JPS5677492 | HANGING LADDER |
FORKES ANDREW (GB)
DAVIES JORGE (GB)
FORKES ANDREW (GB)
DAVIES JORGE (GB)
WO1990003487A1 | 1990-04-05 |
GB191222407A | 1913-10-02 | |||
US5779000A | 1998-07-14 | |||
US5372217A | 1994-12-13 | |||
US6102155A | 2000-08-15 | |||
US7004287B1 | 2006-02-28 | |||
US1612126A | 1926-12-28 | |||
GB2235717A | 1991-03-13 |
CLAIMS
1. An escape ladder unit comprising a housing and collapsible ladder, the ladder comprising a plurality of rungs connected by flexible connection means, the housing being arranged to store the ladder and comprising at least one running track, wherein the rungs are adapted to cooperate with the running track such that the or each running track provides a guide for the deployment of the rungs from the housing.
2. An escape ladder unit according to claim 1 which is adapted to fit at least partially within the cavity of a cavity wall.
3. An escape ladder unit according to claim 1 or claim 2 in which the ladder is arranged such that the rungs are arranged in a single stack within the housing.
4. An escape ladder unit according to any preceding claim in which the housing comprises a ladder ejection means arranged to support the weight of the ladder during deployment.
5. An escape ladder unit according to any preceding claim in which the ladder is deployed from the top of the housing.
6. An escape ladder unit according to any preceding claim in which the ladder comprises a weight arranged to assist deployment of the ladder.
7. An escape ladder unit according to any preceding claim in which the rungs comprise grooves arranged to house the flexible connection means when the ladder is in its collapsed state.
8. An escape ladder unit according to any preceding claim which comprises a barrier arranged to provide a surface for deployment of the ladder.
9. An escape ladder unit according to claim 8 in which the barrier is arranged to be stored within the housing.
10. An escape ladder unit according to claim 8 or claim 9 in which the barrier is arranged to be deployed prior to the ladder.
11. An escape ladder unit according to any of claims 8 to 10 in which the barrier is a length of flexible material suitable to provide a fire blanket
12. An escape ladder unit according to claim 11 in which the fire blanket comprises a flame resistant material and/or coating.
13. An escape ladder unit according to any of claims 8 to 12 in which the barrier is arranged to provide a visual alert means
14. An escape ladder unit according to any of claims 8 to 13 in which the barrier comprises a first section of material and a second section of material, the first section being arranged to provide a smooth running surface to aid in the deployment of the ladder.
15. An escape ladder unit according to any of claims 8 to 14 in which the barrier comprises a weight arranged to assist in the deployment of the barrier under gravity.
16. An escape ladder unit according to any preceding claim in which the unit is arranged to cooperate with a window fitting.
17. An escape ladder unit according to any preceding claim in which the ladder is stored in a first portion of the housing and the barrier is stored in a second portion of the housing.
18. An escape ladder unit according to any preceding claim which comprises a mounting means arranged to allow the unit to be attached to or mounted on a wall.
19. An escape ladder unit according to claim 18 in which the mounting means is arranged to allow the position of the unit to be adjusted with respect to the mounting means.
20. A building comprising at least one double-skinned wall, the wall comprising an inner wall portion and outer wall portion, the wall portions being substantially parallel but spaced from one another, the wall comprising a portal and an escape ladder unit according to any preceding claim, wherein the escape ladder unit is arranged at least partially in the space between the wall portions and in the vicinity of the portal.
21. A building according to claim 20 in which the portal comprises a window and/or a door.
22. A building according to claim 20 or 21 in which the wall portions may comprise one of: brick work, block work, stud work.
23. A building according to any of claims 20 to 22 in which the gap between the walls is roughly 50mm.
24. A building according to any of claims 20 to 23 in which the ladder is arranged, in use, to be passed through the portal.
25. A building according to any of claims 20 to 24 in which the portal comprises a frame and the escape ladder unit is arranged to be accessed through a portion of the frame.
26. A building according to claim 25 in which a portion of the frame forms part of the escape ladder unit.
27. An escape ladder unit substantially as described herein and as illustrated in the accompanying Figures.
28. A building substantially as described herein and as illustrated in the accompanying Figures. |
ESCAPE LADDER UNIT
This invention relates to generally to escape ladder units and more particularly to collapsible escape ladder units.
Ladders can be used as a means of escape from an upper floor of a building in the event of fire. Typical prior art ladders include rigid, fixed ladders which are secured to a building near a window or fire escape door. In some embodiments, these have a lower section which is counterbalanced or otherwise generally raised from the ground to prevent access from the ground to the fire escape door or window. However, these ladders still present a security risk.
Alternatively, rope ladders have been used. These have the advantage that they can be easily stored when not in use and are not generally accessible from the ground. However, rope ladders are prone to tangling and may be stored away in a manner which means they are not readily accessible in the event of a fire.
US7004287 in the name of James Barbara describes a safety ladder which is stored in a box intended to be attached to a building beneath a window. The ladder can be deployed as necessary to provide an escape from the building.
According to a first aspect of the invention, there is provided an escape ladder unit comprising a housing and collapsible ladder, the ladder comprising a plurality of rungs connected by flexible connection means, the housing being arranged to store the ladder and comprising at least one running track, wherein the rungs are adapted to cooperate with the running track such that the or each running track provides a guide for the deployment of the rungs from the housing.
This is advantageous as it allows the ladder to be smoothly deployed. In particular, rope ladders can suffer from the problem that they become tangled as they are deployed. By providing a running track, the rungs are deployed one at a time, reducing the risk of tangling during deployment.
In one embodiment, the unit is adapted to fit at least partially, or wholly, within the cavity of a cavity wall. This is advantageous as it provides a fixed storage place for the unit such that the unit will be accessible in an emergency.
In a preferred embodiment, the ladder is arranged such that the rungs are arranged in a single stack within the housing. This will further reduce the risk of tangling during deployment. Further, in embodiments where the unit is at least partially within a cavity, the width of the unit will be limited. Providing a single stack of rungs in such embodiments means that the rungs can be substantially the width of the cavity (which at present in the UK, is generally a standard width of 50mm or above), thus providing the widest possible step and making the ladder easier to descend and/or climb. Generally, the rungs may be perhaps 35mm wide which enables them, to fit within the housing.
In a preferred embodiment, the housing comprises a ladder ejection means arranged to support the weight of the ladder during deployment. This is advantageous as it reduces or removes the need for manual strength in deploying the ladder. The ladder ejection means may be resiliently mounted and/or counter weighted or the like.
In some embodiments, the ladder may be deployed from the top of the housing. In such embodiments, the ladder ejection means may be arranged to assist in deployment of the ladder by providing an upward thrust.
In one embodiment, the ladder comprises a weight arranged to assist deployment of the ladder. The weight may comprise a rung of the ladder. For example, the weight may comprise die cast metal. Providing such a weight is advantageous as the weight could be deployed before the body of the ladder and could be used to effect or assist the deployment of the ladder under gravity.
Advantageously, the rungs may be arranged to house the flexible connection means when the ladder is in its collapsed state. For example, the rungs may comprise grooves. This allows the ladder to be packed into a smaller volume than would otherwise be possible. In addition, housing the flexible connection means in a groove may reduce the risk of tangling.
In one embodiment, the unit comprises a barrier arranged to provide a surface for deployment of the ladder. In a preferred embodiment, the barrier is arranged to be stored within the housing. In such embodiments, the barrier may be arranged to be deployed prior to the ladder. This is advantageous as it provides a running surface for the ladder.
In one embodiment, the barrier is a length of flexible material suitable to provide a fire blanket. A fire blanket advantageously provides a barrier between flames from the building and a person on the ladder. In particular, upper floor windows are often vertically above lower floor windows and in the event of a fire there is a risk that flames could reach out from a lower floor window. Therefore, in some embodiments, the barrier or fire blanket is arranged to extend past any lower floor windows and, in one embodiment, to the ground.
In a preferred embodiment, the fire blanket comprises a flame resistant material and/or coating. In a particular embodiment, the fire blanket is arranged to provide a visual alert means. For example, the blanket may be brightly coloured and/or display written messages asking for assistance. This will bring attention to the fact that an emergency situation is underway.
In one embodiment, the barrier or blanket may comprise a first section of material and a second section of material, the first section being arranged to provide a smooth running surface to aid in the deployment of the ladder. This is advantageous as, as will be appreciated from the foregoing, the blanket can act both to assist the smooth deployment of the ladder and to protect the ladder and/or a person thereon from flames. Thus, different sections of the ladder may have different properties in order to best perform the role of that section. For example, the first section may comprise a plastic coating to reduce its friction coefficient. Alternatively or additionally, the first section may comprise a material arranged to form an arc over a window sill or the like, rather than conforming to the shape or the sill. The material may be such that it substantially holds its own shape once deployed, for example comprising a rubber substrate. Alternatively or additionally, the first section may be somewhat thicker and/or stiffer than the second section. This may assist the smooth deployment of the ladder as it will smooth the contours of the sill or other surface over which it is draped. It will be appreciated that both the surface material and the stiffness can
contribute independently or in combination to the 'smoothness' of the blanket or barrier as a running surface.
The barrier may comprise a weight arranged to assist in the deployment of the barrier under gravity. This is a convenient means to cause deployment of the barrier.
In a preferred embodiment, the unit is arranged to cooperate with a window and/or door fitting. The unit may comprise a cover which forms all or part of a window sill. The cover may be adapted to assist in the deployment of the ladder and/or the barrier, for example by acting as the weight. In such embodiments, the escape means preferably complies with the standards set out in British Building Regulations 2000 and the window and/or door preferably complies with the standards of the emergency egress windows and/or door set out in section B1 of the regulation.
In one embodiment, the ladder is stored in a first portion of the housing and the barrier is stored in a second portion of the housing. This will reduce the risk of the barrier and the ladder becoming tangled. In such embodiments, at least one of the first or second portions may be arranged to fit wholly within the wall cavity.
In one embodiment, the unit comprises a mounting means arranged to allow the unit to be attached to or mounted on a wall. In a preferred embodiment, the mounting means is arranged to allow the position of the unit to be adjusted with respect to the mounting means. This is advantageous as it allows for greater flexibility in the position of unit. Where the unit is, for example, installed within a cavity, providing a mounting means arranged to allow the position of the unit to be adjusted may allow the unit to be more readily aligned with, for example, a window or door frame, as is described in greater detail below.
According to a second aspect of the invention, there is provided a building comprising at least one double-skinned wall, the wall comprising an inner wall portion and outer wall portion, the wall portions being substantially parallel but spaced from one another, the wall further comprising a portal and an escape ladder unit according to the first aspect of the invention and wherein the
escape ladder unit is arranged at least partially, or wholly, in the space between the wall portions and in the vicinity of the portal.
Storing an escape ladder unit in the wall cavity is advantageous as the wall cavity provides a fixed storage point so the unit will not be lost or stored away from the portal. Further, storing the ladder in the vicinity of the portal means it is suitably placed for immediate deployment in the event of an emergency.
The portal may for example comprise a window and/or a doorway. Such portals customarily provide emergency escape points from a building. In a preferred embodiment, the window and/or doorway complies with the standards for emergency egress windows or doorways set out in section B1 of the British Building Regulations 2000.
The one or both the wall portions may comprise brick work or block work walls. One of the wall portions (preferably the inner wall portion) may comprise a stud wall. These are known examples of 'cavity walls'.
In one embodiment, the gap between the walls is at least 50mm. 50mm is the standard gap in a cavity wall in the UK.
In one embodiment, the ladder is arranged, in use, to be passed through the portal.
In one embodiment, the portal comprises a frame and/or a sill and the escape ladder unit is arranged to be accessed and/or deployed through a portion of the frame.
In one embodiment, a portion of the frame and/or sill forms part of the escape ladder unit. For example, it may comprise a cover portion.
Embodiments of the invention are now described, by way of example only, with reference to the accompanying figures of which:
Figure 1 shows an exploded view of an escape ladder unit according to one embodiment of the present invention;
Figure 2 shows a cross section of the escape ladder unit of Figure 1 ;
Figure 3 shows a detailed view of the rungs of the escape ladder unit of Figure 1 ; Figures 4 to 6 show a cut-away view of the escape ladder unit of Figure 1 in situ and through its stages of deployment;
Figure 7 shows an exploded view of an escape ladder unit according to a second embodiment of the invention;
Figure 8 shows a cut-away view of the escape ladder of Figure 7 in situ; and Figures 9 to 11 show a view of the outside of a building as the escape ladder is deployed.
Figure 1 shows an escape ladder unit 100 comprising a collapsible ladder 102, a housing 104, a fire blanket 106, a sill portion 107, a cover 108, and mounting means 110.
The ladder 102 comprises a plurality of rungs 112. Lengths of rope 116 (in this example, galvanised steel wire rope with a plastic covering) connect the rungs 112. The rope 116 passes through holes bored through a region of the ends the rungs 112 and includes a series of stop- knots 202 (shown in Figure 2) which act to keep the rungs 112 at a regular spacing when the ladder 102 is deployed ready for use, connecting the rungs 112 together so as to form a rope ladder. The rope 116 therefore provides a flexible connection means between the rungs 112.
Each of the rungs 112 comprises a groove 114 running along its length (also shown in Figure 2). The rope 116 and the groove 114 are arranged such that lengths of the rope 116 can lie within the groove 114 when the ladder 102 is in its collapsed state. At the end of each rung 112 there is a skidder 118. The skidders 118 comprise plastic elements which are arranged to cooperate with the running track 128 inside the housing 104 as is described in greater detail below.
The ladder 102 further comprises a release handle 120 mounted on a weighted bar 122 (in this case, a die cast iron bar). The weighted bar 122 is attached to one of the end rungs 112 of the ladder 102. The other end rung 112 is secured to the housing 104 via anchor lines 113. The
anchor lines 113 each comprise two lengths of rope, one connected to the end rung and the other connected to the housing 104. The two pieces of rope are detachably linked, in this example by a removable shackle 115. The detachable linkage allows the ladder 102 to be readily installed within the housing 104 and further allows the ladder 102 to be replaced if necessary.
The housing 104 comprises two side portions 124, an end portion 125 and two planar rectangular cover potions 123 arranged to join the side portions 124 so as to define a substantially rectangular box, open at one end defining a portion of the housing 104 in which the ladder is stored. A slotted cover 127 is arranged to fit over the open end. The housing 104 further comprises a fire blanket casing 126 which defines a portion of the housing 104 in which the fire blanket 126 is stored and which is arranged to affix to the surface one of the cover portions 123. The casing 126 comprises a metal material arranged to be plastered over once the until 100 is in situ in a wall.
As is shown in detail in Figure 3, each of the side portions 124 (and, indeed, the end portion 125) comprise a length of box section metal tubing 121 which provides structural strength. The box section tubing 121 fits inside an extruded upvc frame 129 which bears a running track 128 parallel to a surface of the tubing 121. The running track 128 is arranged to lie inside the box and is arranged to retain the skidders 118 at the ends of the rungs 112 so that the skidders 118 (and therefore the rungs 112) can move in the longitudinal axis of the side portions 124 only. As can be best seen from Figure 2, one side of the running track 128 runs substantially the full length of the unit 100 while the other side is shorter to allow for the blanket 106 to be dispensed from the same slot as the ladder 102, as is described in greater detail below.
The end portion 125 comprises a resiliently mounted ladder ejection means in the form of a push bar 130. In this embodiment, the push bar 130 is mounted on sprung support bars, which in turn are mounted through the end portion 125. The arrangement is such that, when the ladder 102 is collapsed inside the housing 104, the push bar 130 is urged against the end portion 125. However, during deployment of the ladder 102, the reliantly mounted push bar 130 will act to push the ladder 102 out of the housing 104, as is described in greater detail below. As will be understood by the skilled person, the force due to the resilience of the fully compressed springs is
substantially equal to the weight of the ladder. As each rung is deployed, the weight of the ladder supported by the push bar 130 reduces at substantially the same rate as the force supplied by the springs reduces, allowing for smooth deployment.
The fire blanket 106 comprises a substantially rectangular length of brightly coloured, fire resistant material such as Nomax®. In this embodiment, and as shown in Figures 10 and 11 , the blanket 106 comprises two sections of material. The first section 902 is arranged to provide a smooth surface as detailed below and therefore comprises a rubberised substrate with a plastics coating. The second section 904 is wider than the casing 126, and its edge portions 906 are folded in. A shape-memory material is sewn into the fold and is arranged such that, when the blanket is deployed, the edge portions 906 unfold. The end of the first section 902 of the fire blanket 106 is fixed to the inside of the cover portion 126 of the housing 104. The blanket 106 passes over the weighted bar 122 at the end of the ladder 102. In this embodiment, the blanket 106 includes a cut-out portion through which the release handle 120 passes. The blanket 106 is fed to the base of the fire blanket casing 126 where the remaining length of blanket 106 is arranged in 'concertina' folds within the casing 126. The free end of the first section of blanket 106 feeds through slot in the slotted cover 127 to protrude outside the housing 104.
The blanket 106 feeds through the sill portion 107 and the free end is then fixed to a cover 108.
The cover 108 comprises a die-cast metal rounded rectangular portion with an affixed handle 109.
As can be best seen in Figure 2, the escape ladder unit 100 may be placed in situ in the cavity of a cavity wall.
A cavity wall is a double skinned wall (usually, in the UK under current practise, the inner wall portion 204 comprises breeze blocks and an outer wall portion 206 comprises house bricks) built with an air gap G within the wall. This gap G is typically at least 50mm wide in the UK and can be
partially or wholly filled with insulating material, although the presence of an air gap G also improves the thermal insulation provided by the wall by itself.
In this embodiment of the invention, the box defining a portion of the housing 104 in which the ladder 102 is stored is suitably sized to fit entirely inside the cavity of a wall. The mounting means 110 is arranged to fix the unit 100 to the wall.
In this example, the mounting means 110 comprise metal brackets which comprise a planar projecting portion arranged to be 'built in' to a joint between courses of bricks during construction of the outer wall portion 206. These will be held in place in the mortar used to construct the wall. The mounting means 110 further comprise vertical slots 111 to which the housing 104 is attached via bolts. The slots allow the vertical position of the housing 104 within the cavity to be adjusted in order to properly align it with a window frame.
The fire blanket casing 126 forms part of the inner wall portion 204 and is again held in place by mortar. As will be appreciated by the skilled person, the inner skin 204 will generally be finished with a layer of plaster or the like and this plaster coating will extend over the casing 126.
The unit 100 is arranged partially within the cavity gap G such that it is below a window frame 210. As will be appreciated, a window frame 210 generally comprises an external sill 212 and an internal sill board 214. In this embodiment, the internal sill board 214 comprises a rectangular slot above the cavity in the wall, which is of a complementary size to receive the sill potion 107 of the unit 100. The slot cover 108 of the unit 100 is arranged within the sill portion
107 to be substantially flush with the surface of the interior sill board 214 and the sill portion 107 provides a smooth, aesthetically pleasing finish to the interior sill board 214.
In the event that use of the ladder 102 becomes necessary (for example, in the event that a fire traps a person in the upstairs rooms of a building 900 such as shown in Figures 9 to 11 ) the escape ladder 102 may be deployed as follows, with reference to Figures 4 to 6 and 9 to 11.
As is shown in Figures 4 and 9, the first step is to open the window 402. The window 402 opens outwards so as not to be in the way of a person deploying the ladder. Further, in this example, the window opens to at least 90° to the building so as not to obstruct deployment of the ladder. Next, the cover 108 is lifted and thrown out of the window 402. As the cover 108 is weighted, it falls towards the ground, pulling the affixed fire blanket 106 behind it. The concertina folds in the blanket 106 allow it to be pulled from the fire blanket casing 126 with minimal resistance and no risk of tangling. The fire blanket 106 continues to be dispensed until substantially the whole length is outside the unit 100, with one fixed end remaining in the housing 104 (see Figures 5 and 10). The upper, rubberised first section 902 of the blanket 106 lies over the window frame 210 and the external sill 212. The length of blanket 106 hanging outside the window 402 is brightly coloured and will therefore attract attention to the fact that an emergency escape is underway. The shape-memory material in the folds of the lower, wider second section 904 of the blanket 106 causes it to unfold such that the edge portions 906 are opened at each side of the lower second section 904.
The next step in deployment of the unit 100 is to pull upwards on the release handle 120, lifting the weighted bar 122 affixed to the end rung 112 of the ladder (see Figures 6 and 11 ). The weighted bar 122 is then released outside the window 402 where its weight causes it to pull the ladder 102 rung 112 by rung 112 from the housing 104 and through the sill portion 107. The deployment of the ladder 102 is further assisted by the action of the reliantly mounted push bar 130, which helps to lift the ladder 102. As each rung 112 is deployed, its skidders 118 run up the running tracks 128 on the inside of the housing 104, both being pushed towards the upper region of the housing 104 by the action of the push bar 130 and being pulled once the previous rung 116 has reached the limit allowed by the length of the rope 112 between adjacent rungs 112.
As both the skidders 118 and the running tracks 128 comprise smooth, hard, plastic materials, there is a low coefficient of friction between two and the skidders are able to slide freely. Providing surfaces with a low coefficient of friction means that the skidder does not have to act as rollers or the like, therefore minimising the number of moving parts which increases reliability of the unit as moving parts tend to fail.
The rubberised plastic-coated upper portion 902 of the blanket 106 provides a smooth running surface for the ladder 102 over the window frame 210 and the external sill 212. The relative stiffness (or ability to hold its own weight) of the material comprising the upper portion 902, causes it to form a smooth arc over the window sill and its smooth surface has a low coefficient of friction.
Figures 7 and 8 show an alternative embodiment in which there is no fire blanket 106. Parts in common with the first embodiment have been labelled with like reference numerals.
In this embodiment, the housing 104 fits entirely within the cavity in the wall. The first rung 112 of the ladder is fixed directly to the cover 108. As described above, and as shown in Figure 8, throwing the cover 108 out of the window 402 causes the ladder 102 to follow, rung 112 by rung 112.
Alternative embodiments exist which do not depart from the scope of the invention. For example, the blanket 106 could also display an appropriate message such as 'HELP - FIRE' or instructions such as 'CALL 999 - EMERGENCY SERVICES. In the embodiments described herein, the unit 100 is built into the walls but in alternative embodiments, the unit could be retrofitted within an existing cavity wall. Although in the embodiment described above, the window 402 opens to at least 90 degrees, in other examples, this may not be the case. For example, the window 402 may open to less than 90 degrees and/or may open in a horizontal rather than a vertical plane. Alternatively or additionally, the window 402 may, for example, be cantilevered or may be arranged to be removed from its frame entirely.
In the embodiment described above, the mounting means 110 comprises metal brackets arranged to be 'built in' to a joint between courses of bricks with vertical slots 111 to which the housing 104 is attached via bolts, the slots 111 allowing the vertical position of the housing 104 within the cavity to be adjusted. However, other mounting means are possible. For example, alternative mounting means may allow the horizontal position to be adjusted (perhaps in addition to the vertical position), and/or may support the unit from below. The mounting means may be
arranged to cooperate with the window or door frame and/or may be bolted to the brick rather than held in the joint between bricks. Alternatively or additionally, the mounting means may comprise a sleeve, for example made from a plastic material, which is installed in a manner similar to a cavity tray, as will be familiar to the person skilled in the art. The sleeve may simply rest on the edge of the wall section(s) which define the lower edge of the window or door space in that wall or could built into the wall between course of bricks. The unit could be lowered into the sleeve after the build has been completed (perhaps before a window frame is installed). This may be advantageous as there would be no risk of obstruction from hardened cement protruding from the face of the wall. In addition, in such an embodiment, the unit could be installed as part of the window installation rather than as part of the building of the house.