the device shown in fig1 comprises a balloon 1 which is filled with a gas lighter than air . the balloon 1 is movable along a cable 2 of which one end is connected to a secure location 3 and the other end is connected to an evacuating location 4 . guide means 5 , 6 are connected on either side of the balloon for guiding the balloon between the secure location 3 and the evacuating location 4 . transport means 7 are connected to the bottom side of the balloon 1 , by means of which persons 8 can be transported from the evacuating location 4 to the secure location 3 . the transport means 7 are provided to carry a weight which is sufficient to make the balloon 1 descend . this sufficient weight is the weight of n persons , so that the balloon 1 descends when the number of persons on the transport means 7 is n or more and ascends when the number of persons is less than n . in the device of fig1 , n equals three , but n may also be more or less . in this way , the descent results from the total weight of the balloon 1 , guide means 5 , 6 , transport means 7 and n or more persons 8 being larger than the lifting force of the gas in the balloon . as the balloon 1 can still ascend if the number of persons 8 on the transport means 7 is below n , a person can also be transported with the balloon from the secure location to the evacuating location . this is advantageous in evacuating operations on a building on fire , as this makes it possible to transport one or more firemen up to the evacuating location , who can assist in the evacuation or help to extinguish fire . the guide means connected to the balloon 1 comprise propellers 5 and guide wires 6 . the propellers 5 are preferably provided to be driven by means of pressurized air , which can for example be supplied from an air bottle carried by a fireman on the transport means , or from an air supply on the ground via an air duct . the propellers may however also be electrically driven , the electricity then being supplied by a battery connected to the propellers or from the ground , or they may be driven in any other way known to the person skilled in the art . the guide wires 6 have a substantial length , so that they can be held by a person on the ground , who can apply additional steering to the balloon by pulling or releasing the guide wires 6 . by means of the guide wires 6 , it can also be ensured that the balloon 1 descends safely to the ground in case the cable 2 should break or unintentionally come loose from the evacuating location 4 . the device shown in fig1 further comprises a vehicle 9 , by means of which the device can be transported to a place where evacuation is needed in a short time . the vehicle 9 is preferably provided with inflation means ( not shown ) for inflating the balloon and a winch ( not shown ) for rolling up and veering the cable 2 . in the detail of the device shown in fig2 it can be seen that the balloon 1 is provided to move along the cable by means of a wheel 10 , which is preferably provided with a brake ( not shown ) by means of which the speed with which the balloon 1 travels along the cable 2 can be limited . in this way , the safety of the persons 8 being evacuated can be enhanced . the transport means 7 preferably comprise a bar 11 which is hung from the balloon 1 with a set of wires 12 . from the bar , a number of belts 13 are hung , by means of which the persons 8 to be evacuated can be connected to the balloon 1 . the guide wires 6 are preferably connected to the ends of the bar 11 . the transport means may however also be constructed in any other way known to the person skilled in the art . if necessary , for example for evacuating a wounded person , a stretcher can be attached to the transport means . the balloon 1 preferably has a shape comprising a flat side 14 and a convex side 15 , as shown in fig3 . the flat side 14 is preferably substantially oval , as is shown in fig2 . this shape of the balloon 1 makes it possible to bring the transport means 7 very near to a building , so that a firemen can easily connect the cable 2 to the evacuating location 4 after the first ascent of the balloon 1 and so that the connecting of persons 8 to the balloon 1 is facilitated . the flat side 14 is preferably constructed in a rigid and inflammable material , for example kevlar or other , so that the risk of the flat side 14 catching fire or being damaged is reduced . the balloon 1 is preferably divided into a number of compartments ( not shown ), so that a sufficient amount of gas remains in the balloon even if one of the compartments has sprung a leak . the flat side 14 preferably has rounded edges in order to reduce the risk that the balloon gets stuck behind an obstruction on the side wall of the building . the gas used for inflating the balloon 1 is preferably an inert gas , preferably helium , which is preferably supplied from bottles on the vehicle 9 . the use of an inert gas has the advantage that the device of the invention can be used in explosion endangered environments , as such a gas is substantially not liable to chemical reactions . the gas used for inflating the balloon may however also be any other gas lighter than air known to the person skilled in the art . preferably , a smaller balloon ( not shown ) is connected to the balloon 1 by means of a rope . this smaller balloon is helpful in determining the direction of the wind and as such in maneuvering the balloon 1 . the device according to the invention , shown in fig1 – 3 is preferably operated as follows , for example for evacuating persons from a building on fire . the vehicle 9 is driven to a secure location 3 near the building , but preferably at a certain distance from the side wall of the building . then , the balloon 1 is inflated , a fireman takes place on the transport means 7 and the balloon is let up by veering the cable 2 . during this first ascent of the balloon , the balloon 1 is in a fixed relationship with the cable 2 , which can for example be obtained by means of the brake on the wheel 10 or by providing a stop or knot ( not shown ) on the cable . the balloon 1 is guided to the evacuating location 4 by operating the propellers 5 and the guide wires 6 during ascent of the balloon 1 . once the evacuating location 4 is reached , the fireman gains access to the building , for example by breaking a window with a hammer . the firemen then installs a prop 16 on the evacuating location 4 , for example between the floor and the ceiling of the storey of the building on which he is located . he then connects the cable 2 to the prop . at this point , evacuation of persons from the evacuating location can start . this is conducted by placing a number of persons 8 on the transport means 7 , for example by closing the belts 13 underneath the armpits of the persons 8 as shown in fig2 , after which the brake is released , so that the balloon 1 descends along the cable 2 as a result of the weight put on the balloon being larger than the lifting force of the gas . as the balloon 1 can now travel along the cable 2 , substantially no steering is required during descent of the balloon 1 . once the balloon has reached the secure location 3 , the persons 8 are removed from the transport means 7 , after which the balloon 1 is ready to ascend back to the evacuating location 4 , so that more persons can be evacuated . during the first ascent , preferably only a single fireman is placed on the transport means . in this way , a quick ascent can be ensured , so that the fireman arrives at the evacuating location after only a short period of time . preferably , this first fireman remains at the evacuating location to assist the persons to be evacuated in taking place on the transport means 7 . in this way the whole of the transport means 7 is vacated for evacuating persons . during the second ascent , preferably a second fireman is transported to the evacuating location 4 . this second fireman can also assist the persons 8 in taking place on the transport means 7 . when the number of persons 8 on the transport means 7 is below n , the balloon can also be made to descend by pulling it towards the secure location 3 with the guide wires 6 , or by disconnecting the cable 2 from the evacuating location 4 and hauling it in . in this way , also the last persons 8 present on the evacuating location 4 can be evacuated with the device of the invention , even if their number is below n .
device for evacuating persons , for example from a multi - storey building on fire , from an evacuating location to a secure location , comprising : a balloon provided to be filled with a gas lighter than air for moving the balloon between the secure location and the evacuating location ; guide means connected to the balloon for guiding the balloon between the secure location and the evacuating location ; and transport means connected to the balloon for transporting persons from the evacuating location to the secure location ; wherein the device further comprises a cable provided to be connected between the secure location and the evacuating location and that the balloon is provided to be movably mounted on the cable between the secure location and the evacuating location .