FR3082530A1 - TOP-OF-QUAY PROTECTION DEVICE FOR TRANSFERRING WASTE OR OTHER OBJECTS - Google Patents

Abstract

The invention relates to a platform top protection device (1), comprising a support (2), a flap (3) pivotally mounted between a raised position and a folded position. According to the invention, means for holding (5) the flap (3) in the raised position comprise at least one stop member (50) integral with the support (2) or the flap (3), and, for each stop member (50), a movable stop (51) mounted on the other of the support (2) and the flap (3), and movable between a holding position and a release position. In the raised position, at least one gap is present between the front edge (30a) of the flap (3) and the support (2), providing access to the movable stop (51).

Description

Description

Title of the invention: PROTECTION DEVICE AT THE TOP OF A WAY FOR THE TRANSFER OF WASTE OR OTHER OBJECTS The present invention relates to a device for protecting the top of a platform allowing the transfer of waste or other objects.

The present invention finds a preferred application in the field of waste transfer, in recycling centers or on industrial sites.

The recycling centers generally include a platform forming a platform below which skips are arranged, the users thus being able to unload the waste into the skips from the platform.

To ensure the safety of users and staff of the recycling center, hereinafter collectively designated by the term "user" for the sake of brevity, it has been proposed to equip the platforms with high protection devices. to avoid any risk of a user falling.

Such a platform top protection device generally comprises a flap mounted on a support integral with the platform so as to be pivotable, about a substantially horizontal axis of rotation, between a substantially vertical raised position, in which it provides fall protection, and a folded position, in which it can be used to facilitate the transfer of waste to the bucket.

In order to effectively ensure this prevention of the risk of falling, it has been proposed to provide means for holding the flap in the raised position, by systems of the lever or bayonet type that the user of the recycling center. must operate to release the flap from its raised position and allow it to pivot to its folded position.

An example of such a holding system is described in patent LR 3,010,096 B1, in which the holding system is a locking system comprising a rod mounted movably, on a rear face of the flap, between a locking position and a unlocking position. In the locked position, the lower end of the rod extends into the housing of a fixed stop fixed to the support, and in the unlocked position the rod has been lifted out of said housing by the user, who will have grasped the rod by its upper end forming a handle, the rod then no longer opposing the pivoting of the flap.

This locking system also comprises elastic return means of the rod towards the locking position, so that when the flap is raised manually from the folded position, the rod automatically engages in the housing of the stop on arrival in the locking position. This ensures that the flap is kept in the raised position, since the risk of forgetting to lock it by the user is eliminated.

It immediately appears that such a maintenance system has the disadvantage of being insecure, however, since any user with access to the rod, whether he is a user or a member of staff of the recycling center, and can unlock the flap, in particular involuntarily, the upper end forming a handle of the rod being for this purpose exposed on the front face side of the flap so that it can be easily grasped by the user. The flap will then no longer be able to fulfill its role of fall protection.

There is therefore a need for a platform top protection device for recycling center not having this drawback.

The platform top protection device according to the present invention, which will be defined below, satisfies this need.

The Applicant Company has also noticed that this protection device could just as easily be used for the dumping of waste on industrial sites, in which case the users include site personnel, and that it could also find a more general application in the more general field of transferring objects from a quay and for which fall protection should be ensured.

The present invention therefore relates to a protection device at the top of a quay for the transfer of waste or other objects, in particular a quay for discharging waste from a recycling center or an industrial site, the protective device comprising a support intended to be secured to the quay, a fall protection flap pivotally mounted on the support, about a horizontal axis of rotation, between a raised position and a folded position, the flap having an opposite front face and a rear face directed respectively upwards and downwards when the flap is in the folded position, and means for holding the flap in the raised position, the protection device being characterized in that:

- the holding means include:

- at least one stop member which is integral with one of the support and the flap, rear face side of the flap, and

- For each stop member, a movable stop which is mounted on the other among the support and the flap and is movable between a holding position, in which the movable stop is in abutment against the respective stop member with the flap in the raised position, in order to at least prevent the flap from pivoting towards the folded position, and a release position, in which the movable stop has been moved out of contact with the stop member in order to at least less allow the flap to pivot to the folded position, the movable stop comprising a so-called actuation part by which it is movable from the holding position to the release position; and - in the raised position, at least one gap is present between the front edge of the flap and the support, a gap providing access to the actuating part of the or of a respective movable stop.

Thus, according to the present invention, it has minimized the risk that the user acts involuntarily on the part of the movable stop by which it can be actuated to release the flap from the raised position, as in the Prior art described above, because the movable stop is now protected behind the flap and the front part of the support, with restricted access defined by this interval which is also located below the flap in the raised position.

The or each interval has a height of between 0.3 cm and 8 cm, preferably between 0.3 cm and 4 cm, more preferably between 0.4 cm and 1 cm, and, for example, is 0.8 cm.

Preferably, the protective device comprises, located in the or each interval, a protective plate provided with an opening opposite the actuating part of the or a respective movable stop, the protective plate forming an additional restriction means of access to the respective movable stop.

The presence of such a protective plate eliminates any risk that the user acts involuntarily on the movable stop, since the actuation of the latter will require the introduction of an adequate instrument through said opening.

Preferably, the opening can be dimensioned to allow passage only of an elongated instrument of small dimension, for example a dish the size of a door key.

Preferably, the or each movable stop is pivotally mounted and its actuating part is, in the holding position, in contact, or in the immediate vicinity, of a part of the support, above which it is located, the movement of the movable stop from the holding position to the release position being a pivoting in the direction of rotation away from the actuating part with respect to said part of the support.

With such a configuration, the movable stop can only be moved out of the holding position by an instrument having a pointed or wedged end that the user can introduce between the actuating part and the wall of the support. so as to lift the actuating part, and therefore to move the movable stopper towards the release position. Thus, the risk of unwanted actuation of the movable stopper is further reduced, since actuation involves the use of a specific tool.

In the case where the protection device comprises more than one movable stop, one could provide separate intervals from each other, each interval being dedicated to access to a respective movable stop.

Preferably, whether the protective device includes or not one or more movable stops, a single gap is present, giving access, possibly restricted by one or more protective plates, to the or all of the movable stops, l 'interval preferably extending along the entire lower edge of the tray.

The Applicant Company has also realized that another drawback of the locking retention system is the high risk of breakage that it presents in the event of an impact with the bucket when the latter is placed below the platform. . Indeed, the flap is locked in the raised position, that is to say that it is prevented from pivoting not only in a first direction of pivoting, towards the folded position, but also in the opposite direction of pivoting. Consequently, any shock applied to the flap locked in the raised position will result in stresses at the level of the locking system and of the pivoting connecting members to the support, which are not designed to withstand such stresses. Thus, such a shock will result in the rupture of these connecting members and / or of the locking system, rendering the protection device unusable and requiring its replacement. It will be readily understood that this represents a non-negligible cost which is difficult to accept by recycling centers, all the more so since such shocks are frequent.

To overcome this drawback, it is proposed according to the present invention that the or each stop member and the respective movable stop are configured to ensure only a stop of the flap in the direction of its pivoting from the raised position towards the folded position, the flap being moreover free to pivot in the opposite direction over an angular range in the event of an impact on the rear face of the panel, preferably over an angular range ranging from 1 ° to 20 ° relative to the raised position.

In this configuration, the means for holding the flap in the raised position are means for blocking the flap, and not locking means as in the prior art, giving the flap in the event of shock an additional degree of freedom sufficient to avoid the appearance of stresses at the connection between the flap and the support, or at least reduce these stresses to an extent excluding a risk of breakage of the protection device in the event of shock unintentional grab against the flap.

The or each movable stop can be mounted movable in one or more degrees of freedom, for example in translation or in translation and in rotation.

Preferably, the or each movable stop is pivotally mounted, the displacement of the movable stop between the holding position and the release position thus being a pivoting.

Preferably, the or each movable stopper is mounted to pivot freely and has an eccentric center of gravity with respect to its axis of rotation so that the movable stopper automatically pivots under the effect of gravity towards the holding position when the flap arrives in the raised position, being provided for this purpose means for preventing the pivoting of the movable stop towards the holding position as long as the flap has not reached the raised position.

The protection device can thus have the useful function of automatic engagement of the movable stop (s) for maintaining the flap in the raised position without the need for user action other than raising the bib.

Of course, one could provide that the or each movable stopper is mounted to pivot freely, as well as return means, for example elastic, of the movable stopper towards the holding position.

Preferably, the or each stop member is integral with the flap, rear side side, and the or each movable stop is freely pivotally mounted on the support, around a horizontal axis of rotation, and has a part locking finger extending towards the rear face of the flap and against which the stop member abuts in the raised position of the flap.

However, it would be possible to provide that the or each stop member is secured to the support and that the or each movable stop is mounted on the flap.

The or each movable stop may be, seen along its axis of rotation, in the form of an L-shaped part comprising a first branch, which forms the locking finger part, and a second branch which extends it -also forward, the axis of rotation of the movable stop passing through the transition zone between the first and second branches, and if necessary the free end of the second branch is of larger dimension so that the center of gravity of the L-shaped part is eccentric in front of its axis of rotation.

Advantageously, the or each stop member is in the form of a ring sector, a first end of which forms a first stop face, against which the respective movable stop is in abutment in the holding position. with the flap in the raised position, and the second end of which has an external shoulder forming a second stop face, against which the mobile stop is in abutment when the flap is in the folded position, the mobile stop moved in the release position , sliding on the radially outer face of the ring sector when the flap pivots between the raised position and the folded position, the ring sector thus forming said means for preventing the pivoting of the movable stop towards the holding position as long as the mud flap has not reached the raised position.

Another advantage of the above configuration of the stop member is that it does not allow agglomeration of material between the different parts, and therefore the risk of malfunction, since the movable stop is always in contact with the stop member, whatever the position of the plate.

Equally advantageously, it does not allow the jamming of members, such as fingers, hands, arms.

Advantageously, the protection device according to the present invention may comprise means for braking the pivoting of the flap from the raised position to the folded position, these braking means preferably comprising at least one torsion spring. the longitudinal axis of which coincides with the axis of rotation of the flap and the first end of which is secured to the support and the second end of which is formed by a branch extending upwards in contact with or facing the rear face of the flap in the raised position, so that the pivoting of the flap from the raised position to the folded position causes the spring to twist, which it opposes.

The flap being relatively heavy, generally between 15 kg and 120 kg, providing such braking means can accompany the tilting of the flap from the raised position to the folded position and relieve the user in his effort to retain the bib. In the case of the recycling center staff, who often have to handle the flaps, this greatly reduces the risk of musculoskeletal disorders.

We will now describe below a particular embodiment of the present invention, with reference to the accompanying drawings.

In these drawings:

[Fig.l]: perspective view, from the front side, of the protection device according to a particular embodiment of the present invention, with the flap in the raised position.

[Fig.2]: perspective view similar to Ligure 1, the flap being in the folded position.

[Fig.3]: vertical cross-sectional view of the protection device with the flap in the raised position.

[Fig.4]: vertical cross-sectional view of the protection device with the flap in the folded position.

[Fig.5]: perspective view of the protection device from the rear side, with the flap in the raised position.

[Fig.6]: perspective view similar to Ligure 5, the protective casing having been omitted.

[Fig.7]: detail view of Ligure 6, showing the means for locking the flap in the raised position.

[Fig.8]: detail view of Ligure 3, showing said locking means in their holding position.

[Fig.9]: detail view of Figure 3, showing said locking means in their release position, the flap being still in the raised position.

[Fig.10]: detail view of Figure 3, showing said locking means in their release position, the flap being in the folded position.

If we first refer to Figures 1 to 5, we can see that a protective device 1 according to a particular embodiment of the present invention conventionally comprises a support 2 to which a flap 3 is articulated, by a pivot link 4, so as to be pivotable between a raised position and a folded position, the flap 3 being able to be held in the raised position by holding means 5.

In the following detailed description below, the terms "front" and "rear" refer to characteristics, if necessary with the flap in the raised position, located respectively on the quay side Q where Γ user is located and tipper side (not shown).

The support 2 is here a mechanically welded structure comprising a base 20 from which two uprights 21 between which extends a filling plate 22 and at the upper ends of which the flap 3 is articulated.

More particularly, the base 20 is here a U-shaped profile which is fixed to the edge of the quay Q by any suitable means, such as by pins, and whose opening is oriented upwards.

Each upright 21 is in the form of a vertical flat plate delimited by a front edge which comprises a first part 21a in a straight line from the lower end of the upright 21, a second part 21b inclined towards the front and down and a third part 21c in a straight line to its upper end from which extends an upper edge 21d, which here has a recess before joining the rear edge 21e which is in a straight line until at the lower end of the upright 21. The upper end region of the upright 21 is therefore wider than its lower end region, which is received inside said U-shaped profile and is fixed to it by any suitable means, like for example by bolts.

The filling plate 22 fills the space between the two uprights 21 so as to avoid any risk of falling, and it consists of a sheet folded so as to have a first vertical and flat part 22a extending along the first parts 21a of the uprights 21, a second part 22b inclined so as to extend along the second parts 21b of the uprights 21. This sheet also has a third part 22c extending over a small distance along the third parts 21c of the uprights 21 and a fourth part 22d, the upper face of which is inclined forward, along the inner faces of the uprights 21, until reaching the upper edges 21d in its rear end region.

The flap 3 is here, in a conventional manner, a sheet 30 folded at right angles along its front edges 30a and rear 30b, and which is reinforced by reinforcing means 31 comprising in particular a transverse bar welded on the face rear 30c of the sheet 30 (Figures 5 and 6). The front face 30d of the sheet 30 is flat so that it can be used to facilitate transfer to the bucket.

It is emphasized here that the flap 3 is mounted on the support 2, in the manner which will be explained below, in a position such that the front edge 30a of the flap 3 is at a distance above the third part 22c, as well as the region of the fourth part 22d in the vicinity thereof, so as to provide an interval by which the user can access the holding means 5.

If we also refer to Figures 6 and 7, we can see that, in this embodiment, the holding means 5 are locking means comprising a stop member 50 integral with the flap 3 and a movable stop 51 pivotally mounted on the support 2.

The stop member 50 is in the form of a generally annular part from which a sector would have been removed only on the circumferential part of the part, so that this part offers a first face 50a and a second face 50b (Figure 10), both radial, the functions of which will be explained below. The stop member 50 is fixed to the rear face 30c of the flap 3 by any suitable means, such as by welding, and may have for this purpose, as illustrated in the drawings, one or more flats for a flat contact against the flap 3.

Here, the stop member 50 is located along a side edge of the flap 3, near its front edge, and it also serves for the pivot connection 4 on this side, which comprises a pivot 40, a first end of which is made integral with the upper end region of the corresponding upright 21 by any suitable means well known per se, the pivot 40 passing through the central hole of the annular part forming the stop member 50 then s' extending along the front edge of the flap 3, its second end being mounted to pivot freely in a hole in a fixing lug 32 secured to the rear face 30c of the flap 3. The axis of the pivot 40 is perpendicular to the plane of the plate forming the upright 21, and is therefore horizontal and perpendicular to the front-rear direction of the protection device L On the other upright 21, the pivot link 4 can comprise any mechanical structure allowing the flap 3 to pivot around the same axis as pivot 40.

The stop member 50 also has an outer shoulder 50c, extending radially from the circumference of said annular part, in the vicinity of the rear face 30b of the flap 3. The function of this outer shoulder 50c will be explained below.

The movable stop 51 here consists of an L-shaped part formed by a first branch 51a and a second branch 51b joining in a transition zone in which is provided a through hole for the passage of a pivot 52 also extending in a through hole provided for this purpose in the upright 21, so that the movable stop 51 is mounted to pivot freely. In particular, the axis of the pivot 52 is parallel to the axis of the pivot 40.

The first branch 51a forms the locking finger while the second branch 51b, in particular its free end, forms the actuating part of the movable stop 51.

In this embodiment, the free end of the second branch 51b is larger so as to offset the center of gravity of the movable stop 51 in front of its axis of rotation. Thus, in the absence of external actions other than gravity, the movable stop 51 will pivot, by its sole weight, counterclockwise if we look at Figures 8 to 10.

In this embodiment, the various elements of the protection device 1 are dimensioned and arranged so that, when the flap 3 is in the raised position as shown in Figures 7 and 8, the first face 50a of the member d 'stop 50 is in abutment against the free end face of the first branch 51a of the movable stop 51, without this support leading to a pivoting of the movable abutment 51 clockwise. In this embodiment, this is obtained by the configuration of the shape and of the position of the center of gravity of the movable stop 51, as well as the position of its axis of rotation, so that the result of the bearing force of the stop member 50 on the free end face of the first branch 51a passes through the axis of rotation of the movable stop 51 or is offset from the latter by a distance not allowing the application of a greater torque than that resulting from the weight of the movable stop 51 alone.

The first face 50a therefore constitutes the stop face of the stop member 50.

In addition, in the raised position, the free end of the second branch 51b is located in the vicinity of the upper face of the fourth part 22d.

It is therefore found that the holding means 5 effectively allow the locking of the flap 3 in the raised position, preventing it from returning to the folded position.

If we refer again to Figures 6 and 7, we can see that the braking means 6 are mounted around the pivot 40, formed by a torsion spring 60 including a first end branch 60a is made secured to the support 2 by any suitable means, such as by a bolt, and a second end branch 60b is folded so as to extend upwards, when the flap 3 is in the raised position.

The holding means 5 and the braking means 6 are hidden by a protective casing 7, visible in Figure 5 and not shown in Figures 6 and 7.

The protective casing 7 comprises a front plate 70, a side plate 71 and a rear plate 72 extending from the fourth part 22d of the filling plate 22 so as to laterally surround the holding means 5 and the locking means 6. If we refer to Ligure 1, we can see that the front plate 70 is provided with an opening 70a opposite the free end of the second branch 51b of the movable stop 51, this opening 70a being advantageously dimensioned so as to allow passage only of an elongated instrument 8, such as for example a dish the size of a door key or the like, for unlocking the flap 3 outside the folded position.

The front plate 70 and its opening 70a thus constitute means of additional restriction of access to the movable stop 51 via the gap between the front edge 30a of the flap 3 and the support 2.

Thus, if the flap 3 must be released from its raised position, for the transfer of waste or other objects, only a user with the appropriate instrument 8 can access the movable stop.

As illustrated in Ligure 8, the user must first of all present the instrument 8 in front of the opening 70a, then, as illustrated in Ligure 9, introduce it into the protective casing 7 and the use to lift the second branch 51b of the movable stop 51, thereby pivoting the latter clockwise. This pivoting brings the end face of the first branch 51a out of contact with the first face 50a of the stop member 50, the movable stop 51 then being in a release position. The flap 3 can then pivot towards the folded position, the movable stop 51 no longer opposing it.

After such a pivoting of the flap 3 over a few degrees, the user having removed the instrument 8 from the protective casing 7, since the movable stop 51 will seek to return to the holding position due to the gravity, the first branch 51a will come into contact with the outer circumferential face 50d of the stop member 50, between the first face 50a and the outer shoulder 50c. The movable stop 51 is thus prevented from returning to the holding position throughout the pivoting of the flap 3 until the folded position, shown in Ligure 10.

During this pivoting, the flap 3 will come to press on the second end branch 60b of the torsion spring 60 and the latter will offer resistance to pivoting, making it possible to ensure braking of the flap 3.

In Ligure 10, we can see that in the folded position the first branch 51a is in contact against the face 50d of the stop member 50 and against the radial face offered by the outer shoulder 50c, so that the movable stop 51 is well maintained in a release position.

The flap 3 remains in this folded position by its only weight.

It can be emphasized here that, in this embodiment, there is provided, on the inner face of the upright 21 carrying the movable stop 51, a fixed stop 53 positioned so as to extend on the trajectory of the first and second faces 50a, 50b of the stop member 50. Here, this fixed stop 53 is in particular positioned so that in the folded position said first face 50a is in contact with the fixed stop 53. The fixed stop 53 thus constitutes a stop limit switch for the flap 3 in its pivoting towards the folded position.

When it is desired to return the flap 3 to the raised position, the user just has to lift it by hand. It will easily be understood that, as soon as the flap 3 has reached the raised position, the face 50d of the stop member 50 no longer opposes the pivoting of the movable stop 51, and the movable stop 51 will automatically be placed, by its sole weight, in the holding position as illustrated in Figures 7 and 8.

It can also be emphasized here that, in this embodiment, the fixed stop 53 is also positioned so that in the raised position, the second face 50b of the stop member 50 is in contact against the stop fixed 53, as can be seen in Figure 7, and therefore opposes the continued pivoting of the flap 3 forward. The flap 3 is thus locked in the raised position.

We can just as easily configure the fixed stop 35 and / or the stop member 50 so as not to obtain this locking, but to leave the flap 3 free to pivot forward in the event of an impact on the face rear 30c of the flap 3, for example at a maximum angle of 20 ° relative to the raised position.

It is understood that the particular embodiment which has just been described has been given by way of non-limiting indication and that modifications can be made without departing from the scope of this document. invention.

Claims (1)

[Claim 1] [Claim 2] [Claim 3] claims Protective device (1) from the top of a quay (Q) for transferring waste or other objects, in particular a quay for discharging waste from a recycling center or an industrial site, the protective device (1) comprising a support (2) intended to be secured to the platform (Q), a fall protection flap (3) pivotally mounted on the support (2), around a horizontal axis of rotation, between a raised position and a folded position, the flap (3) having an opposite front face (30d) and rear face (30c) directed respectively upwards and downwards when the flap (3) is in the folded position, and means (5) for maintaining the flap (3) in the raised position, the protection device (1) being characterized in that: - the holding means (5) include: - at least one stop member (50) which is integral with one of the support (2) and the flap (3), rear face side (30d) of the flap (3), and - For each stop member (50), a movable stop (51) which is mounted on the other among the support (2) and the flap (3) and is movable between a holding position, in which the movable stop (51) abuts against the respective stop member (50) with the flap (3) in the raised position, in order at least to prevent the flap (3) from pivoting towards the folded position, and a position of release, in which the movable stop (51) has been moved out of contact with the stop member (50) in order to at least allow the flap (3) to pivot towards the folded position, the movable stop (51) comprising a part (51b) called actuation by which it is movable from the holding position to the release position; and - in the raised position, at least one gap is present between the front edge (30a) of the flap (3) and the support (2), gap providing access to the actuating part (51b) of the or d 'a respective movable stop (51). Protective device (1) according to claim 1, characterized in that the or each gap has a height of between 0.3 cm and 8 cm, preferably between 0.3 cm and 4 cm, more preferably between 0 , 4 cm and 1 cm, and, for example, is 0.8 cm. Protective device (1) according to any one of claims 1 and 2, characterized in that it comprises, located in the or each interval, a protective plate (70) provided with an opening (70a) in looking at the actuating part (51b) of the respective movable stop (51), the protective plate (70) forming an additional means of restricting access to the respective movable stop (51). [Claim 4] Protective device (1) according to any one of claims 1 to 3, characterized in that the or each movable stop (51) is pivotally mounted and its actuating part (51b) is, in the holding position, in contact with, or in the immediate vicinity of, a part (22d) of the support (2), above which it is located, the movement of the movable stop (51) from the holding position to the release position being pivoting in the direction of rotation moving the actuating part (51b) away from said part (22d) of the support (2). [Claim 5] Protective device (1) according to any one of claims 1 to 4, characterized in that the or each stop member (50) and the respective movable stop (51) are configured to ensure only a stop of the flap (3) in the direction of its pivoting from the raised position to the folded position, the flap (3) being moreover free to pivot in the opposite direction over an angular range in the event of an impact on the rear face (30c) of the flap (3), preferably over an angular range from 1 ° to 20 ° relative to the raised position. [Claim 6] Protection device (1) according to any one of Claims 1 to 3 and to Claim 5 taken in dependence on any one of Claims 1 to 3, characterized in that the or each movable stop (51) is mounted pivoting, the movement of the movable stop (51) between the holding position and the release position thus being a pivoting. [Claim 7] Protective device (1) according to claim 6, characterized in that the or each movable stop (51) is mounted to pivot freely and has a center of gravity eccentric with respect to its axis of rotation so that the movable stop (51 ) automatically pivots under the effect of gravity to the holding position when the flap (3) reaches the raised position, being provided for this purpose means (50) to prevent the pivoting of the movable stop (51) towards the holding position until the flap (3) has reached the raised position. [Claim 8] Protective device according to claim 6 or 7, characterized in that the or each stop member (50) is integral with the flap (3), rear side side (30c), and the or each movable stop (51) is freely pivotally mounted on the support (2), around a horizontal axis of rotation, and has a locking finger part (51a) extending in direction of the rear face (30c) of the flap (3) and against which the stop member (50) abuts in the raised position the flap (3). [Claim 9] Protective device (1) according to claim 8, characterized in that the or each movable stop (51) is, seen along its axis of rotation, in the form of an L-shaped piece comprising a first branch (51a) , which forms the locking finger part, and a second branch (51b) which also extends forward, the axis of rotation of the movable stop (51) passing through the transition zone between the first and second branches (51a, 51b), and where appropriate the free end of the second branch (51b) is of larger dimension so that the center of gravity of the L-shaped part is eccentric in front of its axis of rotation. [Claim 10] Protective device (1) according to any one of claims 8 and 9, characterized in that the or each stop member (50) is in the form of a ring sector of which a first end forms a first stop face (50a), against which the respective movable stop (51) abuts in the holding position with the flap (3) in the raised position, and the second end of which has an external shoulder (50c) forming a second stop face, against which the movable stop (51) is in abutment when the flap (3) is in the folded position, the movable stop (51), moved to the release position, sliding on the radially outer face of the sector ring when the flap (3) pivots between the raised position and the folded position, the ring sector thus forming said means for preventing the pivoting of the movable stop (51) towards the holding position while the flap (3 ) did not have reached the raised position. [Claim 11] Protective device (1) according to any one of claims 1 to 10, characterized in that it comprises means (6) for braking the pivoting of the flap (3) from the raised position to the folded position, these braking means (6) preferably comprising at least one torsion spring (60) whose longitudinal axis coincides with the axis of rotation of the flap (3) and of which a first end (60a) is integral with the support (2) and a second end of which is formed by a branch (60b) extending upwards in contact with or facing the rear face (30c) the flap (3) in the raised position, so that the pivoting of the flap (3) from the raised position to the folded position causes the spring (60) a torsion which it opposes. 1/10