WO2000040831A1

WO2000040831A1 - Improved emergency escape apparatus

Info

Publication number: WO2000040831A1
Application number: PCT/GB1999/004443
Authority: WO
Inventors: Aubrey Melville
Original assignee: Aubrey Melville
Priority date: 1998-12-31
Filing date: 1999-12-29
Publication date: 2000-07-13
Also published as: GB9828806D0; AU1883000A

Abstract

An emergency escape apparatus for enabling escape from a building or other structure which is designed to be fitted to the outside of a building or other structure close to a window or other above ground exit point. The emergency escape apparatus comprising a linearly extendable ladder attached to support means. The ladder is provided with mechanical actuation means for extending the ladder such that the extent of extension of the ladder is controllable and reversible.

Description

IMPROVED EMERGENCY ESCAPE APPARATUS

This invention relates to improved emergency escape apparatus. Particularly but not exclusively it relates to improvements in the fire escape apparatus disclosed in Patent Document GB-B-2222848 (Melville) .

The known apparatus, disclosed in GB-B-2222848, provides an escape ladder arrangement which may be activated either manually or automatically. The known apparatus includes a hatch which, in the closed position, bears the weight of a rope ladder folded in concertina fashion. To release the ladder (for escape from a building) it is necessary to release the hatch. This in turn allows the ladder to unfurl under its own weight to extend downwards and provide an escape route. To avoid burglary, etc, after use, the ladder can be rewound and the hatch closed again. However, this known arrangement has associated problems. For example, there is the requirement for a hatch which may be cumbersome and awkward to release effectively, particularly in an emergency situation. Furthermore, the ladder cannot be re-used without special treatment to fold it into the "start" position again. A more serious problem is that, because of the necessary folding of the ladder, on release the ladder may become tangled. This can result in the ladder not falling under its own weight and no escape from the building being possible.

It would be desirable to have emergency escape apparatus which does not rely on the ladder falling under its own weight to allow escape from the building or other structure.

According to the present invention there is provided emergency escape apparatus for enabling escape from a building or other structure, the emergency escape apparatus comprising support means for attaching the escape apparatus to the exterior of a building or other structure, a linearly extendable ladder attached to the support means and mechanical actuation means for extending the ladder such that the extent of extension of the ladder is controllable and reversible.

Preferably the mechanical actuation means comprises an electrical motor connected to a drive shaft.

Preferably, the ladder comprises a plurality of rungs, each rung being attached to adjacent rungs by means of at least one expandable connector, for varying the distance between said rungs, all of said rungs being interconnected by means of at least one flexible connector of a predetermined length greater than the length of the ladder when fully contracted, a first end of the at least one flexible connector being connected to a reel fixed on the support means, such that, when the ladder is contracted, a proportion of the flexible connector is stored on the reel, and a proportion of the flexible connector is threaded through holes in each of said rungs and a second end of the at least one flexible connector being fixedly attached to the bottom most rung of the ladder, and wherein, the ladder is expanded by engaging the mechanical actuation means to unravel the at least one flexible connector from its reel, said flexible connector moving through the holes in the rungs to allow the expandable connectors to expand and cause the ladder to extend.

Preferably the at least one flexible connector is made from steel wire.

Preferably said holes in the rungs are substantially concentric.

Optionally, said flexible connector is made from a non- flammable plastic.

Preferably, said expandable connectors comprise an articulated joint comprised of two rigid pieces hinged in the middle.

Preferably, each of said rungs are connected to adjacent rungs by means of two expandable connectors.

Optionally, the articulated joint is spring loaded.

Preferably, the at least one reel is rotatably mounted on the drive shaft of said electric motor.

Preferably, the support means further comprises a casing in which the mechanical actuation means and ladder are contained, the casing having top, front and bottom surfaces, the front and bottom surfaces being connected by hinges, said surfaces of said container being held in place by means of a latch with a release mechanism, the latch connecting the front surface of the casing to the top surface, such that when the release mechanism of the latch is actuated, the front and bottom surfaces of the casing rotate about their hinges allowing the casing to be opened and the ladder to be extended.

Preferably, the latch release mechanism is controlled using an electrical control circuit which provides a control signal to the latch release mechanism causing the latch to open.

Optionally, the latch has a release mechanism comprising a metal spring held in a compressed state by the action of an electromagnet, such that, when the current to the electromagnet is switched off, the spring is released, and the latch is opened.

Preferably, the emergency escape apparatus is further provided with a handle piece connected to said support means which, when the emergency escape apparatus is in use extends out of the top of the emergency escape apparatus and is rotatable about a substantially horizontal axis and for storage inside the casing.

Preferably, the ladder sides are made of a flexible material and the mechanical actuation means contains release means supported by the support means, the release means having an end of the ladder attached thereto, such that the ladder is stored wound around the release means and the ladder is released by operating the release means to unwind the ladder from the release means.

Preferably the release means has a substantially tubular structure. This allows for convenient winding of the ladder around the release means. Preferably the electric motor is fitted with a brake unit. This gives greater control in adjusting the position of the ladder with respect to ground level.

Preferably the end of the ladder adjacent ground level is weighted. This increases the speed of release of the ladder from the wound position.

Preferably, the emergency escape is connected to a fire alarm and/or intruder alarm system and is activated automatically when the fire alarm or intruder alarm is activated.

Preferably optional features of the apparatus may be as described in GB-B-2222848. For example, the apparatus may be fitted with alarm means as described therein, or may be sunken into the body of the building or other structure to lie flush with an external wall thereof.

The invention will now be described by way of example only with reference to the accompanying drawings in which: -

Fig. 1 is a perspective view of an embodiment of the present invention, with the ladder in the fully unwound position;

Fig.2 is a side view of the release means of the apparatus of Figs 1, with internal components shown;

Fig.3 shows a perspective view of a box for containing the apparatus in situ; Figs. 4A and 4B show a perspective view and a side view respectively of a release mechanism for the box shown in Fig . 3 ;

Fig.5 is a perspective view of a second embodiment of the present invention;

Figs . 6A and 6B are perspective views of the handle piece.

Fig. 7A, is an enlarged perspective view of the ladder rungs and the expandable connectors between adjacent rungs, Fig 7B is a side view of one of the expandable connectors;

Fig. 8 is an enlarged side view of a ladder rung;

Fig.9 is a front elevation of the second embodiment of the present invention; and

Fig. 10 is a schematic diagram of an automatic system for activating the emergency escape; and

Fig.11 shows a spring loaded articulated joint.

Referring to the accompanying drawings, apparatus in accordance with a first embodiment of the present invention is generally denoted by reference numeral 10.

The apparatus 10 includes a pair of support brackets 12a, 12b which are each provided with holes 14 for attaching the brackets 12a, 12b to the exterior wall of a building 41 Fig. 3 Fig. IB adjacent a window. The brackets 12a, 12b are metal plates, each having a large aperture 16a, 16b in the centre thereof. In this embodiment, the release means consist of a tubular electric motor and brake unit 18 which extends between the two support brackets 12a, 12b, through the central apertures 16a, 16b and is supported thereby.

A flexible ladder 20 is provided, bolted to the portion of the tubular electric motor and brake unit 18 between the brackets 12a, 12b, by means of conventional bolts 22. The ladder 20 has sides 23 made of rope with wooden rungs 21, making the sides flexible. In this embodiment the lowermost rung 24 of the ladder 20 is weighted for improved operation as will be described below. The ladder sides may also be made of plastic, metal or other fire resistant flexible material.

The components of the tubular electric motor and brake unit 18 can be seen more clearly in Fig 2. Primarily the tubular electric motor and brake unit 18 consists of a tube portion 26, which is of circular cross- section and has diameter approximately 70mm. At either end of the tube 26 are provided electrical connections 28 into which a power supply (not shown) is connected.

Inside the tube 26 in Fig 2, there is provided an 560 tubular motor 32 connected to a differential combined with a drive wheel 34, in turn connected to a support 36 and a connecting shaft 30 which runs to the end of the tube 26. At the end of the tube 26 (the right end as viewed in Fig 2) is provided a 24v DC brake mechanism 38 combined with a support bracket. It will be appreciated that the relative positions of these various components may be changed in other embodiments of the invention. The position of the brake unit will depend on the position of the apparatus in relation to the window once the apparatus is fitted to the building. It is desirable that the brake unit is fitted at the side of the apparatus adjacent to the window or egress.

When installed, and prior to use, the ladder 20 is stored wound around the tube 26. A protective casing shown in Fig. 3 may be provided around the apparatus, although this is not essential.

To operate the apparatus, for example in the event of an emergency, it is necessary to release the brake in the brake mechanism 38. This allows the motor to turn the tube (in the direction of arrow A in Fig 1) so that the ladder 20 is unwound and lowered towards ground level . The extra weight on the lowermost rung 24 increases the speed of lowering of the ladder. Once the desired length of ladder has been lowered, the user can stop the motor by activating the brake mechanism 38 and climb out of the window and down the ladder to safety. Alternatively, the brake unit 38 can be set to activate when the entire length of ladder has been unwound (i.e. when the position shown in Fig 1 is reached) .

In this example, the brake mechanism 38 is fitted with an actuator 40 for manual operation. However, in other embodiments the brake unit may be controlled remotely, for example by infra red, or may be fitted with a smoke detector such that the brake is automatically released in the presence of smoke, caused by a fire. Such systems as those disclosed in GB-B-2222848 may be modified for use with the device of the present invention.

Conveniently, after use, the ladder may be rewound either manually, or by shifting the motor into a reverse mode. In this way the ladder 20 can be safely re-used.

As stated above, the emergency escape apparatus can be stored in a box situated on the side of the building. Fig. 3 shows such a box 42 fitted to the wall of a building or the like. The front panel 48 extends along the top of the box as shown in Fig. 3. The front of the box is provided with a hinge 43 and a further hinge 45 to connect it to the bottom panel 46 of the box. Similarly, the bottom panel of the box is provided with a hinged connection at the point where it meets the wall of the building or the like. The top panel of the box 50 is also hinged at the wall. This hinge is provided with a spring mechanism (not shown) to allow the top panel to spring upwards to point in a substantially vertical direction when the box is opened. The box 42 can be made of steel, plastic or other durable material and contains a latch 44 for opening and closing the box. In particular, the box could be made from a one piece GRP moulding or by Pressure Assisted Forming in polyethylene or polypropylene material . Its primary purpose is to ensure that the emergency escape apparatus remains clean and dry.

Figs. 4A and 4B show in detail the release mechanism of the latch used to open the box 42. In this case, the release mechanism comprises a housing 52 attached to the lower surface of the top section of the box 50. The housing 52 contains a spring attached to an electromagnet 54 connected to an electric circuit (not shown) . A connecting member 56 with a cone shaped head is attached to side 48 of the box so as to fit inside the housing and to abut against the spring 58. In use, the connecting member 56 is clipped inside the housing 52, securing the front of the box. When it is desired to open the box 42 to release the emergency escape, current to the electromagnet 54 is interrupted causing the tension in the spring 58 to be released forcing the connecting member 56 out from the housing 52. This causes the front 48 and the bottom 46 to drop under their own weight to hang vertically below the ladder against the wall as can be seen in Fig. 5 which contains front and bottom panels as shown in Fig. 3.

Fig. 5 shows an embodiment of the present invention in which a second type of linearly extendable ladder is shown. The box has two separate compartments, a left hand one which holds the extendable ladder and a right hand one which holds the motor as shown in Fig. 9. Figs. 7A, 7B, 8 and 9 provide a detailed view of the component parts of the ladder and its operation.

Figs 6A and 6B show a rotatable handle piece 47 which is stored in the box 42 when not in use and is designed to be rotatable about two pivot points contained inside the slots 39 on the bracket 37 used to attach the apparatus to the wall. In this case, the pivot points are lined up so as to allow the handle piece to rotate substantially vertically. The handle piece is used to give a hand-hold to a person climbing out of a window onto the emergency escape. In Figs 6A and 6B, the box and ladder have been omitted from the drawings to allow them to show the handle piece in its retracted position Fig 6A and in the extended position Fig. 6B.

In use, the person wishing to use the emergency escape reaches out of the window 33 located above the apparatus in this example, and pulls the handle piece 47 up towards them. The handle piece 47 rotates about the substantially horizontal axis of the pivots. When the handle piece 47 is substantially vertical, the slots move downwards over the pivot point and fix the handle piece in place.

Figure 7A shows two rungs of a ladder 61 and 62, rung 61 being the bottom most rung. The rungs are made from metal, such as mild steel or aluminium and are designed so that adjacent rungs fit snugly together to minimise the amount of space taken up by the ladder when stored in a box such as the box shown in Fig. 3. Holes 63 have been cut out from each of the rungs in order to make them lighter. In addition, a bright or luminous strip 72 is situated on the front of each rung. This strip can be of adhesive tape or can be painted on to the front surface of the rung 62.

Adjacent rungs are joined together by means of expandable connectors 64 located one at either side of a rung and formed by an articulated joint. In this embodiment, the expandable connectors 64 are formed by two substantially identical separate metal pieces which are pinned together in the middle to form a hinge 69. The hinged joint allows the space between adjacent rungs to be expanded and contracted. As can be seen from Fig 7A, the connectors are designed so that the two pieces of the connector fold inwardly towards the centre of the step. The connectors are designed so that the hinge 69 does not extend fully so that there is an angle between the two halves of the connector when the ladder is fully extended.

The rungs of the ladder are also provided with holes in which a collar or grommet 70 is formed through which a high tensile flexible steel wire 68 can be threaded. High tensile steel wire is used as it is flexible, strong and fire resistant. Other ropes or wires which have the requisite flexibility, strength and fire resistance can be used such as some types of plastic ropes . The holes on each side of the rungs are substantially concentric with one another. The collar 70 has a diameter larger than that of the steel wire 68 so as to allow the steel wire 68 to move smoothly through the collar 70. The bottom most rung of the ladder 61 is provided with a stopper 66 attached to the steel wire 68 and is weighted. The stopper prevents the bottom rung from becoming unthreaded.

As can be seen in Fig. 9, the ladder is extended and retracted by means of the steel wire 68 threaded through the collars 70 on each side of each rung. The steel wire is coiled onto a pair of reels 80. The reels 80 are mounted on a drive shaft 82. The end of the drive shaft provides a driving bar 86 which has a helically indented surface that is designed to fit into the teeth of a cog wheel 84. The cog wheel is mounted on a shaft 87, attached to a gear box and motor 88 mounted in a bracket 90, which is attached to a device 92 used to reverse the direction of the motor. This is used to allow the ladder to be extended and retracted. In addition, the actuator 40 as shown in Fig. 2 can be added to the embodiment of Figs 5 to 9 to provide a means of manually unwinding the steel wire from the reels 80.

In use, when an emergency occurs, the box 42 containing the emergency escape system can be opened simply by interrupting the current to the electromagnet as described above which releases the electrically operated latch. This type of latch may be actuated in a variety of ways for example:

manual actuation through a switch, hard wired to the latch; manual actuation through a switch, the switch providing a microwave signal to the emergency escape which opens the latch; automatic actuation controlled by a control unit with a variety of inputs; automatic actuation controlled by a fire alarm; automatic actuation controlled by a smoke detector; automatic actuation controlled by an intruder alarm; actuation by remote control through a telephone link; and actuation by remote control through a cellular phone link direct to the emergency escape.

Where cabling is used to actuate the emergency escape apparatus, it should have fire resistant cladding.

The box then opens as described above in relation to Figs. 4A and 4B .

At this stage, the ladder 96 is in its fully retracted position. In this position, the rungs of the ladder fit together and are connected by a short length of steel wire 68. The action of opening the box causes the motor 88 to be switched on. The motor 88 turns the cog 84 which rotates the driving bar on the drive shaft which unravels the steel wire 68 from the spool 80. As the steel wire is unravelled, the distance between each rung of the ladder increases to a maximum. This maximum distance is defined by the maximum angle subtended by the two parts of each expandable connector 64.

The lowering of the ladder 96 can be seen in Fig.9. The space 100 between the top two rungs of the ladder has increased to the maximum allowable as defined by the angle subtended by the expandable connector 64. As can be seen, the space between the second and third rungs 102 is increasing, but is not at a maximum. The space between the third and fourth rungs 104 is the smallest of the three. In general, the ladder rungs become spaced from the top until the ladder is fully extended to the ground. The ladder may be easily retracted by reversing the direction of the motor. In which case the bottom rung is pulled up to meet the next bottom rung and so on until the ladder is fully retracted.

A further advantage of the second embodiment of the present invention is that the length of the ladder may be increased or decreased simply by adding or removing component rungs 61 and connectors 64 and by adjusting the amount of steel wire used.

An automatic control unit for the present invention is shown in Fig. 10. Fig 10 is a schematic diagram of the control unit of the present invention. Such a unit is housed in a box made of metal or from injection moulded plastic, formed in two parts. The box as is indicated generally at 110 contains, movement detectors 112 connected to an alarm system 114 which is electrically connected to the escape apparatus and also contains an LCD screen. The control unit can also be connected to the telephone network for remote activation of the emergency escape system.

Smoke detectors and/or a fire alarm 120 are also electrically connected to the emergency escape apparatus. Fig. 10 also includes a button 126 which can be pressed to activate the system manually. In use, the system, once activated in one of the three ways described above, trips a switch (not shown) which causes the current in the electromagnet to be interrupted. This causes the container 42 to open as described above. In addition, the motor which unravels the steel wire 68 from its reel 80 is activated by the same switch and causes the ladder to be lowered.

In a further embodiment of the present invention, the hinges of the articulated joints each contain a circular spring 130 Fig. 11 which is wound and kept under tension when the ladder is in its fully contracted position. In use, when the steel wire 68 is unravelled, the springs actively increase the angle between the legs of the articulated member to a maximum value.

The embodiments described above have many significant advantages over known emergency escape systems. For example, with the apparatus of this embodiment, it is possible to easily adjust the height of the lowermost end of the ladder (and not "drop" the whole ladder as with known arrangements) , without any danger of the ladder becoming entangled, thereby ensuring safe and quick escape from the building in an emergency situation. The escape apparatus can be retro-fitted to existing buildings with ease.

Modification and improvements may be made to the foregoing without departing from the scope of the invention.

Claims

1. An emergency escape apparatus for enabling escape from a building or other structure, the emergency escape apparatus comprising support means for attaching the escape apparatus to the exterior of a building or other structure, a linearly extendable ladder attached to the support means and mechanical actuation means for extending the ladder such that the extent of extension of the ladder is controllable and reversible.

2. An emergency escape apparatus as claimed in Claim 1 in which the mechanical actuation means comprises an electrical motor connected to a drive shaft.

3. An emergency escape apparatus as claimed in Claim 1 or Claim 2 in which the ladder comprises a plurality of rungs, each rung being attached to adjacent rungs by means of at least one expandable connector, for varying the distance between said rungs, all of said rungs being interconnected by means of at least one flexible connector of a predetermined length greater than the length of the ladder when fully contracted, a first end of the at least one flexible connector being connected to a reel fixed on the support means, such that, when the ladder is contracted, a proportion of the flexible connector is stored on the reel, and a proportion of the flexible connector is threaded through holes in each of said rungs and a second end of the at least one flexible connector being fixedly attached to the bottom most rung of the ladder, and wherein, the ladder is expanded by engaging the mechanical actuation means to unravel the at least one flexible connector from its reel, said flexible connector moving through the holes in the rungs to allow the expandable connectors to expand and cause the ladder to extend.

4. An emergency escape apparatus as claimed in Claim 3 in which the least one flexible connector is made from steel wire.

5. An emergency escape apparatus as claimed in Claim 3 or Claim 4 in which said holes in the rungs are substantially concentric.

6. An emergency escape apparatus as claimed in any of Claims 3 to 5 in which the at least one flexible connector is made from a non-flammable plastic.

7. An emergency escape apparatus as claimed in any of Claims 3 to 6 in which said expandable connectors comprise an articulated joint comprised of two rigid pieces hinged in the middle.

8. An emergency escape apparatus as claimed in any of Claims 3 to 7 in which each of said rungs are connected to adjacent rungs by means of two expandable connectors.

9. An emergency escape apparatus as claimed in any of Claims 3 to 8 in which the articulated joint is spring loaded.

10. An emergency escape apparatus as claimed in any of Claims 3 to 9 in which the at least one reel is rotatably mounted on the drive shaft of said electric motor.

11. An emergency escape apparatus as claimed in any of the preceding Claims in which the support means further comprises a casing in which the mechanical actuation means and ladder are contained, the casing having top, front and bottom surfaces, the front and bottom surfaces being connected by hinges, said surfaces of said container being held in place by means of a latch with a release mechanism, the latch connecting the front surface of the casing to the top surface, such that when the release mechanism of the latch is actuated, the front and bottom surfaces of the casing rotate about their hinges allowing the casing to be opened and the ladder to be extended.

12. An emergency escape apparatus as claimed in Claim 11 in which the latch release mechanism is controlled using an electrical control circuit which provides a control signal to the latch release mechanism causing the latch to open.

13. An emergency escape apparatus as claimed in Claims 11 or 12 in which the latch release mechanism comprises a metal spring held in a compressed state by the action of an electromagnet, such that, when the current to the electromagnet is switched off by the electrical control circuit, the spring is released, and the latch is opened.

14. An emergency escape apparatus as claimed in any of the preceding Claims in which the emergency escape apparatus is further provided with a handle piece connected to said support means which, when the emergency escape apparatus is in use extends out of the top of the emergency escape apparatus and is rotatable about a substantially horizontal axis and for storage inside the casing.

15. An emergency escape apparatus as claimed in Claim 1 or Claim 2 in which, the ladder sides are made of a flexible material and the mechanical actuation means contains release means supported by the support means, the release means having an end of the ladder attached thereto, such that the ladder is stored wound around the release means and the ladder is released by operating the release means to unwind the ladder from the release means.

16. An emergency escape apparatus as claimed in any of Claims 1, 2, and 15 in which the release means has a substantially tubular structure.

17. An emergency escape apparatus as claimed in any of Claims 1, 2, 15, and 16 in which the electric motor is fitted with a brake unit.

18. An emergency escape apparatus as claimed in any preceding Claim in which the end of the ladder adjacent ground level is weighted.

19. An emergency escape apparatus as claimed in any preceding Claim in which the emergency escape is connected to a fire alarm and/or intruder alarm system and is activated automatically when the fire alarm or intruder alarm is activated.