GB2376499A

GB2376499A - Folding ladder

Info

Publication number: GB2376499A
Application number: GB0211157A
Authority: GB
Inventors: Errol Philmore Johnson
Original assignee: Individual
Current assignee: Individual
Priority date: 2001-06-01
Filing date: 2002-05-15
Publication date: 2002-12-18
Also published as: GB0211157D0

Abstract

A folding ladder (2) comprises first and second stiles (4, 6), a plurality of rungs (8) extending between the first and the second stiles (4, 6), and a support member (10) which is positioned between the first and the second stiles (4, 6) and which extends parallel to the first and the second stiles (4, 6). The rungs (8) are in two parts with a first part (12) extending between the first stile (4) and the support member (10) and a second part (14) extending between the second stile (6) and the support member (10). The rungs (8) are pivotally mounted such that the ladder (2) is foldable between a closed position in which the first and the second stiles (4, 6) lie alongside the support member (10), and an open position in which the first and the second stiles (4, 6) are spaced apart from the support member (10) and the rungs (8) extend horizontally.

Description

A FOLDING LADDER This invention relates to a folding ladder.

Known ladders usually comprise first and second stiles, and a plurality of rungs extending between the first and the second stiles. The ladders may be single section ladders, or multi-section ladders for increasing the length of the ladders. Irrespective of whether the ladders are single section ladders or multi-section ladders, they are always of a fixed width. This fixed width is generally defined by the length of the rungs plus the combined width of the first and the second stiles. There are often occasions when the ladder is too wide for easy storage and/or transportation.

It is an aim of the present invention to reduce the above mentioned problem.

Accordingly, in one non-limiting embodiment of the present invention there is provided a folding ladder comprising first and second stiles, a plurality of rungs extending between the first and the second stiles, and a support member which is positioned between the first and the second stiles and which extends parallel to the first and the second stiles, the rungs each being in two parts with a first part extending between the first stile and the support member and a second part extending between the second stile and the support member, and the rungs being pivotally mounted such that the ladder is foldable between

a closed position in which the first and the second stiles lie alongside the support member, and an open position in which the first and the second stiles are spaced apart from the support member and the rungs extend horizontally.

The folding ladder of the present invention may be used as a simple movable ladder. In this case, the ladder can be transported in its closed position. It can also easily be stored in its closed position, for example in a cupboard in a house or office. The folding ladder of the present invention can also be used in a fixed mode in which is is secured to a vertical support surface and used as fire escape apparatus. It often happens that lives are lost in fires because persons become trapped in upper parts of buildings. The buildings can be, for example, homes, tower blocks, hotels, offices, factories or warehouses. All types of buildings can be such that stairs leading to safety are rendered impassable by a fire and/or smoke from the fire. In buildings having lifts, the lifts are often inoperable in a fire. The folding ladder of the present invention can be used on the outside of the buildings as fire escape apparatus and it has the considerable advantage that it will not occupy much space in its closed position mounted up the outside of a building. In the closed position, the folding ladder will not be very noticeable and may look like, or incorporate, a drainpipe.

In a first embodiment of the invention, the ladder is one in which the rungs are pivotally mounted by pivots

connected to the first and the second stiles. In this case, the first and the second parts of the rungs will usually fold downwardly when the ladder is folded from its open position to its closed position.

The inner ends of the first and the second parts of the rungs may be supported for rotational movement by the support member. Thus, for example, the support member may have a roller member around which the inner ends of the first and the second parts rotate. The roller member is preferably pivotally mounted so that it can rotate.

However, if desired, the roller member may be a fixed roller member.

In a second embodiment of the invention, the ladder is one in which the rungs are pivotally mounted by pivots connected to the support member. In this case, the first and the second parts of the rungs preferably fold upwardly when the ladder is folded from its open position to its closed position.

The outer ends of the first and the second parts of the rungs may be supported for pivotal movement by pivots connected to the first and the second stiles.

In all embodiments of the invention, the ladder may include stop means for stopping downward movement of the first and the second stiles when the ladder is in the open position.

The stop means may comprise a plurality of abutment members which are engaged by adjacent ends of a plurality

of the rungs when the ladder is in the open position. Usually there will be one of the abutment members for each one of the rungs of the ladder. If desired however some of the rungs may not be provided with the abutment members.

Other types of stop means may be employed if desired. Thus, for example, the stop means may comprise a plurality of apertures or recesses in each of which an end of a rung operates. When the ladder is in an open position, an upper part of the end of each rung may then abut against an upper part of its aperture or recess which then forms the stop means. The stop means may also help to maintain the ladder in a stable condition in its open position.

The ladder may be one in which the first and the second stiles form two halves of a longitudinally extending housing, the housing becoming a single closed housing which hides the rungs when the ladder is in the closed position.

Preferably, the housing is square or rectangular in cross section when the ladder is in the closed position. The housing can however be of any suitable and appropriate cross sectional shape.

The rungs are preferably of circular or rectangular cross sectional shape, but they may be of other cross sectional shapes if desired.

The rungs may have grip-enhancing surfaces for affording grip to hands and/or feet of a person ascending or descending the ladder.

The ladder may include releaseable locking means for releaseably locking the ladder in the closed position.

The releaseable locking means may be a handreleaseable catch. Any suitable and appropriate type of releaseable locking means that is easy to operate may be employed. The releaseable locking means may be provided at any suitable and appropriate position on the ladder.

The ladder may include a foot-engageable member for use in opening and closing the ladder. The foot-engaging member may be pressed on with a foot to facilitate opening of the ladder. The foot-engageable member may be kicked upwardly with a foot to facilitate closing of the ladder. Preferably, the foot-engageable member is a lever but other types of foot-engageable member may be employed.

The ladder may be made from any suitable and appropriate material. Thus, for example, the ladder may be made from aluminium. If the ladder is made from a plastics material, then the plastics material should be appropriately fire resistant.

Embodiments of the invention will now be described solely by way of example and with reference to the accompanying drawings in which: Figure 1 shows part of a first folding ladder and in an open position; Figure 2 shows part of the first folding ladder but in a closed position;

Figure 3 is a perspective view illustrating how the first folding ladder moves between its open and closed POS L L--L Figure 4 is a section on line A-A shown in Figure 1; Figure 5 is a section on line B-B shown in Figure 1 ; Figure 6 shows part of a second ladder and in an open position; Figure 7 shows the second ladder but in a closed position; Figure 8 is a section on line A-A shown in Figure 6; Figure 9 shows part of a third folding ladder of the present invention and in an open position; Figure 10 is a front view of part of a fourth folding ladder and in an open position; Figure 11 is a sectional side view of the left hand portion of the ladder part shown in Figure 10; and Figure 12 is a perspective view of a locating arrangement used in the fourth folding ladder shown in Figures 10 and 11.

Referring to Figures 1-5, there is shown a ladder 2 which is a folding ladder and which comprises a first stile 4, a second stile 6, and a plurality of rungs 8 extending between the first and the second stiles 4,6. The ladder 2 also comprises a support member 10 which is positioned centrally between the first and the second stiles 4,6 and which extends parallel to the first and the second stiles 4, 6.

The rungs 8 are each in two parts comprising a first part 12 and a second part 14. The first part 12 extends between the first stile 4 and the support member 10. The second part 14 extends between the second stile 6 and the suppor-member 10.

The rungs 8 are pivotally mounted such that the ladder 2 is foldable between a closed position in which the first and the second stiles 4,6 lie alongside the support member 10 and an open position in which the first and the second stiles 4,6 are spaced apart from the support member 10, and in which the rungs 8 extend horizontally. The open position of the ladder 2 is shown in Figure 1 and the closed position of the ladder 2 is shown in Figure 2.

The rungs 8 are pivotally mounted by pivots 16 connected to the first and the second stiles 4,6. As can be seen from Figure 2, the first and the second parts 12, 14 of the rungs 8 fold downwardly when the ladder 2 is folded from its open position shown in Figure 1 to its closed position shown in Figure 2.

The ladder 2 is such that inner ends 18 of the first and the second parts 12,14 of the rungs 8 are supported for rotational movement by the support member 10. More specifically, the support member 10 has a roller member 20 around which the inner end 18 of the first and the second parts 12,14 rotate. The roller member 20 is pivotally mounted by a pivot 22 so that it can rotate. As can be seen from Figure 5, the roller member 20 comprises two

rollers 24,26 mounted on the pivot 2. As shown in Figure 3, the inner ends 18 may be provided with a formation 28 having a curved surface for sliding around the roller member 20. Also as shown in Figure 3, the inner end 18 of the second part 14 is provided with a bridging member in the form of a bridging plate 30 for extending across any gap between adjacent inner ends 18 of the first and the second parts 12,14 when the rungs 8 are horizontal and the ladder is in the open position.

As can best be appreciated from Figures 1 and 4, the ladder includes stop means in the form of a plurality of abutment members 32 for stopping downward movement of the first and the second stiles 4,6 when the ladder 2 is in the open position. The abutment members 32 are engaged by adjacent ends 34 of the rungs 8. The abutment members 32 are formed by the top end of rectangular recesses 36 formed in the first and the second stiles 4,6.

As can best be appreciated from Figure 2, the first and the second stiles 4,6 form two halves of a longitudinally extending housing which becomes a single closed housing which hides the rungs 8 when the ladder 2 is in the closed position. The housing is of rectangular cross sectional shape when the ladder 2 is in a closed position.

The rungs 8 are of circular cross sectional shape as shown. The support member 10, as shown in Figures 1 and 3

is of single rectangular plate construction and it is smaller than the first and the second stiles 4,6.

As shown in Figures 1 and 5, the ladder 2 includes a foot-engageable member in the form of a lever 38 which extends outwardly from the support member 10. The lever 38 can be pressed down with a foot in order to facilitate opening of the ladder 2. The lever 38 can be kicked upwardly with a foot in order to facilitate closing of the ladder 2.

Referring now to Figures 6-8, there is shown a second ladder 40. Similar parts as in the ladder 2 have been given the same reference numerals for ease of comparison and understanding.

In the ladder 40, the rungs 8 are pivotally mounted by pivots 42 connected to the support member 10. As can be seen from Figure 7, the first and the second parts 12,14 of the rungs 8 fold upwardly when the ladder 40 is folded from its open position shown in Figure 6 to its closed position shown in Figure 7. This is the opposite of the downwardly folding action of the ladder 2 as shown in Figure 3.

Outer ends 44 of the first and the second parts 12,14 are supported for pivotal movement by pivots 16 connected to the first and the second stiles 4,6. However, it is the inner ends 18 of the first and the second parts 12,14 of the rungs which are engaged by abutment members 46 to stop downward movement of the first and the second stiles 4,6 when the ladder 2 is in the open position. The

abutment members 46 are N-shaped members as can be seen from Figure 8.

As can be seen from Figures 6 and 7, the support member 10 comprises two shaped parts 48,50 joined back to back. Figure 8 is a view looking into the open mouth of the part 50.

The ladders 2,40 can easily be folded and unfolded. in the folded closed position of the ladders 2,40, they are easily carried and stored in a first mode of use. When the ladder of the present invention is folded, then it can easily be transported in vehicles such for example as vans and lorries. In order to enable the ladder of the present invention to easily be carried and to be pushed into vehicles and pulled out of vehicles, the ladder may be provided with handles. The ladder may slide on the handles as it is pushed into vehicles and pulled out of vehicles, for example vans and lorries.

The ladders 2,4 can be fixed in position in the unfolded open position in a second mode of use. Thus, for example, the ladder may be unfolded and fixed to a wall, for example to provide a permanent type of access to a place, for example an attic.

In the second mode of use of the present invention, the ladders 2,40 can easily be fixed to a vertical support surface in the form of part of a wall of a building. The ladders 2,40 are thus permanently fixed outside the building for use as fire escape apparatus in the event of

fire and/or smoke preventing use of internal stairs and lifts in the building. In this mode of use of the ladders 2,40, the ladders 2,40 can be manufactured to look unobtrusive. They can also be relatively cheaply manufactured, whilst providing a much needed extra safety feature for buildings. The ladders 2,40 can be arranged to be easily operated so that even children or elderly persons can operate the ladders 2,40 in emergencies.

Where the folding ladder of the present invention is used as fire escape apparatus as described above, then it may be that persons descending the folding ladder will not be able to do so in good safety. For example the persons may be elderly persons or young children in a state of fright. In order to provide increased safety during descent of a folding ladder of the present invention, the folding ladder may be provided with a safety harness. One design of safety harness is shown by way of example in Figure 9.

Referring to Figure 9, there is shown the left hand part of a portion of a folding ladder 52. The ladder 52 has a first stile 54, a central support member 56 and rungs 58. Only the left hand half of the rungs 58 are shown in Figure 9 and it will be seen that the left hand part of the rungs 58 extend between the first stile 4 and the support member 56.

The first stile 54 is provided with a longitudinally extending groove 60 as shown. Periodically, also as shown,

the groove 60 has a hook portion 62. An arm 64 slides in the groove 60. The arm 64 forms part of a harness arrangement 66 comprising a pair of flexible arms 68 70 and a belt 72. The belt 72 can be tied around a person (not shown) and tightened by means of a buckle 74. Wrist straps 76 can be used to fasten the arms of a person to the arms 68,70 of the harness arrangement 66 as necessary.

The wrist strap 76 can be provided with buckles (not shown) or any other suitable and appropriate device for effecting the securing around the arms of the person.

During use, as a person descends the ladder 52, the arm 64 runs down the groove 62. The arm 70 has an arm 78 which runs in a similar groove extending along the outside of the second stile (not shown) of the ladder 52. The arms 64,78 can only slide along the groove 60 for the distance between the hook portion 62. This distance is formed to be a safe distance. At each hook portion 62, it is necessary for the person descending the ladder, or someone helping the person descending the ladder, to move the arms 64,70 around the hook portion 62 before further descent can be accomplished. In this way, a person in the harness arrangement 66 is prevented from falling in an uncontrolled manner down the ladder 52.

Figures 10,11 and 12 show parts of a fourth folding ladder 80. For simplicity of illustration, the central support member, for example the support member 10, has been omitted. As can be seen, the folding ladder 80 which has

all the features of the present invention, has a first stile 82 and a second stile 84. The ladder 80 is envisaged as being used for fire escape apparatus by being mounted up the outside of large buildings. Because the buildings are large, the ladder 80 needs to be in different sections and this is most easily appreciated from Figure 2 wherein it can be seen that the first stile 82 is in two sections 82A and 82B. The second stile 84 is in two sections 84A and 84B. Depending upon the height of the building provided with the folding ladder, then there may be as many more of the sections forming each stile 82,84 as are required to reach from the top of the building to the bottom of the building. Each section of the ladder 80 is able to operate independently of each other section so that the height of the building can easily be covered.

In order to make sure that the various sections 82A, 82B or 84A, 84B align with each other, an aligning device 86 can be employed. For simplicity of illustration, only one aligning device 86 has been shown between the two sections 82A and 82B. A similar aligning device can be employed at the connection between the two sections 84A and 84B.

As shown in Figures 10,11 and 12, the aligning device 86 comprises a sliding member 88 which can be slid down from a position in which it is entirely within the section 82A to a position in which is extends between the sections 82A and 82B and therefore locates and aligns the two sections 84A

and 84B together. In addition to aligning the two sections 84A and 84B together, the sliding member 88 acts to give extra stability at the join between the two sections 82A and 82B. A pin member 90 extends from both sides of the sliding member 88. The pin 90 also extends through opposite sides of the section 82A of the first stile 82, the pin 90 operating in a pair of longitudinally extending slots 92 in the outer faces of the stile section 82A.

Because the stile 82 is U-shaped in cross section, slots 92 also have to be provided on the inner faces of a channel 94 forming the inside part of the first stile 82. As can best be seen from Figure 12, the sliding member 88 slides in this channel 94.

Also shown in Figures 10,11 and 12 are rungs 96.

These rungs 96 are shown somewhat schematically as pivoting about pivots 98,100 about the first and second stiles 82, 84 respectively.

It is to be appreciated that the embodiments of the invention described above with reference to the accompanying drawings have been given by way of example only and that modifications may be effected. Thus, for example, the ladder of the present invention can be made in a wide variety of designs. Abutment members other than the illustrated abutment members 32 and 46 may be employed. When the first and the second stiles 4,6 are closed, they may form a housing which is square in cross section rather than rectangular. In Figure 9, the portion of the arms 68,

70 between the wrist straps 76 and the arms 64,68 can be made of an increased size to provide a comfortable hand grip for persons gripping the arms 68,70 as they descend the ladder 52. The arms 68,70 can be made of any suitable and appropriate material including leather and plastics materials. The arms 64,78 will usually be made of a metal although they may be made of other materials if desired.

The rungs in the ladder of the invention may be of rectangular cross section instead of circular cross section if desired. The rungs may also be provided with gripenhancing surfaces for affording grip to hands and/or feet of a person ascending or descending the ladder. The ladder of the invention may be provided with releaseable locking means such for example as a hand-releaseable catch (not shown) for releaseably locking the ladder in the closed position. The ladder may be provided with trunking. The trunking can be permanently fixed to the ladder or removable from the ladder. The support member may have stabiliser means adjacent the top and/or bottom rungs of the ladder. Any suitable and appropriate type of stabiliser may be employed.

Where the ladder of the invention is provided with a safety harness, then the safety harness can be of any suitable and appropriate construction including a belt, a jacket, or a strap arrangement such as is used with a parachute.

Claims

CLAIMS 1. A folding ladder comprising first and second stiles, a plurality of rungs extending between the first and the second stiles, and a support member which is positioned between the first and the second stiles and which extends parallel to the first and the second stiles, the rungs each being in two parts with a first part extending between the first stile and the support member and a second part extending between the second stile and the support member, and the rungs being pivotally mounted such that the ladder is foldable between a closed position in which the first and the second stiles lie alongside the support member, and an open position in which the first and the second stiles are spaced apart from the support member and the rungs extend horizontally.
2. A folding ladder according to claim 1 in which the rungs are pivotally mounted by pivots connected to the first and the second stiles.
3. A folding ladder according to claim 2 in which the first and the second parts of the rungs fold downwardly when the ladder is folded from its open position to its closed position.

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4. A folding ladder according to claim 2 or claim 3 in which inner ends of the first and the second parts of the rungs are supported for rotational movement by the support member.
S. A folding ladder according to claim 4 in which the support member has a roller member around which the inner ends of the first and the second parts rotate.
6. A folding ladder according to claim 5 in which the roller member is pivotally mounted so that it can rotate.
7. A folding ladder according to claim 1 in which the rungs are pivotally mounted by pivots connected to the support member.
8. A folding ladder according to claim 7 in which the first and the second parts of the rungs fold upwardly when the ladder is folded from its open position to its closed position.
9. A folding ladder according to claim 7 or claim 8 in which outer ends of the first and the second parts of the rungs are supported for pivotal movement by pivots connected to the first and the second stiles.

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10. A folding ladder according to any one of the preceding claims and including stop means for stopping downward movement of the first and the second stiles when the ladder is in the open position.
11. A folding ladder according to claim 10 in which the stop means comprises a plurality of abutment members which are engaged by adjacent ends of a plurality of the rungs when the ladder is in the open position.
12. A folding ladder according to claim 11 in which there is one of the abutment members for each one of the rungs of the ladder.
13. A folding ladder according to any one of the preceding claims in which the first and the second stiles form two halves of a longitudinal extending housing, the housing becoming a single closed housing which hides the rungs when the ladder is in the closed position.
14. A folding ladder according to claim 13 in which the housing is square or rectangular in cross section when the ladder is in the closed position.
15. A folding ladder according to any one of the preceding claims in which the rungs are of circular or rectangular cross sectional shape.

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16. A folding ladder according to any one of the preceding claims in which the rungs have grip-enhancing surfaces for affording grip to hands and/or feet of a person ascending or descending the ladder.
17. A folding ladder according to any one of the preceding claims and including releaseable locking means for releaseable locking the ladder in the closed position.
18. A folding ladder according to claim 17 in which the releaseable locking means is a hand-releaseable catch.
19. A folding ladder according to any one of the preceding claims and including a foot engageable member for use in opening and closing the ladder.
20. A folding ladder according to claim 19 in which the foot-engageable member is a lever.
21. A folding ladder substantially as herein described with reference to Figures 1-6 or Figures 7-8 of the accompanying drawings.