Ladder locking

Abstract

The invention relates to a device for regulated access to an upper protected area, comprising a ladder (1) extending between a lower area from which a user can freely access and said upper protected area, and a means for prohibiting or preventing the use of at least some of the rungs (4) of this ladder, this means comprising a panel (5) and means for connecting it to the ladder which maintain the panel, in a first state, applied against the rear (B) of the rungs (4) of the ladder relative to its access face (A) and in a second state remote from these rungs (4), characterized in that the aforementioned connecting means (6) have at least one limited degree of freedom, in translation parallel to the longitudinal direction of the ladder (1) and which is exerted after the end of the movement of the panel when it passes from its second state to the first and before the start of the reverse movement.

Description

[0001] The present invention relates to the blocking of accesses, in particular those using a ladder having an access face, whether inclined or even vertical. BACKGROUND OF THE INVENTION

[0002] It is known from the state of the art to prevent access to a ladder by masking some of the rungs of this ladder by means of a panel covering its access face, which only an authorized user is able to remove. As an example, we will cite the condemnations which are described in the standard NF E 85-012 of December 2011.

[0003] There are also ladders that are sufficiently far from the structures to which they are attached so that an unscrupulous user can access their rungs from one side or the other of the ladder. This is particularly the case with inclined ladders. In this case, access locking devices are known that are operated on the side of the ladder opposite the access side. Such a device is illustrated by document DE-20 2011 102506.

[0004] The function of this panel is to make some of the rungs of the ladder unusable, at least for correct support, so that, for the user, generally wearing work shoes (and not climbing shoes), it is not possible to place his foot on a rung (and even to grip it correctly) when the panel is pressed against the ladder opposite its access face.

[0005] The present invention intends to propose a device for controlling and prohibiting access of this latter type. SUBJECT OF THE INVENTION

[0006] To this end, the invention relates to a device for regulated access to an upper protected area, comprising a ladder extending between a lower area from which a user can freely access and said upper protected area, and a means for prohibiting or preventing the use of at least some of the rungs of this ladder, this means comprising a panel and means for connecting it to the ladder which maintain the panel, in a first state, applied against the rear of the rungs of the ladder relative to its access face and in a second state remote from these rungs. The aforementioned connecting means have at least one limited degree of freedom, in translation parallel to the longitudinal direction of the ladder and which is exerted after the end of the movement of the panel when it passes from its second state to the first and before the start of the reverse movement.

[0007] Thanks to this degree of freedom, the locking panel, which preferably includes reliefs housed between the bars, can be provided with flaps to mask each bar, the external surface of each of the aforementioned flaps being continuous with the convex external surface of these reliefs. Thus, when the panel is in its first state, the access face of the ladder is practically without a solution of continuity and therefore without any roughness that can be used for climbing it.

[0008] Furthermore, in this first state of the condemnation panel, the panel is firmly attached to the ladder, which reduces the risk of it being unintentionally detached, for example in the event of a storm for external ladders such as those on station platforms.

[0009] There may be three modes of connection by articulation of a rear anti-access panel, respectively around an upper transverse axis, around a lower transverse axis and around a lateral axis. The general structure of a ladder according to the invention is revealed, in its three variant embodiments, in particular by document FR-A-3.114.604 and particularly its figures 7 à 9 .

[0010] In the case of a lateral articulation, parallel to one of the uprights of the ladder, made by hinges, the aforementioned degree of freedom is obtained by the relative sliding of the knuckles and pins of the hinges between a close state of these corresponding to the locking position of the ladder and a separated state corresponding to all the other positions of the panel. This type of stepped hinge is known in itself.

[0011] In the case of a transverse articulation, the articulation is located at the end of lateral arms extending the panel so that the rungs of the ladder, close to this articulation, are accessible to the user's feet, whether the ladder is locked or not.

[0012] In this first embodiment of the invention, the aforementioned degree of freedom is achieved by an axis, fixed relative to one of the panel / ladder elements and housed in a slot of the other element, the longitudinal direction of which extends parallel to the plane of the latter. In an alternative embodiment, the aforementioned degree of freedom is obtained by the telescopic construction of the aforementioned arms.

[0013] The articulation of the panel to the scale can be either in high parts ( figure 1 ) either in the lower part ( figure 2 ). The device according to the invention comprises a lever for operating the panel articulated to the latter around an axis orthogonal to the uprights of the ladder, and bearing on a stop secured to the ladder to generate a movement of elevation of the panel before its pivoting relative to the ladder.

[0014] The above-mentioned lever is housed between one edge of the panel and the adjacent upright of the ladder

[0015] In a preferred embodiment of this feature, the stop is constituted by one of the rungs of the ladder.

[0016] The articulation, at the panel, of the lever of its operation is located, in the first state mentioned above, at a level lower than that of the rung on which the lever rests so that by lowering the lever the panel is raised, thus allowing its release towards the rear by pushing the lever through the plane of the ladder.

[0017] This lever has, in a position remote from its articulation, a notch in which the rung on which it slid when the ladder was unlocked is housed. This position is recorded by placing a padlock between the lever and a tab attached to the ladder upright.

[0018] It should also be noted that, in the first state (locking of access) of the panel, the lever is raised between the upright and the panel and is also locked in this position by means of the same padlock between the lever and the aforementioned tab.

[0019] Furthermore, the lever has, at its end near its articulation, a conformation which, at the end of lifting, hooks the bar on which it slid and rested when locking access.

[0020] Finally, the lever has an intermediate notch, facing the bar, to constitute a stop for retaining the panel after the start of the unlocking phase.

[0021] It is understood that the lever described above is adaptable to a panel articulated on the ladder, around a transverse axis located either in the upper part or in the lower part of the panel. In the case of a lower articulation, the aforementioned lever acts as a limiter for the spacing of the panel. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Reference will be made to the accompanying drawings in which [ Fig. 1 ] there figure 1 is a simplified view of a known ladder according to the invention with an upper articulation of the panel on the ladder, [ Fig. 2 ] there figure 2 is a simplified view of a known ladder with a lower hinge of the panel on the ladder, [ Fig. 3 ] there figure 3 is a simplified view of a known ladder with a lateral hinge of the panel on the ladder, [ Fig. 4 ] there figure 4 is a scaled diagram of the panel articulation, [ Fig. 5 ] there figure 5 is a partial side view, in which one of the ladder uprights is not shown, showing a ladder according to a first embodiment, the ladder being in a locked state, [ Fig. 6 ] there figure 6 is a partial side view, in which one of the uprights of the ladder is not shown, showing the ladder according to the first embodiment, the ladder being in an unlocked state, [ Fig. 7 ] there figure 7 is a partial side view, in which one of the ladder uprights is not shown, showing the ladder according to the first embodiment, the ladder being in an intermediate state, [ Fig. 8 ] there figure 8 is a diagram illustrating a second embodiment of the invention, applied to a panel laterally hinged to the ladder, the ladder being in a locked state, [ Fig. 9 ] there figure 9 is a diagram illustrating this second embodiment of the invention, the ladder being in an intermediate state between the locked state and an unlocked state, [ Fig. 10 ] there figure 10 is a diagram of a hinge adapted to the scale of figures 8 And 9 .

[0023] To the figure 1 , a ladder 1 is shown comprising two uprights 2 and 3 and rungs 4 extending perpendicularly between the uprights 2 and 3, thus defining two faces, namely an access face A and a rear face B. In this case, it is a fixed inclined ladder which has a panel 5 for locking its access, a panel articulated to the uprights 2, 3 of the latter around an upper transverse axis 6 by means of two lateral arms 7 and 8 which extend it. It will have been noted that the width of the panel 5 is less than the internal width of the ladder. The panel 5 has recesses 9 in which the rungs 4 are housed, when it is folded against the ladder.

[0024] To the figure 2 , this is a scale equivalent to that of the figure 1 in which the connection of the panel to the ladder is ensured by a lower transverse articulation of axis 6a at the end of lower lateral arms 7a, 8a. Links 9 and 10 hold the panel away from the ladder.

[0025] To the figure 3 , this is a scale equivalent to that of the figures 1 And 2 in which the connection of the panel to the ladder is ensured by a lateral articulation around an axis 6b.

[0026] This type of scale is known in particular from document FR 3.114.604 and particularly from the figures 7 à 9 of this document.

[0027] The diagram of the figure 4 illustrates the adaptation, noted Z, of the invention on the scale of the figure 1 , according to which the articulation axis 6, carried by the arms 7 and 8 of the panel 5 of the figure 1 , is mounted in a light 11 formed in plates 11a, integral with the uprights 2, 3 of the ladder, to slide parallel to the plane of the ladder so that a movement of this axis in the light is possible between a low position reached under the effect of gravity and a position distant from it, under the effect of a lifting force applied to the panel 5.

[0028] A structural inversion of this connection produces the same effect. Thus, the axis can be carried by the ladder 1 and the light provided at the end of each of the arms 7 and 8 in a direction parallel to the plane of the panel.

[0029] This degree of freedom is exploited in a scale according to the figures 5 à 7 . This ladder has a panel 5 with flaps 5a, adapted to cover the rungs 4 of the ladder in the locked position (the flaps 5a extend in front of the face of the rungs 4 facing the access face A of the ladder). The operation of the panel 5 is ensured according to the invention by means of a lever 12, made of cut sheet metal, articulated at 13 in the vicinity of one of its ends, on one of the sides of the panel around a transverse axis so as to be able to pivot in the free space between the panel 5 and an adjacent upright of the ladder (the one not shown). The other end of the lever is shaped as a handle 14 for its operation by a user. The profile of this lever is such that its edge facing the operator, which is the lower edge when the ladder is unlocked, defines, beyond the axis 13 relative to the handle, a hook 15, then in the direction of the handle, a first stop 16 and finally, near the handle, a second stop 17.

[0030] The other edge of the lever has a notch 18.

[0031] To the figure 5 , the lever is housed in the thickness of the ladder. The rung 4a of the ladder located in the vicinity of the axis 13 and below this axis, is hooked by the hook 15. The panel 5 is then held against the rear face B of the ladder. An orifice 19 made in the nose of the hook can accommodate the handle of a padlock not shown which also passes through a tab 20 (drawn in ghost) secured to the upright of the ladder near the lever. Access to the ladder is thus blocked for any user who does not have the key or the code of the padlock.

[0032] Once the padlock is removed by the authorized user, the latter grasps the handle 14 and pulls it downwards. The lower edge of the lever disengages from the bar 4a and bears on the latter, which causes the panel 5 to rise, the flaps 5a of which can pass above the bars. The panel 5 can then be pushed backwards, the lever sliding on the bar 4, until the movement is blocked by the stop 16. This, optional, has the advantage of limiting the pivoting of the panel under its own weight and / or under the effect, for example, of wind resistance. The user can release the stop 16 by lifting the lever to continue unlocking as illustrated by figure 7 . At the end of this movement ( figure 6 ), the lever 12 hooks the rung 4 by its second stop 17. A second orifice 21 of the lever 12 can then be located opposite the orifice of the tab 20 and once again accommodate the handle of the padlock that the user has. The unlocking of the ladder is then recorded, to prevent, for example, an untimely re-locking from occurring while the user is on the ladder.

[0033] After use, the user folds the panel against the ladder by pulling the lever 12 towards him and lifting the panel at the end of the operation as for unlocking to span each rung by the flaps 5a and finally raise the lever to place it in its state of figure 5 . It will be noted that notch 18 allows the presence of a bar in the lever storage space to be taken into account.

[0034] The association of a lever according to the invention with a scale according to the figure 2 , that is to say in which the panel is hinged to the ladder by its lower part, is strictly identical to that described above. In this case, the lever is a limiter of spontaneous separation of the panel from the ladder, due to the action of gravity.

[0035] As for a scale according to the figure 3 , the panel can be equipped with a lever whose pivoting operation acts on a cam for lifting the panel relative to the upright of the ladder carrying the hinges, lifting permitted by the degree of freedom of the articulation according to the invention. An example of this lever is illustrated by the figures 8 And 9 .

[0036] In these figures, the elements already described bear the same references as in the previous figures.

[0037] The partial cross-sectional profile diagrams 8 and 9 are those of a ladder 1 equipped with a panel 5 hinged by hinges 22 fixed to an upright 3 of the ladder around an axis 6b. They illustrate the panel 5 folded down on the rear face B of the ladder. Means not shown ensure the locking of this panel in this state. A lever 23 is mounted hinged to the panel 5 around a transverse axis 24. This lever is housed, for example, in an interstitial space existing between the panel and the upright of the ladder. A cam 25 is fixed in rotation on the axis 24. This cam rests on a rung 4 of the ladder and the profile of its active surface is such that a rotation of the handle causes an elevation of the panel 5, an elevation permitted by the articulation hinges 22 in which the knuckles 26 (female branch) can slide on the pins 27 (male branch) without coming unhinged.This elevation H allows each flap 5a of the panel to pass above the corresponding bar 2, when the panel 5 is pushed backwards. The panel can then be moved into its unlocked state where it will be locked by means also not shown in the diagrams. The hinges are such that, once the distance H is reached, the knuckles are held at this level as soon as a rotation of the panel 5 is started.

[0038] There figure 10 is a diagram of such a hinge.

[0039] The panel is thus articulated to the scale around a single axis of rotation and is movable parallel to a longitudinal direction of the scale or panel within a height range defined by the degree of freedom in translation in this direction.

[0040] There are two decoupled movements, namely a rotational movement and a translational movement, the means allowing the rotational movement independently of the means allowing the translational movement.

[0041] Of course, the invention is not limited to the embodiments described but encompasses any variant falling within the scope of the invention as defined by the claims.

Claims

1. Device for regulated access to an upper protected area, comprising a ladder (1) extending between a lower area to which a user can freely access and said upper protected area, and a means for prohibiting or preventing the use of at least some of the rungs (4) of this ladder, this means comprising a panel (5) and means for connecting it to the ladder which maintain the panel, in a first state, applied against the rear (B) of the rungs (4) of the ladder relative to its access face (A) and in a second state distant from these rungs (4), characterized in that the aforementioned connecting means comprise a rotational articulation of the panel around an axis between its two states and have at least one limited degree of freedom, in translation parallel to the longitudinal direction of the ladder (1), which is exerted after the end of the movement of the panel when it passes from its second state to its first state and before the start of the reverse movement.

2. Device according to claim 1, in which the locking panel (5) is provided with flaps (5a) for masking the front of each bar (4).

3. Device according to claim 1 or claim 2, in which the articulation is a transverse articulation (6, 6a), located at the end of lateral arms (7, 7a, 8, 8a) extending the panel, the aforementioned degree of freedom is achieved by a fixed axis (6) relative to one of the panel (5) / ladder (1) elements housed in a slot (11) of the other element (5, 1), the longitudinal direction of which extends parallel to the plane of the latter (5, 1).

4. Device according to one of claims 1 or 2, in which the articulation is a transverse articulation (6, 6a), located at the end of lateral arms (7, 7a, 8, 8a) extending the panel, the aforementioned degree of freedom is obtained by the telescopic construction of the aforementioned arms.

5. Device according to one of claims 3 or 4, comprising a lever (12) for operating the panel (5) articulated to the latter around an axis (13) orthogonal to the uprights of the ladder, and bearing on a stop (4a) integral with the ladder to generate a movement of elevation of the panel (5) before its pivoting relative to the ladder (1).

6. Device according to claim 5, wherein the aforementioned lever (12) is housed between an edge of the panel (5) and the adjacent upright of the ladder (1).

7. Device according to claim 6, in which the stop (4a) is constituted by one of the rungs (4a) of the ladder.

8. Device according to claim 7, in which the articulation (13), to the panel (5), of the lever (12) is located, in the first state above, at a level lower than that of the rung (4a) on which the lever rests so that by lowering the lever (12) the panel (5) is raised, thus allowing its release towards the rear by pushing the lever (12) through the plane of the ladder (1).

9. Device according to claim 8, in which the lever (12) has, remote from its articulation (13), a stop (17) against which the bar (4a) on which it slid when the ladder was unlocked comes to bear.

10. Device according to one of claims 5 to 9, in which the lever has at its end close to its articulation, a hook-like conformation (15) which hooks the bar (4a) on which it has slid and taken support when blocking access.

11. Device according to claim 10, in which an orifice (19) is provided in the nose of the hook to accommodate a padlock handle which also passes through a tab (20) secured to the upright of the ladder adjacent to the lever.

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