FR2574667A1 - System for the emergency evacuation of people located in a multistorey building - Google Patents

Abstract

Evacuation system comprising a carriage 12 which moves along the track 14 and has a pinion 100 which meshes by rotation on the rack 38. A pair of support elements is held on the opposing sides of the track 14 and these support elements are articulated on the carriage 12 in such a way that the pinion 100 comes into contact with the rack 38, the support elements not touching the corresponding sides of the track, and when the pinion 100 is completely engaged in the track 14, the support elements are pushed in an elastic manner into contact with the internal face 42a, 42b of the track 14. A speed-adjusting mechanism is provided for adjusting the speed of rotation of the pinion 100 in the rack 38. During an emergency, the user is put into a harness which is joined to the carriage 12.

Description

EMERGENCY EVACUATION SYSTEM FOR PEOPLE
LOCATED IN A PLUS THMEUBULE @ EURS
Stalls
The present invention relates, in general, to an emergency evacuation system for people located in a multi-storey building, and more particularly to an emergency evacuation system which automatically and slowly descends a user to on the ground f along a path neatly arranged on @n the exterior wall of the building
For the purpose of providing exit means for occupants above a fire which has declared themselves in a multi-storey building, one or more escape stairs usable in the event of fire are frequently provided for. the exterior @ r of the immme @ ble. @ a @ Fortunately, such fire escape stairs are not popular with builders for a number of reasons. First, fire escape stairs are considered unsightly and incompatible with modern architecture; Second, fire escape stairs are expensive and frequently require some maintenance. Third, fire escape stairs can provide easy access to unwanted intruders. Adding fire escape stairs to an old building can not only be difficult, and more often than not impossible, but dangerous for workers trying to install it.

 In order to overcome the problems associated with fire escape stairs, a number of other emergency evacuation systems have been described. One of these systems, in the U.S. patent

 n @ 4 121 689, comprises a motorized rail mounted vertically and a rack disposed inside this rail. A suspension device can be inserted into the rail to engage the rack and gently lower a person installed in the suspension device. A motorized ascent and descent device using a carriage located on a U-shaped beam is described in US Pat. Nos. 2,647,675 and 3,207,263. Various other gravity descent devices have been described, comprising the following device: in front of a zig-zag path described in US Pat. No. 4,125,172 and a conveyor having a brake which is engaged with a vertical cylindrical column or the like described in US Patent No. 3,715,011. Descent devices Motorized which descend a carrier monkey engaged on a roller chain or a helical screw have also been described in US Pat. Nos. 3,831,711 and No. 3 @ 44,021.

Another type of evacuation device of the prior art engages on a ca @ le on a rope. For example, a slow descent mechanism fixed on a rope described in the patent
US 3,946,989 is used to slowly lower the user to the ground by means of a hydraulic braking device. Other speed regulators for rope systems are described in the patents
US 3 861 n97 and n 4 093 186. Next to these devices placed transversely on a hanging rope or a cable, an evacuation device described in the patent
US No. 4,063,615, comprises a drum around which a cahle is slowly derotiled to lower the user to the ground.

 Is also described in the prior art according to the @revet .S. No. 3,348,632, a qiti safety device is used as a climbing aid. This safety device is contained on the side of an H-rail which is mounted next to a ladder. safety is attached to the user and moves freely along the rail in it as the user goes up or down along the ladder As the user comes to slide from the ladder, the sudden movement of the fall causes the safety device to securely grip the rail at 14 and prevents the user from falling lower.

A roller assembly that engages an inverted horizontal T-rail and supports a hanging hoop is also described in U.S. Patent No. 4,271,927.

The roller assembly has two articulated arms that can be released or locked in place from a central point of articulation
There are a number of drawbacks associated with evacuation devices such as those described above. For example, the raceway or rail on which certain devices run is abnormally complicated and costly to manufacture. In addition, some of these rails require special fastenings to the walls and special openings for access to the descent device. A drawback of rope or cable devices is that it is difficult to make a cabal which can be used at all bearings and under these conditions a multitude of cables available for each bearing is usually necessary.

According to the present invention, an emergency evacuation system operated by gravity for a multi-storey building is produced. The evacuation system comprises a longitudinal raceway which is arranged vertically and away from a wall of the building. The raceway has an inner face and an outer face having a rack disposed along its center. A carriage designed to move along the raceway is also available. The carriage comprises a pinion which engages by rotation on the rack and a pair of support elements which are engaged with the horizontal sides. opposite sides of the inside of the rack. Preferably, the support elements are articulated on the carriage so as to release the respective sides of the race track at the moment when the pinion is brought into contact with the rack, and then to elastically push the support element into contact. on the inside of the raceway after the pinion is fully engaged in the rack. A speed adjustment means is connected to the pinion and regulates the speed of rotation of the pinion and thus the speed of the carriage relative to the path of rolling. In operation, the user is installed in a harness which is connected to the carriage and the carriage is then located on the rolling path and slowly lowers the user to a safe place.

 In the preferred embodiment of the present invention, the articulation axis of each of the support elements is more ready than any part of a support element corresponding to two vertical planes which is perpendicular to the wall and which passes through the vertical center line of the interior facade. With this construction, the torque caused around the articulation axis by each support element engaged with the interior face pushes each support element against the vertical central line of the interior face. The pinion is also arranged ati center of the carriage and a second pair of articulated support elements on the carriage is also provided so that the carriage can operate with one or both of the ends in the high position.

 According to the preferred embodiment of the present invention, the speed adjusting means comprises a first hydraulic brake associated with the pinion. In addition, the speed control means also includes a second hydraulic brake associated in the same way with the pinion. your two brakes serve as an additional safety mechanism carriage.

 One of the aims of the present invention is to provide an emergency evacuation system which is easily accessible to the occupants of all the floors of a multi-storey building.

 One of the features of the present invention is that the cart used to lower the user to the ground can be securely and easily attached to the vertically developing raceway. Another feature, in addition, of the present invention is that the movement of the carriage is effected by gravity so that no external source of energy is required.

 One of the advantages of the present invention resides in that the "nacelle" (that is to say the assembly formed by the carriage and the harness) can be stored in a small space and can be immediately ready for use.

 An alite advantage of the present invention is based on the fact that during the descent of the carriage, the latter requires no intervention so that the unconscious or injured person can be lowered without supervision.

 Other objects, features and advantages of the present invention are set forth or appear in a detailed description of a presently preferred embodiment of the invention set out below.

 Figure 1 is a perspective view of an emergency evacuation system according to the present invention.

 FIG. 2 is an exploded perspective view of the carriage shown in FIG. 1.

 FIG. 3 is a top and top view of the carriage shown in FIG. 2.

 FIG. 4 is completely face-on, in section by part and in elevation of the charint at shown in FIG.

 Referring now to the drawings in which the same numbers represent the same elements throughout the various figures, a presently preferred embodiment of the emergency evacuation system 10 is described in Figure 1. The emergency evacuation system 10 comprises a carriage 12 qL: i circulates along a specially designed raceway 14. The raceway 14 is arranged vertically along a wall 16 of a multi-story building. The raceway 14 is also located adjacent to an emergency exit from the interior of the multi-storey building such as a balcony 18.

Provided near the emergency exit, it has a balcony 18, is a storage cabinet 20 in which iine pluralitd of carriages 12 are stored ready for use. The balcony 18 and the storage cabinet 20 are preferably locked and remote switches which are accessible to the emergency evacuation personnel are provided to unlock the balcony 10 and the storage cabinet 20 during 'an emergency situation.

 As shown in Figure 1, a harness clip 22 is attached to the carriage 12. Also associated with the harness clip 22 is a harness 24, such as a parachute harness or the like. The user is installed in the harness 24 and is shown descending slowly by means of the carriage 12 moving along the raceway 14.

 The carriage 12 and the raceway 14 are shown in more detail in Figures 2, 3, and 4. As shown, the raceway 14 has a T-beam 28 which is securely attached to the wall 16 by anchors 30. Securely attached to the central portion of the T-beam 28 is a specially designed beam 32 having a central longitiidinaie groove 34 and cant faces 36a and 36h. Located in an irremovable manner in the groove 34 is a rack 38 whose teeth 40 turn their backs on the wall 16. The beam 32 has inner faces 42a and 42h and outer faces 44a and 44h.

 The carriage 12 comprises two symmetrical halves, the elements of which will be identified by the use of the corresponding figures having a suffix a oll rr according to the half with which this particular element is assembled. For convenience, the elements of one half or the other can be described in detail while the corresponding elements are simply identified in the drawings by the corresponding numbers and suffixes. As shown in Figures 2, 3 and 4, the carriage 12 comprises symmetrical housings 48a and 48b having handles 50a and 50b. The housings 48a and 48b are assembled by means of spacers 52 and 54 in which screws 56a, 56b and 58a, 58b are respectively screwed. As better represented in FIG. 2, the housing 48h contains a chamber 60h.

 In the center of the casing 48b and below the chamber 60b is a bearing 62b comprising a cylindrical orifice 64b. As shown, the corresponding cylindrical orifice 64a extends into a larger cylindrical orifice 66a. In the cylindrical orifice 66a is a transfer pump 68a with a fixed rotor comprising a rotor 70a and a pump body 72a mounted eccentrically. The space between the inner periphery of the pump body 72a and the outer periphery of the rotor 70a constitutes a pumping chamber 74a. Two orifices 76a and 78a are provided on the opposite sides of the cylindrical orifice 64a so as to connect the chamber 70a with the pumping chamber 74a. The cylindrical orifice 66a is closed by a cap 8na which is held in place by screws 82a. A seal 84a is provided around the cylindrical orifice 66a between the cap 80a and the housing 48a.

 The rotor 70a is provided with a central orifice 86a and two small slots 83a and 90a. A shaft 92 extends through a bearing 62a and a cylindrical orifice 64a as far as an orifice 86a. The longitudinal ends of the shaft 92 are also provided with slots 84a and 96a which follow the shape of the slots 88a and 90a respectively. slots 88a and 94a form a cylindrical orifice into which a key 98a is slid, so that the shaft 92 and the rotor 70a rotate as a whole. A similar key, not shown, is also slid into the coupling slots 90a and 96a.

 A pinion 400 is fixedly mounted on the shaft 92. The pinion 100 has teeth 102 which mesh with the teeth 40 of the rack 38. It will be appreciated that when the pinion 100 meshes with the rack 38, the rotation of the pinion 100 puts the pumps 68a and 68h in operation - - as will be explained below.

 As best shown in Figures 2 and 3, grooves 104b and 106b are provided on the opposite sides of the shaft 92 at the bottom of the housing 48b. Contained in the grooves 104h and 105h, respectively, there are suitable supporting elements such as the pads 108b and 110b. The pads 108h and 110h are designed to engage on the inner face 42b of the beam 32 and to slide there slowly throughout. The pads 108b and 110b are respectively subject to the grooves 104b and 106b and are made of a material suitably resistant to wear.

 Articulated on the casings 48a and 48b are pawls 114a and 114h. As shown in FIG. 2, the pawl 114b is articulated on the opposite sides of the casing 48b, through the arms 116h and 118h.

The arms 116b and 118b are respectively contained in the grooves 120h and 122h. As shown, each groove is provided with an external hole 124h and 126h respectively, and with a tapped external hole 128b and 130b. The arms 116b and 118b are fixed in rotation to the casing 48b by the screws 132b and 134b which are received respectively in the bores 136h and 138h provided respectively at the ends of the arms 116b and 1180). A hairpin spring 140b is provided for pitching the '7ras 11 65 and 118b to pivot respectively around the screws 132h and 134b, towards the raceway 14. As shown in Figure 2, the hairpin spring 140h passes around the screw 134b and its free ends engage in the upper part of the groove 122b. The other end of the pin spring 140h is folded back behind the arm 1181) and is put: in engagement with the surface of 118b furthest from the raceway 14. In this way, the pin springs 140b elastically push the pawl 114b to the raceway 14.

 The pawl 114b also includes a base 142h developing between the arms 116h and 118b. The base 142b has a flat surface 144h on which suitable support elements such as the shoe 146b are fixed. As shown in FIG. 2, the shoe 146b is fixed contiguously to the arm 116 @, and another shoe 146b (not shown) is fixed in a similar position contiguous to the arm 118b. As shown in FIG. 3, the pads 146a and 146h are arranged to engage and move by sliding ati along the outer faces 44a and 44b of the beam 32b.

We will also note the other vertical axis. articulation 148a is closer to the vertical plane perpendicular to mid 16 when it passes through the center of the path 14 than any other part of the skid 146h. The reason for this provision is set out below. The blase 142h is also provided with a sloping face 1 50b and a rounded edge 152h.

 In operation, the emergency evacuation system 10 operates in the following manner. Initially, when an emergency arises, most floors of the building can be evacuated normally by the use of stairs or the like. However, in some cases, one or more stages cannot be evacuated in the normal manner. In this case, the emergency evacuation system 10 is used. the emergency evacuation system 10 is implemented by security personnel and under their authority. Initially, the switch, which is conveniently located on the main floor and placed under the staff is operated to release the locks located on the storage cabinets 20 which are located on the floors which must be evacuated by the use of the emergency evacuation system 10. Preferably, this switch also releases the locks located on the balcony 18 or on another storage cabinet 20 or on another emergency exit close to a storage cabinet 20. Then, using communication systems available on each level of the building, instructions are given to the occupants to use the emergency evacuation system 10, comprising instructions specifying: nil are the storage cabinets 20 and the emergency exits such as the balconies 18.

 In the storage cabinet 20 is a plurality of carriages 12 to which the associated harnesses 24 are connected by harness clips 22. Being directed towards the balcony 18 which is used as an emergency exit, the user puts on the harness 24 while standing on balcony 18 until emergency evacuation system 10 is ready for use. The carriage 12 is then ms in place on the raceway 14 by the user. Once the carriage 12 is in place, the user spans the balcony 18 and lets the carriage 12 bear its weight.

Depending on the weight of the user, the carriage 12 moves slowly along the raceway 14 to the bottom, in a safe position.

 Descending the user, the carriage 12 operates in the following manner. Initially, the user grips the carriage 12 by the handles 50a and 50b and aligns the carriage 12 so that the bases 142a and 142h are practically parallel and contiguous with the canted faces 36a and 36b respectively, of the track 14 It will be noted that the carriage 12 operates regardless of which end is located in the high position so that the designations a and b are used only in an identification bit.

The carriage 12 being balanced above the raceway 14, the user then pushes the carriage 12 against the raceway 14. When this occurs, the cant faces 150a and 150b, respectively, of the cli quiets 114a and 114h, touch the corresponding cant faces 36a and 36i. This causes the pawls 114a and 114b to oppose the force of the pin springs such as the pin spring 140h and to pivot to a position such as that shown by the dotted line in Figure 3. the edges 152a and 152h reciprocally release the canted faces 36a and 36h, the pawls 114a and 114b are pushed back towards the position described in FIG. 3. In this position, the pads 108a, 108b, 110a and 110b are pushed into contact corresponding faces 44a and 44b of the beam 32. In addition, the pinion 100 is forced into position when the teeth 102 mesh with the teeth 40 of the raceway 38.

 After the carriage 12 has been placed on the raceway 14, the weight of the user drives rearward on the handles 50a and 50S at the moment when the user spans the balcony 18. In function of the end of the carriage 12 which is in the battered position, for example the end described in FIG. 3, the weight of the user causes the pads 146a and 146b to bear respectively on the inside of the faces 42a and 42b, the beam 32, while the pads 110a and îîOb, bear, respectively on the outer faces 44a and 44b of the beam 32.

It will be noted that the clearance provided between the pads 110 and 146 is sufficiently low to ensure that the teeth 102 of the pinion 100 remain meshed with the teeth 40 of the rack 38.

 As the shoe 146b is pushed into contact with the internal face 42b, a moment is created around the axis of articulation 148b of the pawl 114b. The direction of rotation of this moment depends on the relative positions of the hinge pin 148b and the engagement surface of the shoe 146b relative to a vertical plane which is perpendicular to the wall 16 and which passes through the center of the carriage. 12. By designing the carriage 12 so that the hinge pin 148 is closer, the moment can always act to push the pawl 114b into the engagement position on the raceway 14. Consequently, the greater the weight exercised on the handles 59a and 50b is important, the more the pawls 114a and 114b are pushed to maintain the engagement position on the raceway 14 and to keep the carriage 12 on this same raceway. Naturally, in the absence of weight exerted on the carriage 12, only the pin springs such as the pin spring 140b hold the pawls 114a and 114h in place so that it is easy to set up the carriage 12 stir the raceway 14.

 As the carriage 12 supports the weight of the user, the carriage 12 begins to move down the path 14 when the pads 110a, 110, 146a and 146 ') slide along the raceway 14. This brings about the pinion 100 to rotate relative to the raceway 14 aii moment the teeth 112 eng @ enent silr the teeth 40 of the rack 38. As the pinion 100 rotates, the shaft 92 rotates in the same way and turning causes the rotors 70a and 70b of the hydraulic pumps 68a and 68b to turn. Note that before storage, the chambers 60a and 60b have been filled to the appropriate level of hydraulic fluid which should not change over time. Therefore, when the rotor 7Ca rotates, an eccentrically mounted pump body 72a rotates similarly under the effect: of the gear of its coupling teeth. When the pump body 72a rotates, the hydraulic fluid contained in the chamber 60a is periodically pumped by the pump 68a through the orifices 76a and 78a. During: the operation of the pump 68a, one or other of the orifices 76a and 7Ba is used as an inlet orifice while the other orifice is used as the outlet orifice.

Whether orifice 76a or 78a is used as the inlet orifice depends on the direction of movement of the carriage 12 along the raceway 14. In all circumstances, the size of the smallest orifice, in this embodiment the orifice 78a, regulates the quantity of fluid which can be flowed through it and thus the speed of rotation at which the pump 68a and therefore the rotor 70a operates. Therefore, when the carriage 12 moves along the rolling path 14 under the effect of the weight of the user, the carriage 12 moves at a predetermined speed to slowly lower the user to a safe place.

 Note that the hydraulic pumps 68a and 68h operate as additional brakes to the movement of the carriage 12. Normally, the pumps 68a and 68b operate together to slow the movement of the carriage 12. However, a malfunction occurs if one of the pumps, the other pump is capable of operating alone to slow the operation of the carriage 12 along the raceway 14.

 It will also be appreciated that even if the hydraulic pumps 68a and 68b have been described as fixed rotor transfer pumps, a piston system or a vane pump can also be used to achieve the same goal. The main concern is that a fixed transfer pump transferring a precise quantity of fluid regulated by a flow control device must be provided.

 It will no doubt be appreciated that the installation of the storage cabinet 20 on the balcony 18 is simply a possibility of development. When the emergency evacuation system 10 is used in an office building, a locked central storage area can be provided at each landing level to contain a cart for each employee. In a hurdle building in which the windows are locked, the use of the emergency evacuation system could probably be more appropriate, and especially if balconies are not normally built on the construction. In apartments and hotels, the one-bedroom balcony would not normally be centrally locked. However, a locked cabinet or other suitable part of the room could be reserved to store the cart for each occupant. Other storage or outlet areas can also be considered.

 While the present invention has been described in terms of one of its embodiments taken as an example, those skilled in the art will understand that variants and modifications can be made with respect to the embodiment taken as an example within the framework of the invention and in its spirit.

Claims (16)

Claims  1. Emergency evacuation system (10) activated by gravity for a multistage immeulile, characterized in that it comprises  a longitudinal raceway (14-) disposed vertically and away from a wall t16) of the building, said raceway having an inner face (42a, 42b) directed towards the wall and an outer face (44a , 44h) points towards the outside of the wall:  a rack (38) disposed in the center of said outer face (44a, 44b) along said raceway (14);  a carriage (12) which moves along said raceway comprising a pinion (100) which meshes by rotation on said rack (38), a pair of support elements (10Ba, 108b) which are engaged on the horizontal sides opposite to said inner face (42a, 42b), and an articulation means for each of said support elements (lOBa, 108b) intended to rotate them horizontally without staining the corresponding side of said inner face on moment when said pinion (100) is brought into contact with said rack (38) and thus elastically push each of said support elements (10Sa, 108h)) in support contact on the corresponding sides of said face interior (42a, 42b) after said pinion (100) engages fully on said raceway (14) so that said pinion is held in said raceway (14);  speed adjusting means operatively connected to said pinion (100) for adjusting the speed of rotation and therefore the speed of said carriage (12) relative to said raceway;  means for attaching (22) the harness (24) to said carriage (12) for mooring a user installed in a harness (24) fixed to said carriage (12) during an emergency, whereby said carriage ( 12) is then fixed on the track and slowly descends the user in a safe place.  2. Emergency evacuation system (10) according to claim 1, characterized in that during use, the axis of articulation of each of said support elements is closer than any other part of said corresponding support element with respect to a vertical plane which is perpendicular to the wall (16) and which passes through the li a vertical center of said interior face so that the miming exerted around the articulation axis caused by each of said support elements meshing on said inner face pushes each of said support elements towards the vertical central line of said inner face.  3. Emergency evacuation system (10) according to claim 2, characterized in that said pinion (100) is disposed in the center of said carriage (12) and further comprises a second pair of support means which is also fixed to said articulation means so that one pair of support means is located above said pinion (100) and that the other pair of support means is located below said pinion (100) so that the carriage (12) operates regardless of the end which is in the high position.  4. Emergency evacuation system (10) according to claim 3, characterized in that said articulation means comprises a pair of latching elements (114a, 114h) on which the corresponding ponant elements of said pairs of support elements (146a, 1461)) are mounted, each of said latching elements (114a, 114b) having an overhanging face in contact with the corresponding side of said raceway when said pinion is inserted in said raceway and brings the snap-in elements (114a, 114b) and the support elements to pivot outwards relative to said: raceway  12 until said pinion (100) is completely  engaged siir laditc rack (33) and that it is released  then on said sides so that said elements  support pivot inwards in position on the  said inner face (142a, 142b).  5. Emergency evacuation system (10) according to 1a  claim 4, earactérisé in that it comprises  in addition to external support elements located sensitive-  opposite to said internal support elements  laughers who are in contact with the inner surface,  said external support elements being arranged  so as to be in contact with the outer surface  in order to make a second bearing contact with said  raceway to maintain safely  said pinion in said raceway.  6. Emergency evacuation system (10) according to the  claim 5, characterized in that said elements  supports are pads (108a, 108b, 146a, 146b) which  slide along said raceway (14).  7. Emergency evacuation system (10) saion la  claim 5, characterized in that the means of  speed adjustment includes a first brake hvdrau-  lique in relation to said pinion.  8. Emergency evacuation system (10) according to the  claim 7, characterized in that said means of  speed adjustment further includes a second brake  hydraulically connected to said pinion and which serves as a means of  additional safety braking on said trolley.  9. Emergency evacuation system (10) according to the  claim 7, characterized in that said path of  bearing (14) comprising said inner face (42a,  42) and said outer face (44a, 44b) having a  horizontal section of substantially trapezoidal shape,  said inner face (42a, 42b) being: wide folds that  that of said outer face (44a, 44b).  10. Emergency evacuation system (10) according to claim 2 characterized in that it comprises in otitre a locked storage area located at each level of the building, now containing a plurality of said carriages (12) and a remotely controlled unlocking means for unlocking said storage area located at each level comprising a control switch located so as to be accessible to emergency evacuation personnel and under their authority.  11. Emergency evacuation system (10) according to claim 10, characterized in that it further comprises a locked outlet situated at each level adjacent to said raceway (14) and an unlocking means controlled by polishing distance unlock said outlet when said storage area located on this landing is unlocked and comprising: a control switch located near said operating switch for the storage area.  12. emergency evacuation system (10) according to claim 8, characterized in that it further comprises a locked storage area at each level of the building containing a plurality of said carriages and an unlocking means remotely controlled to unlock said storage area located at each level comprising a control switch located so as to be accessible to emergency evacuation personnel and placed under their authority.  13. Emergency evacuation system (10) according to claim 12, characterized in that it further comprises a locked output situde at each level adjacent to said raceway and a remotely controlled unlocking means for unlocking said output when said storage area located at this level is unlocked and includes a control switch located near said control interriptor of the storage area  14.Emergency evacuation system (10) operated by gravity for a multi-storey building provided with a longitudinal raceway (14) arranged vertically and away from a wall (16) of the building and having an inner face (42e, 42b) of the raceway and an outer face (44a, 44b) of the raceway provided with a central rack (38) over its entire length, the evacuation device being characterized in that He understands  a carriage (12) which moves along the raceway (14) comprising a housing (48a, 48b), a pinion (100) located inside said housing (48a, 48b) which engages by rotation on the rack (38), a pair of support elements (146a, 146b) which are engaged with the horizontal sides opposite to the inner face of the raceway (14), and an articulation means for each element d support in order to pivot each of said support elements horizontally (146a, 146b) to release the corresponding side of the raceway (14) when said pinion (100) is brought into contact with the free rack and for then push elastically each of said support elements in contact with the corresponding sides of the inner face (42a, 42F) of the raceway (14) after said pinion (100) has fully meshed with the rack (30) so that said pinion is there  means for adjusting the speed, optionally connected to said pinion (100) and located in said casing (48a, 48b) for adjusting the speed of rotation of said pinion (100) and therefore the speed of said carriage (12) relative to the path bearing (14): and  means for attaching (22) the harness to said casing (48a, 48b) for mooring a user installed in a harness (24) to said trolley (19) tending to an emergency, whereby said trolley is then fixed on the path bearing (14) and gently lowers the user to a safe place.  15. Emergency evacuation system (10) according to claim 14 operated by gravity for a multi-storey building, characterized in that said speed adjustment means comprises a first hydraulic brake connected to said pinion and a second hy brake - hydraulics connected to said pinion (100) so that an additional means of adjusting the speed is achieved.  16. Emergency evacuation system (10) according to claim 15, characterized in that F during operation F the axis of articulation of each of said support elements (108a, 108b, 146a, 146b) is closer than any other part of said corresponding supporting element of a vertical plane which is perpendicular to the wall (16) and which passes through the vertical center line of the interior face (42a, 42b), so that the moment exerted on the articulation axis caused by said corresponding support elements, in engagement with the interior face, polishes said support elements towards the vertical central line of the interior face.