EP2252756B1 - Gate having an escape door that can be stabilized - Google Patents

Description

The invention relates to a gate with stabilizable escape door, according to the preamble of claim 1.

For big goals, such as For example, for trucks, is often required by regulations of competent supervisory authorities, an escape door, which allows an emergency exit the building in an emergency, even with the gate shut off. The escape door must not have a threshold to the floor, in order to exclude the risk of tripping on the door. As a result, however, the plate of the door is weakened, as it has a downwardly open recess for the escape door. If such a door panel is pivoted to open the door upwards under the ceiling of the room in a horizontal position, it hangs downwards, which is allowed only to a certain extent.

So that this maximum allowable level is not exceeded, either complex, weighty and expensive stiffeners are required or it must be made after closing the escape door stiffening connections between the escape door and the adjacent sections of the door leaf.

The current state of the art describes DE 10 2004 047166 with stabilizers, which are arranged horizontally only on the lower edge of the escape door and are pushed over the locking mechanism of the escape door in guides on the door panel or locked via swivel Krallscheiben with the door plate, so that in the result a tension in the axial direction.

A major limitation of this system is that the stabilizers only via an axial locking with its counterpart of the Torplatte can be connected and therefore always have a game to the base profile, which precludes the actually required stabilization of the door panel.

Against this background, the invention has the task of developing a stabilizer, the escape door and door leaf in the closed state connects together and produces a rigid and play-free connection, while making a low-backlash and smooth movement during opening and closing of the escape door possible.

As a solution, the invention presents a gate with stabilizable escape door with the features specified in claim 1.

The core idea of the invention is thus that during the movement of the opening and closing a game between the stabilizers and their counterparts, the base profiles consists, in the closed Condition, however, pressure plates eliminate this game by being pressed against the inner wall of the base profile.

Characteristic of the use of this inventive system is that when the escape door is open, a first stabilizer is located exclusively in the area of the escape door and a second stabilizer exclusively in the area of the goal plate. In this state, there is no mechanically rigid connection between the door plate and the escape door, so that the escape door is freely pivotable.

If the escape door is closed to close the gate, both stabilizers are released from a possible fixation in the escape door or in the gate plate and each shifted by about half their length, so that they in corresponding counterparts on the adjacent gate plate or on the Door panel intervene. Then the two stabilizers bridge both joints between the escape door and the goal plate. In this position, they are connected without play by means of their pressure plates with the surrounding base profile.

As a variant of the shaping of the pressure plate, the invention proposes an elongated strip. Particularly stable is a U-shaped profile, z. B. made of bent sheet steel. It makes sense that at least one pressure plate of a stabilizer in a recess of the base profile is displaced in the longitudinal direction, so that an unimpeded movement in the longitudinal direction is possible.

At the same time, the pressure plate should be able to be pressed into the recess, in order to be able to transfer as high forces as possible between the stabilizer and the base profile. It is also advantageous if at the same time the recess as centering serves, which excludes unwanted pivoting of the pressure plate about the longitudinal axis of the base profile or stabilizer.

Each stabilizer must be equipped with at least two pressure plates, so that for each applied force and the corresponding counterforce is transferable. These two pressure plates must be pressed apart for backlash-free fixation of the stabilizer and pressed against the inner wall of the surrounding base profile.

If the base profile z. B. is square and two pressure plates are arranged therein, whose cross-section is considerably smaller, but also square and the longitudinal side of the pressure plates slightly shorter than the broad side of the rectangular base profile, then both rectangular pressure plates are always centered in the larger and also rectangular base profile.

To push away both pressure plates from each other, z. B. at least one cam, which can be pivoted about a parallel to the pressure surface of the pressure plates aligned axis. This pivot axis can be aligned both transversely to the longitudinal axis of the base profile and parallel to the longitudinal axis or at a different angle.

If several cams are present, it makes sense to align their axes of rotation all parallel to the longitudinal axis of the base profile, because then all the cams can be pivoted together via a single axis connecting them.

If all the cams are pivotable transversely to the longitudinal axis, their common movement is possible via a respective hinged lever which is parallel to the longitudinal axis.

An alternative to a cam is a pressure wheel, which has a cam on its circumference for each pressure plate.

The cams are created by a constantly growing diameter in a certain angular range. This angular range is z. B. two pressure plates per stabilizer less than 180 °, with three, evenly distributed over the circumference pressure plates less than 120 ° and four, uniformly over the circumference arranged pressure plates only less than 90 °.

In the basic form, the radius of the pressure wheel increases in the region of the smallest diameter cam, in which the pressure plates have a clearance relative to the inner wall, to the largest diameter, in which the pressure plates are pressed firmly against the inner wall of the base profile. If either the cam itself or at least one member in the power transmission for adjusting the cam has a certain elasticity, as a sub-variant of the radius can be reduced again after reaching the maximum value, whereby the cam engages in this position. It is advantageous that he then does not jump out of his rest position by slight shocks. It should be noted that the force required to overcome the detent must be provided and all members of the transmission must be sufficiently rigid dimensioned to transmit this force can.

A very advantageous number of pressure plates per stabilizer are two, provided that their direction of movement between the pressure position and the play-afflicted position is aligned perpendicular to the goal plate, and the base profiles are fixed so stable on the goal plate and on the escape door, that they are practically not on their surface can move.

In particular, if the base profile can be compared to the door panel or the escape door by elasticities and / or by play in the attachment move or pivot, a higher number of pressure plates is possible and useful.

A stabilizer already works with a single cam or a single pressure wheel, if the pressure plates are designed to be so stiff along their length that even at the ends of a minimum contact pressure is achieved.

However, if the pressure plates z. B. have a very narrow profile or other reasons can not be performed very rigid, the number of cams and the print wheels can be increased so that over the entire length of the pressure plate away a uniform pressure force can be achieved. A sensible combination for a stabilizer are two pressure plates with two pressure wheels.

In order to take the pressure plates in the longitudinal displacement of the stabilizer, so to fix in their longitudinal position relative to the stabilizer, can be attached to each pressure plate for each pressure wheel each have a pair of facing them drivers, which are respectively arranged on both sides of the pressure wheel, wherein the Distance between the two drivers is slightly larger than the Strength of the pressure wheel at this point. When moving the stabilizer and the pressure plate is pushed by the pressure wheel by the driver, in the axial direction. Through the game of the driver pair opposite the pressure wheel, the pressure wheel can pivot relative to the pressure plates. As a result, the cam is effective, which moves the pressure plate in the radial direction outwards and thereby presses against the inner wall of the base profiles.

An advantageous embodiment is the connection of all pressure wheels by a support tube which transmits the torque for pivoting the pressure wheels when pressing the pressure plates and at the same time leads the pressure wheels themselves mechanically. As a result, all printing wheels are moved and pivoted together and at the same time.

For the linear movement as well as for the pivoting of the supporting tube together with all pressure wheels arranged thereon, a rotatably mounted threaded spindle is suitable as an advantageous variant, which runs through at least one nut within the support tube. When the threaded spindle is twisted and the nuts are secured against rotation in the support tube, the nut translates the rotational movement of the threaded spindle into the linear movement of the support tube. So that the pressure wheels do not pivot on the largest part of the displacement path from the stabilizer, the invention proposes that at least one, outwardly projecting guide pin is fixed on the support tube, which engages in a guide groove in the inner wall of the base profile parallel to its longitudinal axis runs. Guide pin and guide bring the counterforce, which is held against the torque of the threaded spindle.

Only at the end of the displacement is a pivoting of the pressure wheel for clamping the pressure plate is desired. For this, the guide groove merges at the end of the displacement area into a curve which extends on the surface of a cylinder whose radius corresponds to the length of the guide pin, wherein the guide groove always aligned in the region of the curve at an angle of less than 90 ° to the longitudinal axis of the stabilizer is. As a result, the pressure wheel pivots about an angle which is predetermined by the deviation of the curved portion of the guide groove relative to the straight part. This pivoting is transmitted via the support tube on all other pressure wheels, so that the stabilizer presses properly on each pressure wheel to the inner wall of the base profile.

For a larger number of pressure plates per stabilizer, in particular for four or more pressure plates, the invention proposes that the control of the pivoting movement of the pressure wheels for pressing the pressure plates out of the stabilizer out in an adjoining area. For this purpose, the threaded spindle is extended beyond the stabilizer and connected via two sequentially interconnected switching sleeves with a rotating drive, wherein at least one transverse to the longitudinal axis aligned guide arm serves as a connection between the switching sleeves, which in a partially curved backdrop on the respective associated shift sleeve slidably is. The advantage of this arrangement is that thus the pivot angle for pressing the pressure plates is independent of their number, so even with a very large number of pressure plates can still be very high.

In both cases, the threaded spindle requires a rotating drive, such. B. an electric motor.

Another useful variant is the connection of a stabilizer with a second stabilizer via a clutch. This clutch is automatically engageable and disengageable in a sub-variant by switching lugs on the displacement of the stabilizers. Then a stabilizer can push its neighbor in one direction of movement and pull in the other direction of movement.

In a further, very interesting variant, the invention proposes slightly angled pressure plates, which thereby produce a small angle between the door plate and the adjacent escape door when pressing, when the break point of the respective pressure plate is positioned exactly in the joint. As a result, a shaping of the door plate is achieved together with the escape door, which counteract the sagging of the door in a horizontal position. To do this, two pressure plates arranged in a stabilizer opposite one another must at least partially retract a pressure plate at an angle into the interior of the stabilizer, and the opposing pressure plate must be angled outwards at the same angle. As a result, in the closed state of the door, the area near the escape door is pushed out of the plane by a small amount. When the gate is pivoted to a horizontal position, gravity within the limits of the resilience of the gate plate pushes this area closer to the plane, thereby reducing the amount that the gate sags downwards.

In this arrangement, it should be noted that to achieve a backlash, the pressure plates to a greater amount of the Inner wall of the base profiles must be withdrawn, as it is required for fully aligned pressure plates.

As a differently structured embodiment, the invention proposes that when the escape door is open there are two stabilizers on it. These two stabilizers can either be arranged one behind the other in a continuous base profile or two base profiles are mounted one above the other on the escape door. In the latter case, the corresponding counterparts on the goal plate must also be mounted at different heights.

For both embodiments, it is conceivable that the two stabilizers via pull and push rods, which are connected to each other via lever, are connected to the closing lever of the escape door and moved together with the Verschließhebel. Then it must be ensured at the end of the displacement path of both stabilizers that the pressure plates are pressed against the inner wall of the base profile. For z. B. the aforementioned cams are used, which are pivotable transversely to the displacement of the stabilizers.

For multi-cam stabilizers, all cams should be connected by a pull-push bar aligned parallel to the travel. It is conceivable to use this pull-push rod e.g. To connect via train-push lever with the Schlieamechanismus the escape door and thereby move with.

When the pull-push rod with the cams articulated thereon has reached the end of its displacement, it is conceivable that the outermost cams will encounter a stop which, upon further advancement of the pull-push rod, will cause the cam to pivot and thus ensures the application of a contact pressure on the pressure plates.

Alternatively, a movement of the cam via pneumatic cylinders, hydraulic cylinders or by means of electrical drives is conceivable.

To actuate these cylinders, a hydraulic line or a tube filled with air can lead to another cylinder, which is actuated by the closing lever of the escape door.

In order to provide a sufficient operating force for the entire mechanism of the stabilizers, the closing lever could be extended beyond that usual for doors, as e.g. is common for doors on ships or in front of safes.

But also in this embodiment, the locking lever should automatically pivot when interrupting the operation in a defined position, so that an uncoordinated assignment of the state of all elements is avoided.

• Figur 1 a: Torplatte mit geschlossener Fluchttür
• Figur 1b: Torplatte mit geöffneter Fluchttür
• Figur 2: Sockelprofil mit Stabilisator

In the following, further details and features of the invention will be explained in more detail by way of examples. However, these are not intended to limit the invention, but only to explain. It shows in a schematic representation:

• FIG. 1 a: Gate plate with closed escape door
• FIG. 1b : Gate plate with opened escape door
• FIG. 2 : Base profile with stabilizer

• In Figur 1a ist perspektivisch eine Torplatte 1 dargestellt. In der großen Torplatte 1 ist eine kleine Fluchttür 2 schwellenfrei eingelassen, weshalb die Öffnung für die Fluchttür 2 die Form einer Einbuchtung 11 im Bereich der Unterkante 12 der Torplatte 1 hat.

The figures show in detail:

• In FIG. 1a In perspective, a gate plate 1 is shown. In the large door panel 1, a small escape door 2 is inserted without a threshold, which is why the opening for the escape door 2 has the shape of a recess 11 in the region of the lower edge 12 of the door panel 1.

At the lower door edge 12 of the door and on the lower door edge 21 of the escape door 2 each base profiles 13 are attached. In the illustrated embodiment, the base profile 13 is formed cylindrically in the door plate 1 and the escape door 2 and has four grooves in its interior. In the area of the joints between the escape door 2 and door panel 1, a stabilizer 3 is shown in dashed lines, which protrudes into the base profile 13 on the escape door 2 to one half and with the other half in the base profile 13 in the lower edge of the door 12.

In FIG. 1 a is not shown that the stabilizers 3 are slightly loosened before opening the escape door within the base profile 13 so that they are displaced with a game within the base profile 13.

Very good to understand, however, is in FIG. 1a in that the two stabilizers 3 in the illustrated state with the escape door 2 closed, when they are spread apart within the three base profiles 23, stabilize the lower edge 12 of the goal plate 1. Then, the door panel 1 can be pivoted as a whole, as if it were a one-piece, stable plate, which is not weakened by the recess 11. It is irrelevant whether the door panel 1 as a pivot around a vertical pivot axis or a horizontal Is moved pivot axis, or whether the door panel 1 is moved as a rigid element by means of rails from the vertical position to a horizontal position under the ceiling or whether the door panel 1 is formed by division into a plurality of hingedly interconnected strips as a sectional door that in a rail guide is moved either under the ceiling or on a side wall.

In FIG. 1b is the same door plate 1 as in FIG. 1a drawn, but here with the escape door open 2. When the escape door is opened; the fixed base profile 13 is pivoted with, so has moved relative to the door plate 2. Of course, this movement is only possible if the two adjacent base profiles 13 are no longer interconnected by the stabilizer 3, which previously also bridged the joint between them. Instead, one of the two stabilizers 3 has to be removed from the joint area. In FIG. 1b is a stabilizer 3 completely inserted into the base profile 13 of the escape door 2 and does not interfere with the opening in this state. Meanwhile, the other stabilizer 3 has moved out of the escape door 2 and is only in the base profile 13 in the area of the lower door edge 12. In this position, the escape door 2 is thus freely pivoted. FIG. 1b thus shows the position of the two stabilizers 3 with the escape door 2 open.

The stabilizers 3 are in the FIGS. 1 a and 1b shown only schematically with their outline as a dashed line. The more detailed structure of the stabilizers 3 shows.

FIG. 2 : Here is shown as an oblique view of the base profile 13 on the lower door edge 12 of the door panel 1 in section, from which a stabilizer 3 protrudes to a part.

As an exemplary embodiment of the base profile 13, a double-walled, circular hollow profile is presented, in whose inner wall four grooves are eirzgebracht. Of these, the upper groove and the lower groove are used as the guide groove 16. Dahinein engages a guide pin 43, in the illustrated embodiment with a wheel at its end, which rolls on the inner surfaces of the guide groove 16.

Of the two guide pins 43 of this embodiment, the upper is completely visible because it protrudes from the end of the illustrated part of the base profile 13. The lower guide pin 43 is partially concealed at its end by the left pressure plate 31.

In FIG. 2 two pieces of pressure plates 31 can be seen as part of the stabilizer 3. These two pressure plates 31 have a U-shaped profile, wherein the surface which connects the two legs of this profile with each other, serves as a pressure plate which can be pressed within the groove to the inner wall 15 of the surrounding base profile 13. The force required for this is transmitted by the pressure wheel 4, which is shaped as a cylindrical disc and carries two cams 41 on its cylinder jacket surface. In the example shown, these cams 41 are formed as a wedge-shaped rising ramp, which carry on its highest part a notch into which a cylindrical counterpart engages, which is fixed in the U-shaped pressure plate 31.

In FIG. 2 is understandable that at a longitudinal rotation of the print wheel 4 from the position shown, the two cams 41 with their highest part press the pressure plates 31 apart. Then they press themselves within the two grooves of the base profile 13 to the inner wall 15, whereby the stabilizer 3 is firmly clamped within the base profile 13.

In FIG. 2 is the lead screw 5 can be seen, which protrudes with a short distance from the print wheel 4. The counterpart to the threaded spindle 5, the nut is integrated in this embodiment in the print wheel 4.

In FIG. 2 It is easy to emulate how the threaded spindle 5 first provides for the longitudinal displacement of the stabilizer 3 in the direction of the longitudinal axis 14 of the base profile 13: For this, the support tube 42 is firmly connected to the pressure wheel 4, in which the threaded spindle 5 is located. When the threaded spindle 5 is rotated, the pressure wheel 4 is prevented from following this rotation, because it is prevented by the support tube 42 and the two guide pins 43, since the guide pin 43 limited by the guide groove 16 in the illustrated area of the base profile 13 only allow a longitudinal movement. By rotating the threaded spindle 5 so the stabilizer 3 moves in the longitudinal axis 14 of the base profile thirteenth

In FIG. 2 not shown, but easy to understand, as at the end of the travel required for the bracing of the two pressure plates 31 pivotal movement of the print wheel 4 is performed. For this purpose, the guide groove 16 of the base profile 13 in a curved area over. The in FIG. 2 Upwardly facing guide pin 43 is forced into a - not shown - curve of the guide groove 16 and thereby moves towards the left edge of the image. The lower guide pin 43 will also pivot through a - not shown - curve of the guide groove 16 in the direction of the right edge of the image, whereby the required Pivoting movement of the pressure wheel 4 is initiated. This pivotal movement must be completed when the two notches on the highest point of the cam 41 in the region of the cylindrical pressure elements of the pressure plates 31.

In FIG. 2 the displacement of the stabilizer 3 in the direction of the longitudinal axis 14 of the base profile 13 is characterized by a double arrow on the support tube 42. The pivoting movement of the pressure wheel 4 for bracing the two pressure plates 31 describes a curved double arrow on the end face of the pressure wheel 4th

LIST OF REFERENCE NUMBERS

1

A door panel

11

Indentation in the region of the lower edge 12 of the door plate 1

12

Bottom edge of door plate 1

13

Base profiles in the area of lower door edge 12 and lower door edge 21

14

Longitudinal axis of the base profiles 13

15

Inner wall of the base profiles 13

16

Guide groove in the base profile 13 for receiving the guide pin 43rd

2

escape door

21

Door lower edge of the escape door 2

3

Stabilizer, in base profile 13

31

Pressure plate, part of the stabilizer 3

4

Print wheel for pressing the pressure plates 31

41

Cam on pressure wheel 4

42

Support tube for connecting pressure wheels 4

43

Guide pin engages in the guide groove 16 of the base profile 13 a

5

Threaded spindle for the displacement of the stabilizer 3

Claims (20)

1. Gate comprising a stabilizable escape door, comprising

   - a gate plate 1 and

   - an escape door 2, which is mounted, so as to be pivotable, in a recess 11, which originates from the gate lower edge 12 of the gate plate 1, and

   - at least three base profiles 13,

   - which are coaxial at least in pairs and

   - of which at least two are disposed on both sides of the recess 11 in the region of the gate lower edge 12 and

   - of which at least one is fastened in the region of the lower edge 13 of the escape door 2, and

   - at least two elongated stabilizers 3, which are displaceable within the base profiles 13, along the longitudinal axis 14 thereof, wherein

   - the stabilizers 3 have play with respect to the inner wall 15 of the base profile 13 that surrounds them and

   - on each stabilizer 3 at least two pressure plates 31 are disposed, characterised in that, with the escape door 2 open, a first stabilizer 3 can be positioned exclusively in the region of the escape door 2 and a second stabilizer 3 can be positioned exclusively in the region of the gate plate 1, and, with the escape door 2 closed and with the fixing released, the stabilizers 3 can be displaced in the escape door 2 and/or in the gate plate 1 to a position at which the two stabilizers 3 bridge both joints between the escape door 2 and gate plate 1 and the pressure plates 31 can be connected play-free with the surrounding base profile 13.
2. Gate according to the preceding claim 1, characterised in that at least one pressure plate 31 is formed as an elongated strip.
3. Gate according to the preceding claim 2, characterised in that the strip has a U-shaped profile.
4. Gate according to one of the preceding claims, characterised in that that at least one pressure plate 31 can be displaced within a recess 16 of the base profile and can be pressed into the recess 16.
5. Gate according to one of the preceding claims, characterised in that, by means of at least one cam 41, at least two pressure plates 31 can be pushed away from one another and against the inner wall 15.
6. Gate according to one of the preceding claims, characterised in that that at least two pressure plates 31 can be pressed by means of at least one pressure wheel 4 having a cam 41 in each case for each pressure plate 31.
7. Gate according to the preceding claim 6, characterised in that, on the pressure plates 31, for each pressure wheel 4, two carriers 31 are fastened, which are arranged in each case opposite one side of the pressure wheel 4, the distance between the carriers being slightly larger than the thickness of the pressure wheel 4 at this point.
8. Gate according to one of the preceding claims, characterised in that that at least one stabilizer 3 is equipped with two pressure plates 31 and two pressure wheels 4.
9. Gate according to one of the preceding claims, characterised in that at least two pressure wheels 4 are connected together by means of a carrier tube 42.
10. Gate according to one of the preceding claims, characterised in that
    all pressure wheels 4 of a stabilizer 3 are pivotable about its longitudinal axis..
11. Gate according to one of the preceding claims, characterised in that

    - in the carrier tube 42, at least one nut is arranged, through which a rotably mounted threaded spindle 5 passes and

    - on the carrier tube 42, at least one outwardly projecting guide bolt 43 is fastened, which engages in a guide groove 16, which runs in the inner wall of the base profile 13 parallel to the longitudinal axis 14 thereof,

    - wherein the guide groove 16, at the end, merges into a curve, which runs on the surface of a cylinder, the radius of which corresponds to the length of the guide bolt 43 and

    - the guide groove 16, in the region of the curve, is always oriented at an angle of less than 90 degrees with respect to the longitudinal axis of the stabilizer.
12. Gate according to one of the preceding claims, characterised in that the threaded spindle 5 is extended beyond the stabilizer 3 and is connected, via two sequentially interlinked shift sleeves, to a rotating drive, wherein, as a connection between shift sleeves, there serves at least one guide arm, which is oriented transversely to the longitudinal axis and is displaceable within a partially curved gate on the associated shift sleeve.
13. Gate according to one of the preceding claims, characterised in that the threaded spindle 5 is moveable by means of rotating drive, for example an electric motor.
14. Gate according to one of the preceding claims, characterised in that that a stabilizer 3 can be connected to a second stabilizer 3 by means of a coupling.
15. Gate according to the preceding claim 13, characterised in that the coupling can be automatically engaged and disengaged by means of shift lugs on the displacement path of the stabilizers 3.
16. Gate according to one of the preceding claims, characterised in that, of two pressure plates 31 that are arranged opposite one another in a stabilizer 3, one pressure plate 31 is drawn at least partly at an angle into the interior of the stabilizer 3, and the opposite pressure plate 31 is angled with the same angle, so as to face outwards.
17. Method for using a gate according to one of the preceding claims, characterised in that

    - with the escape door 2 open, a first stabilizer 3 is positioned exclusively in the region of the escape door 2 and a second stabilizer 3 is located exclusively in the region of the gate plate 1, and

    - for closing the gate

    - in the first step, the escape door 2 is closed and

    - in the second step, pressure is no longer exerted on pressure plates 31 of the two stabilizers 3 and

    - in the third step, both stabilizers 3 are pushed by about half their length in each case until both stabilizers 3 are located with one half in the gate leaf 1 and with the other half in the escape door 2, and

    - in the fourth step, pressure is exerted again on the pressure plates 31 and the gate is opened together with the escape door 2 fixed therein and

    - for opening the gate, the aforementioned steps take place in reverse sequence.
18. Method for using a gate according to one of the preceding claims 5 and 17, characterised in that

    - in the second step, the cams 41 of the two stabilizers 3 no longer exert pressure on the pressure plates 31 and

    - in the fourth step, all cams 41 again exert pressure on the pressure plates 31 and the gate is opened together with the escape door 2 which is stably fixed therein.
19. Method for using a gate according to the preceding claims 17 or 18, characterised in that, in the third step of gate closure, the first stabilizer 3 is coupled to the second stabilizer 3 and displaces the latter too, and in the corresponding gate-opening step, draws it back again.
20. Method for using a gate according to the preceding claims 16 and 17, characterised in that in the fourth step of gate closure, the pressure plates 31, which are angularly shaped, are located with their first leg in the gate plate and with the other, second leg, which is angled with respect to the first leg, in the escape door 2, and in the fourth step, by means of the pressure of the cams 41 and within the scope of elasticity of the gate plate 1 and the escape door 2, an angle in each case forms between the left portion of the gate plate 1 and the escape door 2 and the right portion of the gate plate 1.

Images