EP0627527A1 - Means for supporting street furniture, retractable by electronic means - Google Patents

Abstract

This device comprises: a fixed casing (1) installed in the ground; a movable contrivance (5), housed in this casing, including, in the upper part, a plate supporting the street furniture element (4), this contrivance being able to move between a high position, in which this street furniture element emerges from the casing above the ground level, and a low position in which the street furniture element is retracted inside the casing so that its upper part does not extend beyond ground level; an electric gear motor (6, 7); and a transmission, in order to convert the rotational movement of the gear motor into a translational movement of the movable contrivance between its high position and its low position. According to the invention, the gear motor and the transmission form a reversible assembly such that, in the absence of power or of braking or locking applied to the outside of this assembly, the movable contrivance descends by itself, under gravity, back to its low position. <IMAGE>

Description

The invention relates to a device for supporting an element of retractable street furniture with an electric actuator.

In the following description, for the sake of simplicity, we will mainly consider the example of a retractable terminal, for example intended, depending on whether it is retracted or not, to authorize or prohibit access to a specific urban area; but this example should in no way be considered as limiting, the teachings of the invention can be applied to other elements of retractable street furniture of very varied types such as signboards, technical boxes, containers, dustbins, etc.

The retractable bollard support devices (or other element of retractable street furniture), when they include an actuator, fall into two types, namely on the one hand the devices with electro-pneumatic or electro-hydraulic actuator, actuated by a cylinder supplied with pressurized fluid by a compressor, and on the other hand electro-mechanical devices - category to which the present invention relates.

Such an electric actuator device is for example described in FR-A-2 650 009, which describes a box installed in an excavation of the ground and housing a retractable terminal whose deployment is controlled by an electric actuator of the "electric jack" type , that is to say in which an electric motor actuates a movable rod by means of a mechanism of the screw-nut or worm type. This actuator (which includes the electric motor, the reduction gear, the transmission, etc.) is placed in the low position, at the bottom of the box, and the movable, vertical rod is turned upwards and connected to a lifting plate carrying the thick headed.

This device of the prior art, taking into account a certain number of limitations inherent in its structure, does not make it possible to respond to the increasingly severe constraints imposed, inter alia, by local authorities for this type of device.

First, it is considered that such a device should not not require deep excavation of more than 80 cm, to avoid any risk of encounter with pipes, cables, etc. This therefore imposes a maximum compactness of the device, especially if it is desired that, in the deployed position, the bollard or the element of urban furniture has a sufficient height to allow it to play its role of obstacle. In this regard, the device of FR-A-2 650 009, due to its structure in which the actuator located at the bottom of the box is surmounted by the movable plate supporting the terminal, limits the possible height of the terminal to a value less than half the depth of the hole receiving the box, which is particularly restrictive; thus, the text of this document cites as a typical value an excavation depth of one meter for a terminal height of 400 mm - proportions inappropriate for most situations.

Secondly, the civil security constraints impose that the terminal can operate in "positive security", that is to say that in the event of a power cut, in particular in the event of a breakdown of the distribution network, a terminal in the raised position immediately descends and of itself in the retracted position, for example to allow unimpeded passage of emergency services. The retractable electrical terminal device of the aforementioned document does not meet this requirement, the terminal being only, in the event of a breakdown, retractable by hand (i.e. a person must actuate a mechanical device provided for this purpose on the terminal to bring it back into its box); "positive security" in the sense indicated above would require, if we wanted the terminal to automatically return to its retracted position in the event of a power failure, the installation of backup batteries and a detection system a cut in the mains supply; such additional equipment would complicate both the design and maintenance of the terminal (in particular because of the batteries) and would increase the cost significantly, without however providing total reliability - true positive security must be obtained without use of backup batteries.

Third, it is very desirable that the speed of deployment or retraction of the terminal is high, typically of the order of two seconds in one direction as in the other. The electro-pneumatic terminals perfectly meet this requirement; on the other hand, the known electrical terminals do not allow such rapidity to be achieved, their deployment or retraction speed being typically of the order of eight seconds, that is to say four times higher.

Fourth, it is essential that the device be protected against the risks of immersion due to an accumulation of water or mud at the bottom of the box. The bottom of the box is indeed the region most exposed and most likely to collect unwanted infiltration, despite the precautions generally taken to ensure the evacuation of fluids; to do this, the device of the aforementioned document describes a complex structure intended to provide reinforced insulation of the motor and of the other parts of the electric actuator, all situated at the bottom of the box, in particular by a structure in concentric telescopic tubes coming to protect the actuator located in axial position.

Fifth, taking into account the very variable needs of users, it seems desirable to be able to equip the support device with terminals or other pieces of street furniture of very varied types according to demand, while keeping the same universal basic support. . It is also desirable to be able to change the terminal without difficulty, for example after a collision, without having to change the entire device. This requires having a lifting support structure which is essentially independent of the structure of the terminal - which is not the case with the device of the aforementioned document, where the design mentioned above in concentric telescopic tubes intimately mixes the structure of the terminal to that of the lifting device.

Sixth, it appears desirable in practice to be able to supply the device directly with mains voltage (220 V), and not at low voltage (12 or 24 V), in order to avoid transformers, rectifiers, safety buffer power supplies with battery (see above), etc. Direct supply by mains voltage however, imposes a structure which, intrinsically, avoids the electrical risks linked to this direct supply. Here again, the device of the aforementioned document, given its structure where the electrical members are at the bottom of the box, obliges to provide for the crossing of a multitude of walls by cable glands, which complicates the production and does not provide however, not maximum security due to the possibility of infiltration at all levels.

Finally, it goes without saying that, given their context of use, all these devices must have a very high robustness and reliability despite the conditions and severe rates of use, typically 600 daily operations with peaks greater than 120 operations per hour.

The various requirements that we have just outlined are in fact so restrictive that, until now, no electric retractable bollard has been able to meet all of them.

It is for this reason that to date retractable electro-pneumatic terminals largely dominate the market, despite their greater complexity (due to the presence of a transformation of electrical energy into pneumatic energy by a compressor) and maintenance. and a more delicate installation (because it is necessary to call on people familiar with the technology of pneumatic devices).

The object of the invention is to propose a device for supporting elements of retractable street furniture, such as a retractable bollard, with an electric actuator, which meets all of the aforementioned requirements and in particular that of positive safety, while having a structure that is both simple and robust, therefore inexpensive and reliable.

The device of the invention is of the general type described in the aforementioned FR-A-2 650 009, that is to say comprising: a fixed box, installed in the ground; a mobile unit, housed in this box, comprising in the upper part a support plate for the street furniture element, this team being movable between a high position, where this street furniture element emerges from the box above ground level, and a low position, where the element of street furniture is retracted inside the box so that its upper part does not exceed ground level; an electric gear motor; and a transmission, for converting the rotational movement of the gear motor into a translational movement of the moving element between its high position and its low position.

According to the invention, it is characterized in that the gear motor and the transmission form a reversible assembly, such that, in the absence of power to the engine and of braking or locking applied from the outside to this assembly, the the mobile unit descends by itself by gravity to its low position.

• le moto-réducteur est porté par l'équipage mobile ;
• le moto-réducteur comporte un frein d'arbre à commande électrique, dit "à appel de courant", c'est-à-dire activé en permanence après que l'équipage ait atteint sa position haute et tant qu'une tension d'alimentation électrique du dispositif est disponible en amont de ce dernier ;
• la transmission comprend au moins un un organe linéaire déformable d'entraînement tel que câble, sangle, courroie ou chaîne à rouleaux coopérant avec l'arbre de sortie du moto-réducteur et dont l'une au moins des extrémités est fixée en un point haut du caisson ;
• l'autre extrémité de l'organe linéaire déformable est soit reliée à un tambour monté en sortie du moto-réducteur et sur lequel elle vient s'enrouler, soit fixée en un point bas du caisson, l'organe linéaire déformable venant en prise avec une roue menante montée en sortie du moto-réducteur ;
• l'équipage mobile est configuré en forme de cloche susceptible, en cas de submersion du dispositif, d'enfermer un volume d'air résiduel, le moto-réducteur étant monté à l'intérieur de cette cloche à un niveau lui permettant de se trouver en toutes circonstances dans ce volume d'air résiduel.

According to advantageous subsidiary characteristics:

• the gear motor is carried by the mobile equipment;
• the gear motor has an electrically operated shaft brake, called "current draw", that is to say permanently activated after the crew has reached its high position and as long as a voltage of electrical supply to the device is available upstream of the latter;
• the transmission comprises at least one deformable linear drive member such as cable, strap, belt or roller chain cooperating with the output shaft of the gear motor and of which at least one of the ends is fixed at a high point of the box;
• the other end of the deformable linear member is either connected to a drum mounted at the output of the gear motor and on which it is wound, or fixed at a low point of the box, the deformable linear member engaging a driving wheel mounted at the output of the gear motor;
• the moving part is configured in the shape of a bell capable, in the event of the device being submerged, of enclosing a volume of residual air, the gear motor being mounted inside this bell at a level allowing it to be located in all circumstances in this residual air volume.

An embodiment of the device of the invention will now be described, with reference to the appended figures.

Figure 1 shows, schematically, a retractable terminal device made according to the teachings of the invention.

FIG. 2 illustrates a possible variant of implementation of the device of FIG. 1.

Figure 3 shows another embodiment of the device according to the invention.

FIG. 4 illustrates a variant of the embodiment of FIG. 1, making it possible in particular to preserve the electrical organs of the device against the risks of flooding.

FIG. 5 schematically illustrates, seen from above, the embodiment of FIG. 1.

FIG. 6 schematically illustrates, seen from above, the embodiment of FIG. 3.

Figure 7 is an alternative embodiment of the previous embodiments.

FIG. 8 is an example of an electrical diagram of the control circuit of the device of the invention.

In Figure 1, there is shown a retractable terminal device according to the invention, where the reference 1 designates a box buried in the ground 2 so as to define a closed interior volume 3 in which can be retracted the terminal 4. This terminal is carried by a mobile assembly 5 which advantageously, in addition to its role of terminal support, also supports a motor 6 and a reduction gear 7 (visible in particular from above in FIG. 5). The reduction gear 7 is, characteristic of the invention, a reversible member consisting for example of a gear train 8, 9, 10 driving at the output a shaft 11 at the end of which is fixed, in this embodiment , a drum 12 with, preferably, with a drum at each end of the shaft, for reasons of symmetry to balance the operation of the device. On each drum 12, 12 'is wound (or unwind, in the drive direction) a respective strap 13, 13 ′ which, after passing over a respective return pulley 14, 14 ', is fixed by its end 15, 15' in the upper part of the box 1.

There are also provided (FIG. 5) means for guiding the moving element in its vertical translational movement, for example pads 16 cooperating with rails or columns 17.

According to a characteristic aspect of the invention, the engine also comprises, at the end of the shaft, an electromagnetic brake 18 whose role and control will be explained below.

Thanks to the structure that has just been described, the rotation of the drum 12 (or of the drums 12, 12 ′, if two symmetrical drums are provided) will cause the length of the strap 13 (or both to be reduced) straps 13, 13 ′) and therefore the lifting of the mobile assembly 5, and, consequently, of the terminal 4 which will thus come out of the ground.

In the opposite direction, due to the reversible nature of the reduction gear 7, the simple cutting off of the motor supply will release the drums 12, 12 ′, and the terminal will drop by itself, by gravity, in the retracted position at the bottom housing; of course, suitable damping means (not shown) can be provided to slow down the descent of the bollard and / or make its arrival at the bottom of the box less abrupt; in any event, this descent phase remains very brief, typically of the order of two seconds, and occurs as soon as the power supply is cut, without any active maneuver, which is perfectly consistent with the concept of positive security mentioned more high.

In addition, the illustrated structure ensures very high compactness, in particular as regards the overall depth of the device, which makes it possible to provide a relatively high ratio between the height of the retractable bollard and the depth of the excavation necessary for house the device, unlike the electrical devices of the prior art where this ratio was limited to a value of approximately 50%.

Regarding the climb speed, it is possible to choose, for a reasonable engine power, a reduction ratio of the reduction gear such that the lifting is operated in two seconds approximately, value in any event much lower than the times usually encountered with known electrical devices.

Finally, we see that the proposed structure is completely independent of the type of terminal or even the nature of the element of street furniture used, which is therefore very easily adaptable or interchangeable without it being in any way necessary to intervene on the various elements of the lifting device proper.

It will also be noted that the configuration of the gearmotor illustrated in FIG. 5 has two extremely interesting aspects, namely: (i) that it is reversible due to the use of a gear train instead of tangent screws (as in most reducers used in this type of gearmotor); and (ii) that it makes it possible to have an output shaft 21 parallel to the shaft 20 to the axis of the motor, which ensures the symmetry of the mechanism and also ensures better overall compactness.

For example, for a 60 kg concrete bollard lift system, a 400 W output power gearmotor powered by a 220 V single-phase asynchronous motor can be used. The nominal speed of the motor can then be 1,500 rpm / minute, giving a gearbox output of 100 revolutions / minute and a nominal torque of 35 Nm, sufficient to allow complete lifting of the terminal in less than two seconds.

As regards the strap 13, it is possible, as a variant, to replace it with another functionally similar linear deformable element, for example a simple cable, a roller chain, a toothed belt, etc.

Furthermore, it is also possible to provide a configuration such as that illustrated in FIG. 2, where the member 13, which here is preferably a roller chain or a toothed belt, is of fixed length and fixed at its two ends 15 and 19 at the top and bottom of the box. The member 12, instead of being a winding drum as in the previous embodiment, is then a toothed or toothed wheel coming into engagement with the member 13, a return pulley 14 can be provided to ensure a cooperation of organs 12 and 13 over a larger area. Wheels 12 and 14 have their axes of course integral with the moving element 5, the rotation of the wheel 12 moving this moving element 5 in vertical translation. In the same vein, the member 13 could alternatively be a rigid member such as a rack arranged from top to bottom of the box and on which the toothed wheel 12 would mesh.

Other embodiments can be envisaged, for example those illustrated in Figures 3 (elevation view) and 6 (top view): in this case, the winding of the straps 13, 13 'is done directly on the drums 12, 12 ′ without interposition of return pulleys. It will also be noted that, in this 'variant, the axis 20 of the motor and 21 of the pulleys 12, 12' are parallel and perpendicular to the plane defined by the guide rails 17 (unlike for example the configuration of FIG. 5 ).

In the variant of FIGS. 4 (elevation view) and 7 (top view), the basic structure is similar to that of FIG. 21, with drums 12, 12 'on which straps 13, 13 are wound. 'passed on pulleys 14, 14' integral with the moving assembly 5, but the latter is produced in the form of a bell comprising, under the plate supporting the terminal, a continuous side wall 22 defining a volume 23 open towards the low and likely to trap a residual volume of air even if the device is submerged (severe storm, etc.). Thus, the motor 6 and the reduction gear 7, which are mounted on a support frame 24, remain in all circumstances out of water, inside the air pocket.

We will now describe in more detail the electromagnetic brake 18, which is advantageously of the "current draw" type (that is to say which acts in blocking mode when it is supplied and in release as soon as it does not. is more). This brake, placed at the head of the motor shaft, offers very good resistance to the force exiting the reduction gear, because the reduction gear multiplies the resistance offered. We can thus be satisfied with a low voltage and low consumption brake (typically, 24 V and 7 W). This brake remains permanently supplied as long as the terminal is in the high position; in the event of a power failure, it immediately releases the motor shaft, which, due to the reversibility of the transmission, will allow the terminal to come back down in its housing by simple gravity.

FIG. 8 shows an example of a supply and control circuit for the device of the invention. This comprises two switches, namely a controlled switch (manually or automatically) 25 for triggering the lifting of the terminal (this switch then being kept closed) and a high limit switch 26, for example an inductive type sensor , which will close when the bollard has reached its top dead center and will remain closed as long as the bollard remains at this point.

The assembly can be supplied directly at 27 by the 220 V sector, especially when the embodiment of FIG. 4 is chosen, which makes it possible to be certain that in no case will the motor and its associated electrical members will be in contact with water. The sector supplies the motor 6 via a triac 29 controlled by an optocoupler 29 disposed at the outlet of a door 30 acting under control of the switches 25 and 26 (the understanding of the circuit will appear immediately to the man of the art and will not be described in more detail). As for the electromagnetic brake 18, it is supplied with low voltage by a step-down transformer 31 and a rectification and filtering circuit 32 by means of a Darlington 33 controlled by a door 34 also controlled by the position of the switches 25 and 26 in such a way that, when the terminal reaches the high position (closing of the switch 26), the circuit comes to cut the power supply to the motor and to arm the electromagnetic brake.

Claims (7)

A device for supporting an element of retractable street furniture with an electric actuator, of the type comprising: - a fixed box (1), installed in the ground, - a mobile assembly (5), housed in this box, comprising in the upper part a support plate for the street furniture element (4), this crew being movable between a high position, where this street furniture element emerges from the box at above the ground level, and a low position, where the element of urban furniture is retracted inside the box so that its upper part does not exceed the level of the ground, - an electric geared motor (6, 7), and - a transmission, to convert the rotational movement of the gear motor into a translational movement of the moving assembly between its high position and its low position,
characterized in that the gear motor and the transmission form a reversible assembly, such that, in the absence of power to the motor and of braking or locking applied from the outside to this assembly, the mobile assembly descends from itself- even by gravity at its low position. The device of claim 1, in which the gear motor is carried by the mobile assembly. The street furniture element of claim 1, in which the gear motor comprises an electrically operated shaft brake (7) permanently activated after the crew has reached its high position and as long as a voltage of electrical supply to the device is available upstream of the latter. The device of claim 2, in which the transmission comprises at least one deformable linear drive member (13, 13 ') such as cable, strap, belt or chain with cooperating rollers with the output shaft of the gear motor and at least one of the ends (15, 15 ') of which is fixed at a high point of the box. The device of claim 4, in which the other end of the deformable linear member is connected to a drum (12, 12 ') mounted at the outlet of the gear motor and on which it is wound. The device of claim 4, wherein the other end (19) of the deformable linear member is fixed at a low point of the box, the deformable linear member engaging with a driving wheel (12) mounted at the outlet of the gear motor. The device of claim 1, in which the mobile assembly is configured in the shape of a bell (22) capable, in the event of submersion of the device, of enclosing a volume of residual air (23), the gear motor being mounted inside this bell at a level allowing it to be in all circumstances in this residual air volume.

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