angles to its axis of rotation and to the plane of the ladder rungs. <IMAGE>

Description

SPECIFICATION Roof ladders This invention relates to roof ladders.

Conventional roof ladders tend to be lengthy and cumbersome and to facilitate movement over a roof are commonly provided with wheels enabling the ladder- to be rolled up or down the roof and then turned over onto its other side when in position. Generally a cradle is provided at the upper end of the ladder for engagement over the ridge of the roof to retain the ladder in place once it has been correctly positioned.

The wheels provided on conventional roof ladders are mounted on fixed axles and although these facilitate movement up and down the roof they hinder adjustment along the roof since they resist sideways movement.

Since users commonly require to manipulate roof ladders while themselves standing on another ladder, considerable problems are encountered in positioning roof ladders which require to be precisely located, for example adjacent to chimney stacks or the like.

It is an object of the present invention to provide a roof ladder which may be more readily and easily manipulated compared with previously proposed roof ladders.

The invention provides a roof ladder having at one end thereof a cradle which projects from the ladder and is adapted to extend over a roof ridge to retain the ladder in position on a roof, and a pair of wheels mounted on the ladder adjacent said one end thereof but projecting in the opposite direction from said cradle, one of said wheels being mounted for rotation about a fixed axis extending parallel to the rungs of the ladder and the other being castored so as to be capable of swivelling movement about an axis at right angles to its axis of rotation and to the plane of the ladder rungs.

An embodiment of the invention will now be described, by way of example only, reference to the accompanying drawing which is a perspective view showing the upper end of a roof ladder according to the invention.

Referring to the drawing, there is shown the upper portion of a roof ladder comprising a pair of strings or stiles 5A and 5B interconnected by rungs 6 and fitted with a cradle 7 adapted to be hooked over the ridge of a roof to retain the ladder on the roof during use.

The cradle is advantageously detachably mounted on the ladder so that it may be removed and the ladder used for other purposes if required.

Wheels 8 and 9 are rotatably mounted on the respective stiles 5A and 5B. The wheel 8 is rotatable about an axle 10 extending parallel to the rungs 6 and carried in a pair of spaced support brackets 11 rigidly connected to the stile 5A. The wheel 8 is therefore fixed relative to the stile but rotatable about the axle 1 0. The wheel 9 mounted on the stile 5B is rotatable about an axle 1 2 carried by a bracket 1 3 which is still rotatably mounted on a pin 14 extending through the stile 5B and terminating in an externally threaded portion engaged by a nut 15.The wheel 9 is therefore mounted on the stile 5B in the manner of a castor which may swivel or rotate about the axis of the pin 14 which extends at right angles to the axle 1 2 and to the plane of the rungs 6.

The virtue of the provision of one fixed wheel and one castored wheel manoeuvrability of the ladder on a roof is greatly facilitated.

When the ladder is initially pushed up the roof the castored wheel 9 aligns with the fixed wheel 8 and the arrangement operates in a manner similar to conventional roof ladders.

However if it is desired to manoeuvre the ladder to one side or the other it may be tilted on to the castored wheel 9 which enables it to be readily run across the roof to the desired position. By dropping the ladder back on to the fixed wheel this acts as a brake preventing further movement and the ladder may then be pushed further up the roof if required and turned on to its other side about the fixed wheel 8 so that the cradle 7 engages over the roof ridge. If it is subsequently desired to move the ladder along the roof this may be effected by rotating it on to the wheels 8 and 9 and manoeuvring it while supported on the castored wheel 9 only. When the ladder is withdrawn down the roof the castored wheel 9 again aligns with the fixed wheel 8.

The arrangement described greatly improves manoeuvrability of a ladder over a roof while at the same time preventing loss of control such as might arise if both wheels were castored. This would make it difficult to prevent the ladder from running sideways off the roof, but the provision of one castored wheel and one fixed wheel enables any desired movement up down or across the roof to be readily effected under full control.

Various modifications may be made without departing from the invention. For example, the manner in which the fixed and castored wheels are mounted on the ladder may be altered and a different form of cradle structure may be fitted.

Whilst endeavouring in the foregoing specification to draw attention to those features of the invention believed to be of particular importance it should be understood that the Applicant claims protection in respect of any patentable feature or combination of features hereinbefore referred to whether or not particular emphasis has been placed thereon.

1. A roof ladder having at one end thereof a cradle which projects from the ladder and is adapted to extend over a roof ridge to retain

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Roof ladders This invention relates to roof ladders. Conventional roof ladders tend to be lengthy and cumbersome and to facilitate movement over a roof are commonly provided with wheels enabling the ladder- to be rolled up or down the roof and then turned over onto its other side when in position. Generally a cradle is provided at the upper end of the ladder for engagement over the ridge of the roof to retain the ladder in place once it has been correctly positioned. The wheels provided on conventional roof ladders are mounted on fixed axles and although these facilitate movement up and down the roof they hinder adjustment along the roof since they resist sideways movement. Since users commonly require to manipulate roof ladders while themselves standing on another ladder, considerable problems are encountered in positioning roof ladders which require to be precisely located, for example adjacent to chimney stacks or the like. It is an object of the present invention to provide a roof ladder which may be more readily and easily manipulated compared with previously proposed roof ladders. The invention provides a roof ladder having at one end thereof a cradle which projects from the ladder and is adapted to extend over a roof ridge to retain the ladder in position on a roof, and a pair of wheels mounted on the ladder adjacent said one end thereof but projecting in the opposite direction from said cradle, one of said wheels being mounted for rotation about a fixed axis extending parallel to the rungs of the ladder and the other being castored so as to be capable of swivelling movement about an axis at right angles to its axis of rotation and to the plane of the ladder rungs. An embodiment of the invention will now be described, by way of example only, reference to the accompanying drawing which is a perspective view showing the upper end of a roof ladder according to the invention. Referring to the drawing, there is shown the upper portion of a roof ladder comprising a pair of strings or stiles 5A and 5B interconnected by rungs 6 and fitted with a cradle 7 adapted to be hooked over the ridge of a roof to retain the ladder on the roof during use. The cradle is advantageously detachably mounted on the ladder so that it may be removed and the ladder used for other purposes if required. Wheels 8 and 9 are rotatably mounted on the respective stiles 5A and 5B. The wheel 8 is rotatable about an axle 10 extending parallel to the rungs 6 and carried in a pair of spaced support brackets 11 rigidly connected to the stile 5A. The wheel 8 is therefore fixed relative to the stile but rotatable about the axle 1 0. The wheel 9 mounted on the stile 5B is rotatable about an axle 1 2 carried by a bracket 1 3 which is still rotatably mounted on a pin 14 extending through the stile 5B and terminating in an externally threaded portion engaged by a nut 15.The wheel 9 is therefore mounted on the stile 5B in the manner of a castor which may swivel or rotate about the axis of the pin 14 which extends at right angles to the axle 1 2 and to the plane of the rungs 6. The virtue of the provision of one fixed wheel and one castored wheel manoeuvrability of the ladder on a roof is greatly facilitated. When the ladder is initially pushed up the roof the castored wheel 9 aligns with the fixed wheel 8 and the arrangement operates in a manner similar to conventional roof ladders. However if it is desired to manoeuvre the ladder to one side or the other it may be tilted on to the castored wheel 9 which enables it to be readily run across the roof to the desired position. By dropping the ladder back on to the fixed wheel this acts as a brake preventing further movement and the ladder may then be pushed further up the roof if required and turned on to its other side about the fixed wheel 8 so that the cradle 7 engages over the roof ridge. If it is subsequently desired to move the ladder along the roof this may be effected by rotating it on to the wheels 8 and 9 and manoeuvring it while supported on the castored wheel 9 only. When the ladder is withdrawn down the roof the castored wheel 9 again aligns with the fixed wheel 8. The arrangement described greatly improves manoeuvrability of a ladder over a roof while at the same time preventing loss of control such as might arise if both wheels were castored. This would make it difficult to prevent the ladder from running sideways off the roof, but the provision of one castored wheel and one fixed wheel enables any desired movement up down or across the roof to be readily effected under full control. Various modifications may be made without departing from the invention. For example, the manner in which the fixed and castored wheels are mounted on the ladder may be altered and a different form of cradle structure may be fitted. Whilst endeavouring in the foregoing specification to draw attention to those features of the invention believed to be of particular importance it should be understood that the Applicant claims protection in respect of any patentable feature or combination of features hereinbefore referred to whether or not particular emphasis has been placed thereon. CLAIMS

1. A roof ladder having at one end thereof a cradle which projects from the ladder and is adapted to extend over a roof ridge to retain the ladder in position on a roof, and a pair of wheels mounted on the ladder adjacent said one end thereof but projecting in the opposite direction from said cradle, one of said wheels being mounted for rotation about a fixed axis extending parallel to the rungs of the ladder and the other being castored so as to be capable of swivelling movement about an axis at right angles to its axis of rotation and to the plane of the ladder rungs.

2. A roof ladder according to claim 1 wherein each of said wheels is rotatably mounted in a respective support bracket, one bracket being fixed relative to its associated stile and the other being rotatable relative to its associated stile.

3. A roof ladder according to claim 1 or 2 wherein said cradle is detachably mounted on the ladder.

4. A roof ladder substantially as hereinbefore described with reference to the accompanying drawing.

5. Any novel subject matter or combination including novel subject matter herein disclosed, whether or not within the scope of or relating to the same invention as any of the preceding claims.