EMERGENCY ESCAPE SYSTEM

Abstract: Apparatus for escaping from a personnel containment structure such as a building or a vehicle which has a frangible panel mounted within a wall space of the containment structure. The apparatus comprising trigger means and at least one protractive device for breakin the frangible panel. The protractive device being located proximate to the at least one frangible panel and comprising an electrical input connected to the trigger means, propulsion means connected the electrical input and a solid member. The trigger means providing a signal to the propulsion means via the electrical input to propel the solid member form the protractive device into the frangible panel to break the frangible panel. The invention allows a person trapped in a building or vehicle to escape without having to break the frangible panel using a hammer.

Description: EMERGENCY ESCAPE SYSTEM This invention relates to a means of escape for personnel from an enclosed volume or container in the event that an emergency situation arises which warrants evacuation of the volume. The enclosed volume in question could be either within a static edifice such as a building or a mobile structure such as a vehicle. Common escape routes from such containers are by means of doors, windows (fixed and hinged) and hatches. In the interest of occupant safety there is an increasing trend to provide greater ease of exit from structures such as vehicles or buildings. This has in general resulted in a greater number of exit points. The use of doors as a means of escape is often limited by the geometry of the container structure, as doors are generally larger and heavier than the alternative options and require to be hung on structural supports. Doors are also generally more expensive than the other escape options and can in certain circumstances be regarded as a security problem. The use of windows as an escape route requires that the window itself is hinged or removable such that it provides a sufficiently large exit area. This could require breaking of the glass pane by means of a hammer or similar implement. Breaking of large glass panes manually by means of a break-hammer is physically difficult, especially for children or elderly people. Additionally there are psychological factors which deter people from breaking glass panes with break- hammers. Hinged windows of the size required for use as escape routes can be difficult to open especially where the frames have become distorted through exposure to thermal to mechanical factors. The present invention aims to overcome or to minimise the problems associated with current emergency escape systems. The invention provides apparatus for escaping from a personnel containment structure such as a building or a vehicle which has a frangible panel mounted within a wall space of the containment structure and wherein there is provided trigger means and at least one protractive device for breaking the frangible panel, the protractive device being located proximate to the at least one frangible panel, the protractive device comprising means for coupling the trigger to the protractive device, propulsion means connected to the coupling means and a solid member, the trigger means providing actuation of the propulsion means via the coupling means to propel the solid member from the protractive device into the frangible panel to break the frangible panel . Preferably, the coupling means comprises an electrical input connected from the trigger means to the protractive device. Preferably, the propulsion means is provided by a pyrotechnic charge within a space envelope ignited by a thermally sensitive explosive, connected to the electrical input, ignition of the pyrotechnic charge propelling the solid member towards the frangible panel. Optionally, the propulsion means is provided by a spring held under tension by the force generated by an electromagnet, such that, the spring is released and the solid member propelled towards the frangible panel when the electromagnet is switched off by a signal from the trigger. Optionally, the propulsion means is provided by the force of magnetic repulsion between an electromagnet and a magnetised solid member such that the solid member is propelled towards the frangible panel when the electromagnet is switched on by a signal from the trigger. The propulsion means will provide sufficient kinetic energy to the solid member to cause one or more frangible panel to shatter. Preferably, the solid member consists of a piston. Preferably, the piston is mounted in a chamber. Preferably, the end of the piston that hits the frangible panel is flat . Optionally, the end of the piston that hits the frangible panel is pointed or rounded. Preferably one protractive device is used to break one frangible panel. Optionally, one protractive device is used to break a plurality of frangible panels. Preferably, the protractive device is located at the periphery of the frangible panel such that the solid member impacts one of the two surfaces of the frangible panel. Optionally, the protractive device is located at the periphery of the frangible panel such that the solid member impacts an edge of the frangible panel. Preferably, the frangible panel is coated with a flexible film bonded to one or each of its surfaces to prevent contact with and spread of shards from the frangible panel on breakage by the solid member. Use of the flexible film facilitates safe deployment and removal of the frangible panel from its frame. Preferably, the frangible panel is made from glass. More preferably, the frangible panel is made from toughened safety glass . Optionally, the trigger signal is activated manually by depressing a button, switch or lever. Optionally, the button, switch or lever is situated beside the frangible panel. Optionally, the trigger signal is activated in response to a sensor activated alarm. Further optionally, the sensor activated alarm is connected to a heat detector and/or a smoke detector and/or a deceleration detector and/or an orientation detector. Advantageously, the apparatus has an electronic control and diagnostic system, which checks electrical continuity of the system and determines that sufficient power is available to operate the protractive device. Failure to meet pre-set system requirements will result in operation of a visible and/or audible warning signal that indicates that the system has a fault condition. Optionally, the control system will include a programmed delay in initiation of the protractive device with the option of manual cancellation of its operation. This facility allows activation of the system to be aborted in the event of accidental or malicious operation. Preferably, the system will contain an independent power supply which will remain operable even when external power supplies have been severed. The invention will now be described, by way of example only, with reference to the accompanying drawings, in which: Fig.l is a schematic representation of the protractive device mounted in position facing the frangible panel; Fig.2 is a cross sectional view of a protractive device actuated by a pyrotechnic charge; Fig.3 is a cross sectional view of a protractive device actuated by an electrically controlled coiled spring; Fig.4 is a cross sectional view of a protractive device actuated by an electromagnet ,- Fig.5 is a schematic representation of the protractive device mounted in position facing a pair of parallel frangible panels; Fig.6 is a schematic representation of a pair of protractive devices each mounted in position and each facing one of a pair of frangible panels; Fig.7 is a schematic representation of a pair of protractive devices each mounted end-on to a respective one of a pair of frangible panels; Fig.8 is a schematic representation of a protractive device mounted in position facing a pair of frangible panels and containing a secondary piston arranged in line with the protractive device and located between the panels; Fig.9 is a schematic representation of a protractive device mounted end-on to a pair of frangible panels and containing a secondary piston arranged in line with the protractive device and located below the panels; and Fig.10 is a schematic representation of a system for operating the emergency exit according to one aspect of the present invention. In the following figures, the same reference numerals have been used in different figures where the same type of component is described. Fig. 1 shows means for escaping from a personnel containment structure in accordance with the present invention. This embodiment shows a protractive device 2 located inside a mounting block 6. The mounting block and protractive device are positioned relative to a frangible panel, which, in this example is a glass pane 10 constructed from toughened safety glass. In general, the protractive device is located on the inside of the building, vehicle or the like and comprises a piston 32 (as shown in Figs 2, 3 and 4) contained within a chamber 34. Firing means are provided to propel the piston 32 into the frangible panel so as to cause it to shatter. The protractive device 2 contains electrical connectors 12, used to control actuation of the device. These electrical connectors are attached to control means (see, for example, Fig. 10) The mounting block 6 contains a number of features. In general it is designed to ensure that the protractive device is fitted securely in position beside the window or other frangible panel. In Fig. 1, the mounting block 6 is supported on a vertical member 14 which is itself supported by the wall (not shown) surrounding the window 10. A plate 16 attached to the vertical member 14, is used to contain the inner mounting block 18 that surrounds the front portion of the protractive device 2. The back portion is provided with a retaining cap 19. A vertical plate 20 contains a hole through which the front portion of the protractive device 2 fits. A vertically arranged plate 22 abuts against the glass pane 10 and the protractive device. The member 22 contains a hole through which the piston can move on actuation. The mounting block also contains a back plate 24 containing a spacer to provide a small gap between the glass pane 10 and the surface of the back plate. In other embodiments, this gap is provided by angling the back plate towards the glass pane such that the back plate and glass pane are in contact at a point towards the top of the back plate 24 (see for example Fig.5) . The inner surface of the glass pane 10 as shown in Fig.l is provided with a flexible film bonded or otherwise attached to the surface of the glass. The film is ideally made from an abrasion resistant material. The film is designed to hold together the pieces of glass or other frangible material which are created after the protractive device has been used to shatter the panel, since the pieces of glass or other frangible material remain bonded to the film. The film can be applied to more than one of the surfaces of the glass or other frangible material . Fig. 1 shows the film applied to the inside surface of the glass pane 10. In this case, the film is applied only to the portion of the glass pane above the mounting 6. It will be appreciated that the film could be applied to all the surfaces of the glass or other frangible material in other embodiments of the invention. In cases where there is double glazing or the frangible material is arranged in multiple layers, the flexible film could be applied to any or all of the surfaces. The film can advantageously be applied to the surface of the glass or other frangible material at the inside of the structure and the layer of glass or other frangible material at the outside of the structure. In use, when driven forward by the actuator, the piston 32 strikes the glass pane 10 initiating a shock wave within the glass, which causes it to shatter. The shattered glass above the mounting is held together by the film 7. Gentle application of force to the surface of the glass pane will allow the glass to be removed giving an unobstructed exit with minimum glass debris. Applying the film to the glass above the mounting makes it easier to remove the panel as the glass held in the mounting is not attached to the glass in the mounting 6 after the protractive device has been used. This embodiment of the invention shows the protractive device mounted at the periphery of the window. Peripheral mounting is preferred at the protractive device is easily disguised, easily protected from interference and is easily mounted inside the wall panel. In addition, it does not obscure the view from the window of passengers. Fig. 2 shows a preferred protractive device in which the piston is actuated using a pyrotechnic charge. In this case, a Metron (registered trademark) actuator of the DR2000 series available from ICI Nobel Enterprises. The actuator comprises a hollow body 30 housing a piston rod 32. The piston is slideable within a channel 34 in the actuator body. The piston stroke is typically between 1 and 20mm but in this example is preferably between 1 and 4mm to minimise the size of the actuator. The piston shown in Fig. 2 has a flat end although it may be pointed or otherwise profiled if required. The actuator body is provided with a chamber 36 behind the piston 32. The chamber is lined with the charge cup 38 into which the pyrotechnic 40 is inserted. The pyrotechnic is ignited by means of a hot wire sensitive explosive either pressed on a bridgewire (not shown) or in the form of a fusehead 42. Examples of suitable pyrotechnics for this application are barium styphnate or a mixture of potassium perchlorate with powdered zirconium or titanium metal . The fusehead 42 or alternative bridgewire assembly is mounted on a seal 44 which provides two electrical contacts via which the actuator can be interfaced to the source of electrical power used for initiation. This seal 44 is preferably of the type known as a glass to metal seal. This can optionally be retained in the actuator body 30 by means of solder or suitable adhesive. By this means the seal is able to withstand the internal pressure generated during operation of the protractor. Optionally a retaining cap 19 can also be attached to the rear of the actuate such that it further supports the seal 44 and allows the device to contain higher pressure without release of combustion products. In operation, the piston is driven forward rupturing a weakened septum 48 in the front of the actuator body. The piston has at its head end a deformable seal 46 or o-ring and is held between the piston and a charge cup 12. Alternatively the seal could be held in a groove machined into the piston head. The seal 46 prevents escape of gaseous combustion products when the piston is driven down the bore of the body during operation of the actuator. When driven forward by combustion of the pyrotechnic, the piston strikes the glass pane 10 initiating a shock wave within the glass, which causes it to shatter. The shattered glass will normally be held together by the actions of the plastic film 28. Gentle application of force to the surface of the glass pane will however allow the glass to be removed giving an unobstructed exit with minimum glass debris. Fig. 3 shows a protractive device for use in accordance with the present invention in which the piston 32 is actuated by means of a stiff spring 50 held under tension. The spring is held within a sleeve 52, formed by an electromagnet. The electromagnet is connected to an alternating current power supply (not shown) by means of electrical connectors 12. In use, the piston is actuated by removal of the current to the sleeve 50. This causes the tension in the spring to be released, forcing the piston 32 forward, rupturing the weakened septum 48 in the front of the actuator body and driving the piston into the glass or other frangible material panel. In this example, the piston head 33 is pointed to provide high pressure at the contact point between the piston and the frangible panel. It will be appreciated that a spring, such as that disclosed in Fig. 3 can be held under tension using a moveable lip to prevent release of the spring. The spring tension can be released by moving the lip mechanically. Fig .4 shows a protractive device for use in accordance with the present invention in which the piston 32 is actuated by the use of repulsive magnetic forces. In this example, an electromagnet 58 is attached to an alternating current power supply (not shown) . The electromagnet is configured such that its north pole is facing the piston. In this example, the piston is constructed from a permanent magnet with its north pole arranged adjacent to the electromagnet. In use, the piston is propelled through the channel by repulsive magnetic forces present when current to the electromagnet is switched on. Other types of mechanical and electro-mechanical actuation means may be used to move the piston. Figs. 5- 9 show a number of specific embodiments of the present invention in which at least one protractive device is used in different configurations in order to break the glass or other frangible panel. Fig. 5 shows an escape means in accordance with the present invention. In this example, the mounting block, is similar to that shown in Fig.l, with the exception that it has been lengthened in order to incorporate a double glazing unit comprised of glass panes 10 and 11 separated by a gap. The inside glass pane 10 has the flexible film bonded to its surface facing to the inside of the vehicle, building or the like. In use, the protractive device 2 is used to shatter both glass panes by propelling the piston through the inner glass pane 10 and into the outer pane 11. Fig.6 shows an escape means in accordance with the present invention. The glass panes 10 and 11 are arranged such that the outer pane 11 extends beyond the inner pane 10 as shown. The distance between the bottom surface of the inner glass pane 10 and the bottom edge of the outer glass pane is such that a second protractive device 2a can be accommodated in a modified mounting. The first protractive device 2 is used to shatter the inner glass pane 10 and the second 2a is used to shatter the outer glass pane 11. Fig. 7 shows a further embodiment of the present invention. In this example, the protractive devices arranged to face the end surface of the glass panes 10 and 11. The mounting is therefore modified to fit around the protractive devices 2 and 2a. Glass pane 11 is provided with a flexible film 7a on the outer surface. In use, the protractive devices 2 and 2a cause the glass to shatter by firing their pistons at the bottom surfaces of glass panes 10 and 11 respectively. The presence of the flexible film on both glass panes, as above, allows the glass panes to be easily and safely removed from both sides of the window space. Fig. 8 shows a further embodiment of the present invention. In this example, a single protractive device is used to shatter a double glazing unit by fitting a secondary piston 70 between the glass panes 10 and 11. In use, the protractive device causes its piston 32 to move through and shatter the inner glass pane 10. The energy contained in the piston then causes it to continue moving and to propel the secondary piston into the outer glass pane 11 shattering it. Fig.9 shows an embodiment of the invention in which a secondary piston 72 is connected to a protractive device. The secondary piston has two heads 74 and 76 which are located immediately below the bottom surfaces of glass panes 10 and 11. In use, the protractive device causes its piston 32 to push the secondary piston upwards into the glass panes 10 and 11 causing them to be shattered. As safety and reliability is important, embodiments of the invention can be configured with an additional, back-up protractive device. It will be appreciated that the piston need not hit the frangible material at 90° and can be arranged to hit the frangible material at an acute angle. Figure 10 shows a schematic representation of an example of the invention configured for use in a vehicle such as a bus or coach in which there are a number of emergency escape windows 80 indicated. In this example, the protractive devices 82 are those shown in Fig.2, and are actuated pyrotechnically as described above. The protractive devices are attached to the frame of the window or other suitable mounting block 6 such as shown in Figs.5- 9. The panes 80 may conveniently be of any glass suitable for vehicle windows, however toughened glass is preferred as it is readily shattered into small fragments. A flexible film 7 is advantageously bonded to one or both surfaces of the glass such that it covers the area of the window within the bounds of the frame. On breaking of the glass this film holds the shards together allowing for easy removal of the glass from the frame to give an unobstructed opening. An electronic control unit 90 situated in the drivers consul is used to monitor the status of the circuitry within the exit operating system and to determine that sufficient electrical power is available to operate the actuators on demand. An alarm at the control unit will indicate the presence of any fault in the system allowing maintenance to be undertaken. This control unit can optionally be configured to control a number of exits as shown in Fig.10. A further option is the inclusion of a delay function between system activation's and operation of the actuators. This delay when combined with an alarm at the driver's consul and the option of a manual override or cancellation switch allows the driver to abort operation of the actuators in the event of a malicious or accidental use. An audio and/or visual alarm can also be located beside the protractive device and window. The system will be activated by means of a simple manually operated switch 84 in proximity to the exit. Preferentially there will be secondary electronic operating system 86 associated with each operating switch. This will contain an independent re-chargeable power source, which is trickle charged from the main vehicle battery. This has the benefit that the exit can operate even in the situation where the electrical link to the main vehicle battery has been severed. This secondary system may also be provided with electrical filters to protect the pyrotechnic actuator from pick up of transient electrical signals, which could cause unwanted operation. In addition, the protractive devices can be activated by any one of a number of sensors. These include: Tilt/orientation sensors; Smoke/heat sensors; Movement/deceleration sensors. A connection can be provided to each of the protractive devices either directly or through the electronic control unit 90 to each of the protractive devices 80 so that when any of the above hazards arise, the protractive devices can be triggered. In addition, intelligent control of the protractive devices can be used in conjunction with these sensors. Readings from the tilt/orientation sensor can be used such that where the vehicle has ended up on its side, the windows on the ground are not smashed. Similarly, the heat/smoke sensors can be used such that the windows closest to the source of the heat are not smashed. In addition, the device can be actuated by a switch connected to a power source such as a battery, located beside the protractive device and window. The switch can be located behind a panel of glass as is commonly found in fire alarms. Modification and improvements may be made to the foregoing without departing from the scope of the invention.

Claims: CLAIMS 1. Apparatus for escaping from a personnel containment structure such as a building or a vehicle which has a frangible panel mounted within a wall space of the containment structure and wherein there is provided trigger means and at least one protractive device for breaking the frangible panel, the protractive device being located proximate to the at least one frangible panel, the protractive device comprising means for coupling the trigger to the protractive device, propulsion means connected to the coupling means and a solid member, the trigger means providing actuation of the propulsion means via the coupling means to propel the solid member from the protractive device into the frangible panel to break the frangible panel. 2. Apparatus as claimed in Claim 1, wherein, the coupling means comprises an electrical input connected from the trigger means to the protractive device. 3. Apparatus as claimed in Claim 1 or Claim 2, wherein, the propulsion means is provided by a pyrotechnic charge within a space envelope ignited by a thermally sensitive explosive connected to the electrical input, such that ignition of the pyrotechnic charge propels the solid member towards the frangible panel. 4. Apparatus as claimed in Claim 1 or Claim 2, wherein the propulsion means is provided by a spring held under tension by the force generated by an electromagnet, such that, the spring is released and the solid member propelled towards the frangible panel when the electromagnet is switched off by actuation by the trigger. 5. Apparatus as claimed in Claim 1 or Claim 2, wherein the propulsion means is provided by the force of magnetic repulsion between an electromagnet and a magnetised solid member such that the solid member is propelled towards the frangible panel when the electromagnet is switched on by actuation by the trigger. 6. Apparatus as claimed in any one of the preceding Claims, wherein the propulsion means will provide sufficient kinetic energy to the solid member to cause one or more frangible panel to shatter. 7. Apparatus as claimed in any one of the preceding Claims, wherein the solid member consists of a piston. 8. Apparatus as claimed in Claim 7, wherein the piston is mounted in a chamber. 9. Apparatus as claimed in Claim 7 or Claim 8, wherein the end of the piston that hits the frangible panel is flat. 10. Apparatus as claimed in Claim 7 or Claim 8, wherein the end of the piston that hits the frangible panel is pointed or rounded. 11. Apparatus as claimed in any one of the preceding Claims wherein one protractive device is used to break one frangible panel . 12. Apparatus as claimed in any one of Claims 1 to 10, wherein, one protractive device is used to break a plurality of frangible panels. 13. Apparatus as claimed in any one of the preceding claims, wherein the protractive device is located at the periphery of the frangible panel such that the solid member impacts one of the two surfaces of the frangible panel . 14. Apparatus as claimed in any one of Claims 1 to 12, wherein, the protractive device is located at the periphery of the frangible panel such that the solid member impacts an edge of the frangible panel. 15. Apparatus as claimed in any one of the preceding Claims wherein the frangible panel is coated with a flexible film bonded to one or each of the surfaces of the frangible panel to prevent contact with and spread of shards from the frangible panel on breakage by the solid member. 16. Apparatus as claimed in any one of the preceding Claims wherein the frangible panel is made from glass. 17. Apparatus as claimed in any one of the preceding Claims wherein the frangible panel is made from toughened safety glass. 18 Apparatus as claimed in any one of the preceding Claims, wherein the trigger signal is activated in response to a sensor activated alarm. 19. Apparatus as claimed in any one of the preceding Claims, wherein, the sensor activated alarm is connected to a heat detector and/or a smoke detector and/or a deceleration detector and/or an orientation detector. 20. Apparatus as claimed in any one of the preceding Claims, wherein an electronic control and diagnostic system, checks electrical continuity of the system and determines that sufficient power is available to operate the protractive device. 21. Apparatus as claimed in any one of the preceding Claims, wherein the electronic control and diagnostic system, is connected to an alarm which provides a visible and/or audible warning signal that indicates that the system has a fault. 22. Apparatus as claimed in any one of the preceding Claims, wherein the apparatus contains an independent power supply which remains operable even when external power supplies have been severed. 23. Apparatus as claimed in any one of the preceding Claims, wherein the control system includes a programmed delay in initiation of the protractive device to allow manual cancellation of its operation. 24. Apparatus as claimed in any one of Claims 1 to 17, wherein the trigger signal is activated manually by depressing a button, switch or lever. 25. Apparatus as claimed in Claim 24, wherein the button, switch or lever is situated beside the frangible panel.

Inventors: GRAHAM STEVEN JOHN, YOUNG MARTIN, GRAHAM, STEVEN, JOHN, YOUNG, MARTIN
Applicants: GRAHAM STEVEN JOHN, MCGREGOR YOUNG LIMITED, YOUNG MARTIN, GRAHAM, STEVEN, JOHN, YOUNG, MARTIN
Application year: 2000
Main classification: A62B3
IPC codes: A62B3