EP0230502A2 - Collapsible burglar-proof fire-escape ladder with separate release stations and safety belts with locking arms - Google Patents

Abstract

The invention relates to a collapsible fire-escape ladder with safety belt, of which the side bars (A,S) consist of U-sections and the rungs (W) of a square tube. The rungs are fastened to the side bars by means of articulated connections. At the upper end of the ladder there is a device (J,K) which protects the ladder against theft. One or more separate escape stations or release stations can be installed by sawing through the outer bar (A) and by fastening a freeing pin (O) into the outer bar (A) above the cut. The freeing pin (O) has a collar (R) which replaces the material removed as a result of the sawing operation. The connection between the outer bar (A) and the escape or release stations is made by means of a locking plug (H) which is introduced into a hole in the outer bar (A) and a hole in the freeing pin (O). A safety belt (E) is fastened to the outer bar (A) by means of a blocking arm (B). For this, the blocking arm (B) is inserted into the outer bar (A) either from the upper end of the outer bar or via an insertion slot on the rescue station which corresponds to the width of the blocking arm. The widest blocking arm (B) is provided at the topmost station. Under this, the insertion slots become sequentially narrower so that the blocking arm can slide over the insertion slots located under it. The rungs (W) allow blocking against a swinging-out of the ladder over 90 DEG , in that their ends come into engagement with the walls of the side bars. The wall-fastening clamps (P) which fit with the inner bar (S) and which are fastened to the bar with the same bolt fastenings as for the rungs stabilise the ladder against lateral movement. <IMAGE>

Description

The invention relates to a collapsible fire escape made of metal, which is folded in the normal state and is therefore theft-proof. In the event of a fire, this fire escape can be unfolded by a simple manual process on the part of each escape station to form a fire escape that extends straight down to the ground and is equipped with guides for locking arms with seat belts.

The seat belt is attached to one of the conductor side rails using its locking arm. These locking arms are designed so that they slide down the side rail in the unloaded state, block when loaded by the weight of a person on the side rail, and thus ensure that the person does not fall off the ladder.

It is known that there are certain safety requirements associated with fire escape routes for houses with two or more floors. This problem is often raised by facilities such as e.g. Fire escape ropes, rope ladders or a robust ladder with safety rings, which is permanently attached to the outside of the building, solved.

However, climbing a rope requires good training and it is usually too late to consider this aspect once the fire has broken out. In addition, climbing on a swinging rope ladder requires good physical condition and strong nerves, while the safety of stationary fire escapes equipped with safety rings is questionable if a person loses hand or foot support in a state of panic. That means there is a real risk of falling through the ladder like in a shaft. In addition, such ladders represent unsightly elements on house fronts.

Different types of fire escapes are known.

The conductor described in US-A-4,245,717 consists of separate sections for each floor. In the event of an escape situation, the house occupant on the upper floor of the house must first release his own ladder section. If the occupant has climbed onto this section, he must then loosen the ladder section on the floor below. This can be done by leaning down while holding on to one hand to loosen the next section of ladder, or by trying to find the trigger with his foot.

In this way, the person fleeing must descend, floor by floor, or ladder down cut around ladder section. It is obvious that such a descent is risky, and especially if it is dark and the person must grope around on each floor to find the trigger. Furthermore, this ladder has different cross struts between the steps that hinder the descent. Furthermore, this ladder has no safety equipment that prevents a person from falling down when losing hand or foot hold.

US-A-3 414 081 describes a collapsible ladder with a trigger assembly on top of the ladder. A line is attached to this release arrangement. If the ladder is to be used by the residents of a house with several floors, it must be possible for all residents of all floors to reach this line. As a result, this ladder is not theft-proof. If the line is removed for any reason, the ladder cannot serve as an escape route for multi-story houses if the resident of the top floor is not at home or is unable to fire the ladder in the event of a fire. In addition, this ladder has no device to protect the user from the risk of falling.

US-A-4 243 119 discloses a collapsible ladder but is in no way theft-proof. This ladder is held in position with the help of a hinged hinge. If such a ladder is used by several people at the same time, the hinge located on the top is subjected to a heavy load. The risk of material failure or breakage with respect to the hinge is therefore present, and if this should occur, everyone would address it Head clinging people are in a cases. This ladder also has no safety arrangements to protect the user from falling down.

It is therefore an object of the invention to propose a fire escape that enables a safe escape, is theft-proof and that inconspicuously takes on the house facade.

This object is solved by the features of claim 1.

Advantageous embodiments of the invention are the subject of the dependent claims.

According to the invention, the ladder steps are fastened to the side rails by means of a bolt which provides an articulated connection. These side rails consist of two U-shaped profiles, the flanges of which face each other. Each of these profiles has two flanges that protrude from the bottom of the U-shaped profile on both sides.

The side rail closest to the wall (hereinafter referred to as the inner rail) also has two additional flanges which protrude from the top of the U-shaped profile on both sides and which close when the conductor is folded over the outer rail. The ladder is attached to the wall by means of fastening clips which are adapted to the inner rail. The inner rail is fixed to the fastening clamps using push-through bolts. These push-through bolts also hold the ladder rungs in position. This type of attachment also stabilizes the ladder against lateral movement when it is used.

The rungs consist of a square tube that fits into the two profiles that form the side rails. If the rungs are opened at 90 ° relative to the side rails, the ladder or rungs will be against the walls locked in the side rail profiles. The walls of the rungs are thicker around the bolt holes. When the ladder is folded, the outer rail is held in position by a box-shaped element, the bottom of which is pointing upwards (hereinafter referred to as the closure cap). For this purpose, this box-shaped element is put over the two side rails. To prevent the closure cap from being tipped down with any object from below, it is secured with a locking plug with a spherical handle, which is inserted through a hole in the cap and the outer rail. As a further security measure against the removal of this locking plug by unauthorized persons from below, it is designed so that a certain force is required to be able to remove it.

If the ladder is to be used from the uppermost point, the locking plug and then the closure cap are removed, whereupon the ladder opens by its own weight.

If the occupants of several floors of a building, e.g. In a hotel or apartment block, if one and the same ladder is to be used as an escape route, separate triggering points are installed at each escape station, from which the ladder can be released straight down to the floor. For such conditions, the ladder is assembled as follows:

Corresponding pieces are selected from a standard range of different conductor lengths to give the required total length. (The conductor lengths are connected to one another at the construction site by means of connecting clips, which are not described in detail, in order to form a continuous conductor). The outer rail is at each escape station cut and then inserted a release pin above the cut in the outer rail and held in place by rivets. A hole is drilled in the outer rail below the cut, which is aligned with the hole in the release pin.

A locking plug is inserted through the hole in the outer rail and in the release pin, whereby the rail is reconnected.

In the event of an escape situation, the residents of any floor, regardless of the residents of the upper or lower floors, are able to open the ladder from their escape station and climb down to the ground. The principle is therefore that whoever is the first to open the ladder from the escape station releases it down to the ground from his escape station.

Every time a new escape station is opened on the floors above, the ladder section connects to the ladder already open below.

The release pin, the end of which is slightly tapered for guiding the outer rail during the connection process, also has a collar that replaces the material that was removed from the saw during the cutting process.

The seat belt is adjustable and is tied around the waist. An adjustable buckle is attached to the belt, which in turn is fixed to a locking or blocking arm. The blocking arm is designed so that it fits the outer rail with a sufficient tolerance so that the blocking arm can easily slide down the rail. If the blocking arm exposed to the weight of a person, this is clamped due to the torque acting on the side rail.

If a person wants the ladder from an escape station, e.g. from a window, the seat belt is first tied around the waist. The blocking arm is then inserted into the groove provided in the outer rail. This process is carried out before the refugee climbs out onto the ladder.

If the ladder is entered from the highest escape station, the blocking arm is inserted from the top of the side rail.

If the ladder is entered after it has been released from a floor above, the blocking arm is inserted through a punched-out slot (insertion slot) in the flange of the outer rail. This slot corresponds to the size of the blocking arm for this escape station. The blocking arms have different widths. The blocking arm provided for the top floor is the widest, whereas the subsequent blocking arms, which are provided at each escape station, continue to narrow. Color coding, numbers or the like ensures that the appropriate seat belts are always available on a particular floor.

If an unconscious or physically disabled person has to be led down the ladder, this is made possible by fastening this person to a seat belt whose blocking arm is equipped with a control lever. After this person has been lifted out and secured to the ladder with the help of the seat belt, an assistant enters the ladder from the opposite side and releases the blocking arm with the help of the control lever. By releasing and Tightening the control lever (like a cheek lifter) lowers the person along the side rail at a controlled speed.

• 1. Keine Begrenzung für die Anzahl der Stockwerke, für die die Leiter gleichzeitig dienen soll.
• 2. Sicherheit gegen ein unerlaubtes Betreten des Hauses, da die Leiter nur von der Oberseite oder den anderen Stockwerken, jedoch nicht vom Boden aus freigegeben bzw. ausgeklinkt werden kann.
• 3. Die Bewohner jedes Stockwerkes können die Leiter von ihren entsprechenden Fluchtstationen aus aufklappen lassen, so daß diese gerade nach unten auf den Boden reicht.
• 4. Der Benutzer der Leiter ist durch einen mit einem Blockierarm ausgestatteten Sicherheitsgurt gegen ein Hinabfallen von der Leiter gesichert.
• 5. Das Gefühl einer größeren Sicherheit, wenn man die Leiter von einer Fluchtstation hoch über dem Boden betritt.
• 6. Bewußtlose und körperbehinderte Personen können an der Seitenschiene der Leiter mittels eines Sicherheitsgurtes hinabgeführt werden, dessen Blockierarm einen Steuerhebel aufweist.
• 7. Ein ruhiger und sicherer Abstieg ist durch Wandbefesti­gungsschellen möglich, die die Leiter gegen eine seitliche Bewegung stabilisieren.

In short, the following advantages can be achieved with the aid of the invention.

• 1. No limit to the number of floors for which the ladder should serve at the same time.
• 2. Security against unauthorized entry into the house, since the ladder can only be released or unlatched from the top or the other floors, but not from the floor.
• 3. The residents of each floor can have the ladder opened from their corresponding escape stations so that it extends straight down to the floor.
• 4. The user of the ladder is secured against falling off the ladder by a safety belt equipped with a blocking arm.
• 5. The feeling of greater security when you enter the ladder from an escape station high above the ground.
• 6. Unconscious and physically disabled people can be led down the side rail of the ladder by means of a seat belt, the blocking arm of which has a control lever.
• 7. A quiet and safe descent is possible with wall mounting clamps that stabilize the ladder against lateral movement.

• Fig.1 die zusammenklappbare Leiter in drei verschiedenen Stadien;
• Fig.2 die Leiter in geöffnetem und benutztem Zustand;
• Fig.3 die Art und Weise der Einführung des Blockierarmes des Sicherheitsgurtes in die Leiter bei der obersten Fluchtstation;
• Fig.4 das Einführen des Blockierarmes in die Leiter von einer in der Mitte liegenden Fluchtstation;
• Fig.5 eine Befestigungsart mit der die Seitenschiene an der Wand befestigt und die Sprossen angelenkt werden;
• Fig.6 die unterschiedlichen Breiten der Einführschlitze bei verschiedenen Fluchtstationen;
• Fig.7 die über die Schienen gestülpte Verschlußkappe;
• Fig.8 eine Sprosse in geöffneter Stellung;
• Fig.9 eine Sprosse im Querschnitt;
• Fig.10 die Orientierung der Wandbefestigungsschelle bezüglich der inneren Schiene;
• Fig 11 die Ausrichtung der äußeren Schiene bezüglich der Befestigungsschelle;
• Fig.12 ein Blockierarm mit einem Steuerhebel und
• Fig.13 die Verwendung des Steuerhebels analog eines Wagenhebers.

The invention is explained in more detail below with reference to the drawings. Show it:

• Fig.1 the collapsible ladder in three different stages;
• Fig.2 the ladder in the open and used state;
• 3 shows the way of introducing the blocking arm of the seat belt into the ladder at the top escape station;
• 4 shows the insertion of the blocking arm into the ladder from an escape station located in the middle;
• 5 shows a type of attachment with which the side rail is attached to the wall and the rungs are articulated;
• 6 shows the different widths of the insertion slots at different escape stations;
• 7 the closure cap placed over the rails;
• 8 a rung in the open position;
• 9 shows a rung in cross section;
• 10 shows the orientation of the wall fastening clamp with respect to the inner rail;
• 11 shows the alignment of the outer rail with respect to the fastening clamp;
• Fig.12 a blocking arm with a control lever and
• Fig.13 the use of the control lever analog one Jack.

• Fig.1 zeigt die Leiter bei deren Verwendung, wobei das Bezugszeichen Y die Leiter im geschlossenen Zustand, das Bezugszeichen Z die Leiter in einem halbgeöffneten Zustand, wobei das Öffnen mittels einer Freigabeeinrichtung an einer Fluchtstation erfolgt, und das Bezugszeichen Ø die Leiter im ganz geöffneten Zustand und in Benutzung mit einem Sicherheitsgurt zeigt.
• Fig.2 zeigt, wie bei der Benutzung des Sicherheitsgurtes E mit der Schnalle F der Blockierarm B auf der äußeren Schiene bei einem Sturz festgeklemmt wird.
• Fig.3 zeigt, wie der Blockierarm B in einen Schlitz in die äußere Schiene A eingesetzt wird, und zwar von dem oberen Ende der Leiterschiene aus oder von der Leiterschiene aus, die von der höchstgelegenen Fluchtstation freigegeben wurde.
• Fig.4 zeigt, wie der Blockierarm B des Sicherheitsgurtes E über einen an der Leiterschiene vorgesehenen Einführschlitz G eingesetzt wird, nachdem die Leiter von einem darüber liegenden Stockwerk geöffnet wurde.
• Fig.5 zeigt die Leiter bei einer Fluchtstation unter dem obersten Stockwerk, wobei das Bezugszeichen L die Freigabe­stelle bei geschlossener Leiter, das Bezugszeichen N die von der Freigabestelle aus halbgeöffnete Leiter und das Bezugs­zeichen N die Leiter im ganz geöffneten Zustand an der Freigabestelle zeigt.

The individual drawings show further details.

• 1 shows the ladder in use, the reference symbol Y the ladder in the closed state, the reference symbol Z the ladder in a half-open state, the opening being effected by means of a release device at an escape station, and the reference symbol Ø the ladder in the fully open state Condition and in use with a seat belt shows.
• Fig. 2 shows how when using the safety belt E with the buckle F the blocking arm B is clamped on the outer rail in the event of a fall.
• Fig. 3 shows how the blocking arm B is inserted into a slot in the outer rail A, namely from the upper end of the conductor rail or from the conductor rail that has been released from the highest escape station.
• 4 shows how the blocking arm B of the seat belt E is inserted via an insertion slot G provided on the conductor rail after the conductor has been opened from a floor above it.
• 5 shows the ladder at an escape station under the top floor, the reference symbol L indicating the release point when the conductor is closed, the reference symbol N indicating the half-open conductor from the release point and the reference symbol N indicating the conductor in the fully open state at the release point.

The sketch marked with the reference symbol M shows the release pin 0, which is attached to the outer rail A. The detailed drawing shown in the circle illustrates make this clearer. From this drawing it can be seen that the end of the release pin 0 is tapered in order to facilitate the insertion of the outer rail A underneath. The same detailed drawing shows that the release pin 0 has a collar R which replaces the material which was lost when the outer rail A was sawn through.

• Fig.6 verdeutlicht anhand der Bezugszeichen G-I und G-II die verschiedenen Breiten der Einführschlitze G an der oberen und unteren Fluchtstation, wodurch der Blockierarm B nicht durch den Schlitz G herausfallen kann, während dieser die Leiter hinabgleitet.
• Fig.7 verdeutlicht, wie die Leiter mittels einer Verschluß­kappe G und eines Verriegelungsstöpsels K diebstahlsicherer gemacht wird.
• Die Fig.8 verdeutlicht, wie die Sprosse den Aufklappvorgang beendet, falls dieser eine Stellung von 90° bezüglich den Schienen A und S aufweist. Die Enden der Sprossen sind an der Stelle X bis zur Mittellinie des Bolzenloches schräg abgeschnitten.
• Fig.9 stellt einen Querschnitt der Sprosse W dar, wobei die Wände um die Bolzenlöcher herum dicker bzw. verstärkt sind (siehe Bezugszeichen U).
• Fig.10 zeigt, wie die Wandbefestigungsschelle P und die innere Schiene S zueinander ausgerichtet sind. An den beiden Schenkeln der inneren Schiene S sind Flansche T ausgebildet, die sich bei zusammengeklappter Leiter über die äußere Schiene A erstrecken.
• Fig.11 zeigt die äußere Schiene A und den Blockierarm B im Schnitt. An dem Blockierarm B ist ein Befestigungspunkt C für die einstellbare Schnalle F des Sicherheitsgurtes E vorgesehen. Die äußere Schiene A weist am Bodenteil Vor­sprünge H auf, die mit einer gewissen Toleranz in Nuten E des Blockierarms B passen. Aus der Figur 11 ist die Ausrich­tung der äußeren Schiene A bezüglich des Blockierarmes B ebenso ersichtlich.
• Fig.12 zeigt die Vorder- und Rückseite des mit einem Steuerhebel V versehenen Blockierarmes B.
• Fig.13 zeigt, wie man den Steuerhebel V in Art eines Wagenhebers zum Hinablassen einer bewußtlosen Person im Sicherheitsgurt E benutzen kann.

Wall mounting clips P are provided on the steps above and below the release stations, which stabilize the ladder against lateral movement.

• Fig. 6 illustrates with reference numerals GI and G-II the different widths of the insertion slots G at the upper and lower escape stations, whereby the blocking arm B cannot fall out through the slot G while it slides down the ladder.
• Fig. 7 illustrates how the ladder is made more secure against theft by means of a closure cap G and a locking plug K.
• Figure 8 illustrates how the rung ends the opening process if it has a position of 90 ° with respect to the rails A and S. The ends of the rungs are cut diagonally at point X up to the center line of the bolt hole.
• 9 shows a cross section of the rung W, the walls around the bolt holes being thicker or reinforced (see reference symbol U).
• 10 shows how the wall fastening clamp P and the inner rail S are aligned with one another. Flanges T are formed on the two legs of the inner rail S and extend over the outer rail A when the conductor is folded.
• Fig. 11 shows the outer rail A and the blocking arm B in section. A fastening point C for the adjustable buckle F of the seat belt E is provided on the blocking arm B. The outer rail A has projections H on the bottom part which fit into the grooves E of the blocking arm B with a certain tolerance. The alignment of the outer rail A with respect to the blocking arm B can also be seen from FIG.
• 12 shows the front and rear of the blocking arm B provided with a control lever V.
• Fig. 13 shows how you can use the control lever V in the manner of a jack to lower an unconscious person in the seat belt E.

The fire escape consists of U-shaped metal profiles as side rails, the ends of the rungs W being accommodated in the interior of the U-shaped profiles and fastened to the flanges of the U-shaped profiles by means of bolts. The outer rail A, as one of the side rails, is articulated to the inner rail S by means of the rungs, the profiles for the inner rails S on their outer sides near the bottom of the U-shaped profile having flanges which fit into the wall fastening clamps P, while on the outside of the two exposed leg ends of the U-profile smaller flanges T are provided, which close when the conductor is folded over the outer rail A. The profile for the outer rail A has smaller flanges H on the bottom which fit into the inside of a blocking arm B.

The outer rail A is adapted to the required number of escape stations by sawing it through at the required locations. A release pin 0 is in the Arranged inside the outer rail A above the cut and fastened to the outer rails A with the aid of rivets. A suitably sized collar R provided on the release pin O replaces the material removed by the saw.

Each escape station has a locking plug K which fits into a hole in the outer rail, this hole being aligned with a corresponding hole in the release pin O.

The outer rail A is clamped to the inner rail S by means of a sealing cap J and a locking plug K at the upper end of the ladder.

When used, the ladder is stabilized against lateral movement by fastening clips P. These mounting clamps P are designed so that they fit together with the inner rail S. The fastening clamps P are fastened to the inner rail S by means of the same bolt fastening as that of the rungs W.

The rungs W have parallel oblique cuts at an angle of 45 ° to the center line of the bolt holes X. In this way, the ladder is blocked against further opening movement if the rungs have opened 90 ° with respect to the rails A and S.

The insertion slots G provided for these blocking arms B in the flanges of the outer rail A have a different width at each escape station. The slot at the top is widest, with the width being continuously reduced at each successive escape station, whereby a certain width of the insertion slot G corresponds to a certain escape station, and whereby each blocking arm B via the slots of the one below Escape stations can slide without "derailment".

The blocking arm B has guide grooves E, into which the flanges H of the outer rail A fit, and forms an extension on which a fastening point or a fastening hole C for the adjustable buckle F of the seat belt E is formed.

A load acting on the fastening point C of the buckle F of the seat belt E exerts a torque on the blocking arm B. As a result of the tolerances provided between the flanges H of the outer rail A and the grooves E of the blocking arm B, a clamping or blocking effect in the direction of the load is achieved.

The blocking arm B is equipped with a control lever V if a physically disabled or unconscious person is to be let down in the seat belt E.

The equipment according to the invention, namely a collapsible fire escape and a blocking arm with safety belt and control lever, enables the rescue of a physically handicapped person by an auxiliary person actuating the control lever, which, similar to the action of a jack, clamps and releases the blocking arm B. In this way, the person in the seat belt E can be lowered along the outer rail A at a controlled speed.

Claims (12)

1. Collapsible ladder made of metal, characterized in that the fire escape in the normal state (Y) is folded and theft-proof and that in the event of a fire, the fire escape can be folded apart by a simple manual process at each escape station to form a fire escape (Z), which leads straight down to the floor and has guides for locking arms (B) equipped with seat belts (E). 2. Fire escape according to claim 1, wherein the side rails (S, A) of the ladder consist of U-profiles and the rungs (W) are inserted into the U-profile and fastened to the legs of the U-profile with bolts, and wherein one of the Side rails - the outer rail (A) - is articulated by means of the rungs (W) on the inner rail (S), characterized in that the U-profile of the inner rail (S) on its outer sides near the floor has flanges which fit in wall mounting clamps (P), while on the top of the two legs of the U-profile there are smaller flanges (T) on the outside, which close when the conductor is folded over the 80 outer rail (A) and that the U-profile of the outer rail has smaller flanges (H) on the bottom that fit in a blocking arm (B). 3. Fire escape according to claims 1 and 2, characterized in that the outer rail (A) to the the required number of escape stations is adjusted by sawing them through at the appropriate locations, by arranging a release pin (O) in the outer rail (A) above the cut, which is riveted to the outer rail and by the release pin (O) has a collar (R) that replaces exactly the material that was removed by the sawing process. 4. Fire escape according to claims 1, 2 and 3, characterized in that each escape station is equipped with a locking plug (K) which fits into a hole in the outer rail (A), and that the hole in the outer rail with a corresponding hole in the release pin (O) is aligned. 5. Fire escape according to one of the preceding claims, which is protected against unauthorized use by people from below, characterized in that the outer rail (A) with the aid of a closure cap (J) and a locking plug (K) at the upper end of the ladder on the inner Rail (S) is locked. 6. Fire escape according to one of the preceding claims, characterized in that the ladder is stabilized in use against lateral movement by fastening clips (P) which are adapted to the inner rail (S) and on the ladder by the same bolt fastenings as for the rungs (W) are attached. 7. Fire escape according to one of the preceding claims, characterized in that the rungs (W) have parallel oblique cuts at an angle of 45 ° from the center line of the bolt holes (X). 8. fire escape according to claim 3, characterized in that for the blocking arms (B) insertion slots (G) in the Flanges of the outer rail (A) are provided which have different widths at each escape station, the greatest width being at the top end of the ladder and the width at each successive, underlying escape station becoming sequentially smaller, and in that the blocking arms (B) have different widths for the insertion slots (G) at the specific escape stations, so that each blocking arm (B) can slide over the insertion slots of the underlying escape stations without derailment. 9. Fire escape according to claims 3 and 6, characterized in that the blocking arm (B) sliding grooves (E) which fit to the flanges (H) of the outer rail (A), and a stepped fastening point (C) for fastening an adjustable Has buckle (F) of a seat belt (E). 10. Fire escape according to claim 6, characterized in that the blocking arm (B) exerts a torque on the side rail (A, H), if this is exposed to a load at the fastening point (C) to which the seat belt (E) is attached , this torque causing a locking effect in the direction of the load due to deliberate tolerances between the side rail and the locking arm. 11. Fire escape according to one of claims 1 and 8, characterized in that the blocking arm (B) has a control lever (V) which is used for lowering physically handicapped or unconscious people in the seat belt (E). 12. A method of using the fire escape, the blocking arm and the control lever according to the preceding claims for the rescue of physically disabled and unconscious People, characterized,
that the control lever is operated by an auxiliary person, the control lever being operated like a jack for setting and releasing the blocking arm (B), whereby the person in the seat belt (E) can be lowered along the outer rail (A) at a controlled speed.

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