FR3142183A1 - method and system for anti-crush protection of an aerial platform operator and aerial platform comprising this system - Google Patents

Abstract

The method provides anti-crush protection for an operator (O) on board a work platform (3) of a lifting platform or a control console (10) allowing him to initiate a movement of the work platform. The protection method comprises the implementation of a first rule according to which the movement of the work platform (3) is stopped if the movement is in progress at the moment when a detection system detects the occurrence of a situation at risk for the operator. The method comprises the implementation of a second rule according to which the movement of the work platform (3) is executed at a reduced speed compared to a normal speed of movement if the risk situation for the operator is detected at the time of engagement of the movement at the control console (10). This differentiated treatment reduces the number of untimely stoppages of the work platform movements. Figure for abstract: Fig. 5

Description

method and system for anti-crushing protection of an operator of a lifting platform and lifting platform comprising this system

The present invention relates to the field of mobile personnel elevating platforms (also referred to by the acronym MEWP) also commonly called lifting platforms. More particularly, the invention proposes a method and a system for anti-crushing protection of an operator on board a work platform of a lifting platform, as well as a lifting platform comprising this protection system.

Aerial work platforms are machines designed to allow one or more people to work at height. To do this, they include a work platform designed to accommodate them and possibly also loads such as tools or other equipment, materials such as paint, cement, etc. The work platform includes a tray surrounded by a guardrail. It is supported by a lifting mechanism that allows it to be raised from a lowered position on the chassis of the aerial work platform to a desired working position at height.

There are a wide variety of aerial work platforms to meet the different desired uses. Thus, different technologies of the lifting mechanism of the work platform are used according to which the aerial work platforms are generally qualified, for example scissor lifts, vertical mast lifts, articulated lifts, telescopic lifts. Depending on the case, the lifting device may comprise a turret pivotally mounted about a vertical axis on the chassis in order to allow the orientation of the lifting mechanism and therefore of the work platform to be changed relative to the chassis. The aerial work platforms can also be self-propelled, i.e. motorized to allow their autonomous movement on the ground.

The work platform is equipped with a control panel allowing an operator on board the work platform to cause the work platform to move to reach the desired working position. To do this, the control panel is equipped with control devices allowing the operator to operate the lifting mechanism, but also, where applicable, the pivoting of the turret and the movement of the lifting platform on the ground.

The control console is generally mounted fixed on the guardrail or at the level of it and is designed so that the operator stands in front of it when he wishes to manipulate the control components.

In the case of scissor lifts and vertical mast lifts in particular, the control panel is sometimes designed to be movable by the operator so that it can be removably attached to different locations on the guardrail, but preferably at a front corner of the guardrail of the work platform. For this purpose, the panel is generally more compact and lighter than in the case of fixed panels. The control panel can also be designed so that the operator can hold it with one hand and operate its controls with the other, which in particular makes it possible to control the aerial work platform from the ground instead of from the work platform. In this case, the control panel is even more compact and even lighter.

When the work platform is moved by an operator at the work platform control panel, there is a risk that the operator will be crushed against the control panel by an external obstacle – for example, part of a building, a structure or a tree branch – hitting him from behind or above. The same risk may exist in relation to the guardrail in cases where the operator can stand next to the control panel while operating its control devices. This is also the case for certain movable control panels which are designed so that the operator stands next to the panel rather than in front of it when the panel is attached to the guardrail.

Protection systems have been proposed to protect the operator against this risk. Two types of solutions are mainly used nowadays.

A first type of protection system consists of mounting a fixed or mobile safety bar in front of the control panel, which is interposed between the control panel and the operator standing in front of the panel in order to manipulate its control elements. The control system of the lifting platform stops or prevents the movements of the work platform when the bar is mechanically urged towards the panel. This type of solution is illustrated in particular by FR 3 007 401 A1, EP 2 190 775 A1, JP 64-12100, JP H4-77600 U, GB 2 481 709 A1, WO 2017/098120 and WO 2020/144601.

A second type of protection system uses a non-contact detection system to detect an abnormal position of the operator relative to the control panel or another type of risky situation for the operator. A typical example is to detect too close a proximity of the operator to the control panel or possibly also too close a proximity to the guardrail on one side of the control panel. As in the first type of solutions, the operator protection system stops or prevents the movements of the work platform when the detection system detects that the operator is in an abnormal position in order to avoid a risk of crushing the operator. For example, JP 5-124800 A teaches to have optical barriers in front of and above the control panel. If the operator is pushed towards the console by an external obstacle, his body cuts off one and/or the other of the light beams in which case the corresponding receiver(s) no longer receive the light of the corresponding beam and consequently, the device stops the movements of the lifting platform. WO 2017/178737 proposes an improvement to this system which is based on the detection of an optical beam reflected by the operator instead of the non-reception of the emitted optical beam, which also allows it to be used to detect the proximity of the operator to the guardrail when he stands on a lateral side of the control console. According to another approach, US 10,358,331 B2 proposes using a stereoscopic camera with real-time image analysis. This document also proposes using a neutralization button (conventionally called an override button ) to allow movement at slow speed after having been stopped or prevented by the protection system. WO 2021/026585 proposes using a LIDAR ( Light Detection and Ranging ) system to detect an abnormal position of the operator or an abnormal acceleration of the operator's body.

In addition to these two types of protection systems, there are still others which use other means of detecting the risk of crushing the operator in order to inhibit the movements of the work platform, but they are less commonly used.

A common drawback of existing protection systems is that they stop or prevent the movements of the work platform if the operator is not sufficiently vigilant and unintentionally triggers the protection system. This is particularly true in the case of the second type of protection systems that use a non-contact detection system because the operator does not easily perceive that he can unintentionally trigger the detection. These untimely stops cause a loss of productivity. In addition, they can irritate the operator, which can cause him to become nervous and a corresponding drop in vigilance, which is not desirable.

The aim of the present invention is to provide a solution for protecting the operator on board the work platform of lifting platforms, at least partially overcoming the aforementioned drawbacks.

To this end, the present invention proposes a method for protecting an operator from being crushed on board a work platform of a lifting platform, which method is implemented automatically, the lifting platform comprising a control panel intended to be used on board the work platform and designed to allow the operator to initiate a movement of the work platform, the lifting platform further comprising a detection system for detecting a risky situation for the operator on board the work platform.

The protection method comprises: implementing a first rule according to which the movement of the work platform is stopped if the movement is in progress at the time when the detection system detects the occurrence of the risk situation for the operator; and implementing a second rule according to which the movement of the work platform is executed at a reduced speed compared to a normal speed of the movement if the risk situation for the operator is detected by the detection system at the time of engagement of the movement at the control panel.

In the method of the invention, the management of a risky situation for the operator is therefore different depending on the circumstances in which it is detected. In other words, the same risky situation for the operator is managed either according to the first rule or according to the second rule depending on whether it is the condition of the first rule or the condition of the second rule that is satisfied.

The condition of the first rule, namely whether the movement of the work platform is in progress at the time when the detection system detects the occurrence of the situation that poses a risk to the operator, usually corresponds to a significant risk to the operator. This is why the implied consequence of the first rule is the stopping of the movement in progress of the work platform, in order to avoid possible crushing of the operator. For this reason, it is preferable that the movement is stopped immediately without delay as soon as the detection system detects the occurrence of the situation that poses a risk to the operator.

On the other hand, in the context of the invention, it has been noted that the condition of the second rule, namely whether the risk situation for the operator is detected by the detection system at the time of initiating the movement at the control panel, corresponds to a low risk for the operator. Indeed, in this case, the risk situation for the operator exists at the very moment when he initiates the movement of the work platform. In other words, the movement of the work platform initiated by the operator is not the cause of the risk situation. In particular, it may be that the operator has voluntarily placed himself in the risk situation before initiating the movement of the work platform. For example, he may approach the control panel or the guardrail of the work platform at an unusually small distance in order to have a better view of the environment of the lifting platform before initiating a movement of the work platform.

It is therefore acceptable to authorize the movement of the work platform initiated by the operator when the condition of the second rule is satisfied. However, as provided for in the implied consequence of the second rule, it is prudent to authorize the movement only at a speed reduced compared to a normal speed of the movement applied in normal operation, i.e. when the risk situation for the operator is not detected. Thus, the operator can easily react and manage the risk if, despite everything, a real risk for the operator occurs after having initiated the movement of the work platform. The reduced speed is preferably less than or equal to half the normal speed of the movement concerned and is even more preferably less than or equal to a quarter or even a fifth of the latter. In cases where the speed of the movement concerned can be varied at the control panel by the operator, the maximum value of the normal speed of this movement and the maximum value of the reduced speed of this movement will be taken as a reference to apply this relationship between reduced speed and normal speed of the movement.

Since the method is implemented automatically, it will be understood that the first rule and the second rule are implemented automatically. In other words, they are applied automatically by the aerial work platform without human intervention when the aerial work platform is in operation, which ensures the effectiveness of the protection method. This also means that in the second rule, the reduced speed is applied automatically by the aerial work platform without the operator having to engage a dedicated command for this purpose such as pressing a neutralization button (or override button).

Allowing the movement initiated at the control panel under the second rule despite the detection of a risk situation advantageously makes it possible to significantly reduce the number of stops and the downtime of the work platform due to the intervention of the operator's anti-crushing protection while maintaining an excellent level of operator anti-crushing protection. This therefore results in a gain in productivity. In addition, since the implementation of the second rule is automatic, it does not cause any particular annoyance for the operator because the movement initiated at the control panel is executed immediately without requiring any additional specific action on his part.

The detection system for detecting a risk situation for the operator on board the work platform may be any type of system for detecting a potentially dangerous situation for the operator on board the work platform due to the movement of the latter. The detection system may in particular be of any type used in the operator anti-crushing protection systems for lifting platforms of the prior art. In particular, it may be any type of detection system suitable for detecting a situation of risk of crushing for the operator on board the work platform due to the movement of the latter. Conventionally, the detection is preferably carried out relative to the operator's body. A certain number of non-limiting embodiments of the detection system are mentioned below.

According to a preferred embodiment, the risk situation detected by the detection system is a position of the operator relative to the control panel. This may conventionally involve detecting a proximity of the operator to the front side and/or the top of the control panel. In other words, it involves detecting the situation where the operator moves abnormally close to the control panel relative to the position he normally occupies when using the control panel. For this, it is possible in particular to use prior art systems consisting of mounting a fixed or mobile safety bar in front of the control panel to detect a push against it. However, the protection system of the invention is even more interesting in cases where it comprises a contactless detection system because the risk of untimely triggering of the detection is greater in this case.

Additionally or alternatively, it may involve detecting a distance of the operator from the control panel. In other words, in this case it involves detecting the situation where the operator is abnormally far from the control panel compared to the position he normally occupies when using the control panel.

Additionally or alternatively, the risk situation detected by the detection system may be the proximity of the operator to a part of the guardrail that is laterally adjacent to the control panel. In other words, in this case, the aim is to detect the situation where the operator is not standing in front of the control panel, but is standing abnormally close to a part of the guardrail right next to the control panel.

According to another preferred embodiment, the risk situation detected by the detection system is the absence of the operator in a determined zone relative to the control panel on board the work platform. In other words, in this case it is a question of detecting the situation where the operator is outside an area in which the operator is normally located when using the control panel.

Additionally or alternatively, it may be a question of detecting the presence of the operator in a specific area relative to the control panel on board the work platform. In other words, in this case it is a question of detecting the situation where the operator is in an area in which the operator should not normally be when using the control panel.

Detection of the presence or absence of the operator in a given area is preferably implemented by contactless detection.

Although it is advantageously simple and effective to base the detection on a position of the operator on board the work platform or on the presence or absence of the operator in an area on board the work platform, the detection by the detection system of a risky situation may in other embodiments be based on other physical parameters such as for example an acceleration of the operator's body. In particular, it may involve detecting an acceleration of the body exceeding a given threshold. This detection may be indicative of an impact of an obstacle external to the lifting platform with the operator.

According to yet another embodiment, the risk situation detected by the detection system may be the proximity of an obstacle external to the lifting platform with the operator on board the work platform. Such detection may also be implemented by contactless detection.

In general, the detection system preferably uses non-contact detection which can be implemented by any suitable technology, for example one or more photoelectric sensors, one or more LIDAR ( Light Detection and Ranging ) sensors, one or more LADAR ( Laser Detection and Ranging ) sensors, one or more RADAR ( Radio Detection and Ranging ) sensors, one or more ultrasonic sensors and/or one or more cameras or one or more 3D vision devices with image analysis . However, the detection system can also use contact detection.

According to a preferred embodiment, the method comprises: after triggering the second rule, executing the movement of the work platform at the reduced speed as long as the movement remains engaged at the control panel, including if the detection system ceases to detect a risky situation for the operator. Triggering the second rule means the case where the movement of the work platform is executed at the reduced speed compared to the normal speed of the movement in application of the second rule because the risky situation for the operator was detected by the detection system at the time of engagement of this movement at the control panel. Maintaining the movement in progress at the reduced speed despite the cessation of detection of the risky situation for the operator avoids the risk of unbalancing the operator. Indeed, if the speed of movement of the work platform changed from the reduced speed to the normal speed, the operator could be unbalanced due to the acceleration undergone by his body.

According to another preferred embodiment, the method comprises: excluding the implementation of the first rule when the movement is in progress at the reduced speed; and after triggering the second rule, executing the movement at the reduced speed as long as the movement remains engaged at the control panel without taking into account the detection system. This embodiment advantageously makes it possible to improve productivity when a movement is in progress at the reduced speed due to the triggering of the second rule. Indeed, in the case where the risk situation for the operator ceases to be detected, then is detected again during the execution of the movement at the reduced speed, the movement in progress of the work platform is not stopped but will continue to continue at the reduced speed as long as the movement remains engaged at the control panel. This is acceptable from the point of view of operator safety because the operator can easily react and manage the risk if it is real, given that the movement is executed at the reduced speed.

According to a preferred embodiment, the method is applied with respect to a lifting movement of the work platform. In other words, the control panel is designed to allow the operator to initiate a lifting movement of the work platform and the method comprises: implementing the first rule according to which the lifting movement of the work platform is stopped if the lifting movement of the work platform is in progress at the time when the detection system detects the occurrence of a risk situation for the operator; and implementing the second rule according to which the lifting movement of the work platform is executed at a reduced speed compared to a normal speed of the movement if the risk situation for the operator is detected by the detection system at the time of initiating the lifting movement of the work platform at the control panel.

According to another preferred embodiment, the method is applied with respect to a movement of the work platform parallel to the ground which is obtained by a translation on the ground of the lifting platform. In this case, the lifting platform is self-propelled to be able to translate on the ground, the control panel being designed to allow the operator to initiate a translation on the ground of the lifting platform. And the method comprises: implementing the first rule according to which the translation on the ground of the lifting platform is stopped if the translation on the ground of the lifting platform is in progress at the time when the detection system detects the occurrence of a risky situation for the operator; and the implementation of the second rule according to which the ground translation of the lifting platform is carried out at a reduced speed compared to a normal ground translation speed of the lifting platform if a risk situation for the operator is detected by the detection system at the time of engagement of the ground translation of the lifting platform at the control console.

In this embodiment, the method may further advantageously comprise: implementing the first rule and the second rule only if the work platform is at least partially raised; and implementing a third rule according to which the ground translation of the lifting platform is authorized without taking into account the detection system on the condition that the work platform is in a completely lowered position. The implementation of this third rule is advantageous in terms of productivity because possible stops in the movement of the lifting platform on the ground due to the protection system are avoided. This is acceptable because the operator is then in the situation of a simple driver of a motor vehicle since the work platform is completely lowered, it being specified that it is usually provided in this case to be able to drive the lifting platform at high speed compared to the normal ground translation speed when the work platform is raised.

According to another preferred embodiment in which the control panel is designed to allow the operator to selectively initiate any movement among several different movements of the work platform, the method comprises: excluding at least one movement of the work platform from the implementation of the first rule and the second rule so as to authorize this movement of the work platform without taking into account the detection system. In other words, if this movement is initiated at the control panel, it will be executed at its normal speed regardless of any possible detection of a risky situation for the operator. This embodiment is advantageously applicable to any movement considered not to increase the risk for the operator, or even that it possibly allows the risk for the operator to be reduced or eliminated. The fact of not inhibiting this movement also allows a gain in productivity.

This embodiment can advantageously be applied to the downward movement of the work platform. In other words, the control panel is designed to allow the operator to initiate a downward movement of the work platform and the method comprises excluding the downward movement of the work platform from the implementation of the first rule and the second rule so as to authorize the downward movement of the work platform without taking into account the detection system.

Similarly, this embodiment can also be advantageously applied to the ground translation movement of the lifting platform in forward motion in the case where the lifting platform is self-propelled. In this case, the control panel is designed to allow the operator to initiate a ground translation of the lifting platform in forward motion and the method comprises excluding the ground translation of the lifting platform in forward motion from the implementation of the first rule and the second rule so as to authorize the ground translation of the lifting platform in forward motion without taking into account the detection system. Indeed, the risk of crushing for the operator compared to the ground translation in forward motion is very low because the operator naturally looks in the forward direction of the lifting platform in this case and therefore sees a possible external obstacle approaching him. This is especially the case when the control panel is fixedly mounted on the work platform because the mounting position of the control panel requires the operator to position himself naturally in front of it while looking towards the front of the lifting platform.

According to another preferred embodiment, at least one reset procedure executable at the control panel is provided and the method comprises: in the event of triggering of the first rule, the application of a first restricted operating mode until the reset procedure is executed; and the prohibition of movement during the entire time of application of the first restricted operating mode. Triggering of the first rule means the case where the movement of the work platform is stopped in application of the first rule because this movement was in progress at the time when the detection system detects the occurrence of the situation posing a risk for the operator. This embodiment prevents the operator from being unbalanced due to an automatic restart of the movement if the detection of the situation posing a risk for the operator ceases after having been stopped by application of the first rule.

According to an advantageous embodiment, the control panel is designed to allow the operator to selectively engage any movement among several different movements of the work platform and the method comprises for each of the movements of the work platform either the prohibition of executing the movement of the work platform during the entire time of application of the first restricted operating mode, or the authorization of executing the movement of the work platform only at a speed reduced compared to a normal speed of the movement - preferably without taking into account the detection system - during the entire time of application of the first restricted operating mode.

Thus, if during the application of the first restricted operating mode, the operator initiates a movement of the work platform the execution of which is prohibited, this movement will not be implemented by the lifting platform. Such a prohibition is preferentially applied to any movement of the work platform which is considered to potentially increase the risk of crushing for the operator when a movement in progress of the work platform has just been stopped in application of the first rule. This prevents the operator from increasing the risk of crushing by possibly accidentally initiating such a movement at the control panel.

On the contrary, the authorization to perform a movement of the work platform but only at reduced speed is preferentially applied to any movement of the work platform that is considered to potentially reduce or eliminate the risk of crushing for the operator when a movement in progress of the work platform has just been stopped in application of the first rule. Thus, the operator can cause such an authorized movement by engaging it at the control panel in order to free himself from the risky situation. Executing such a movement at reduced speed allows the operator to better control it and therefore safe management of this movement of the work platform. For this reason, it is satisfactory to allow the execution of the movement of the work platform without taking into account the detection system, which avoids the operator being bothered by stops in the movement of the work platform due for example to a new detection of a risky situation for the operator, given that the execution of the movement at reduced speed allows him a sufficiently safe management of the authorized movements of the work platform.

The prohibition on carrying out the movement of the work platform during the entire time of application of the first restricted operating mode is preferably always applied to the upward movement of the work platform because this is almost always dangerous when there is a situation with a risk of crushing for the operator. In other words, in this case, the control panel is designed to allow the operator to initiate an upward movement of the work platform and the method comprises prohibiting the upward movement of the work platform during the entire time of application of the first restricted operating mode, regardless of the movement of the work platform that was in progress at the time of triggering of the first rule.

According to an embodiment in which the lifting platform is self-propelled to be able to translate on the ground and the control console is designed to allow the operator to selectively engage a translation on the ground of the lifting platform in forward motion, a translation on the ground of the lifting platform in reverse motion, a raising movement of the work platform and a lowering movement of the work platform, the method comprises, during the application of the first restricted operating mode due to a triggering of the first rule at a time when the work platform was subjected only to a raising movement, the authorization to execute only at a speed reduced compared to a normal speed of movement any movement among the translation on the ground of the lifting platform in forward motion, the translation on the ground of the lifting platform in reverse motion and the lowering movement of the work platform. In fact, these three movements can be useful to the operator in this case to allow him to free himself from a situation where he could be crushed.

According to another embodiment in which the lifting platform is self-propelled to be able to translate on the ground and the control panel is designed to allow the operator to selectively engage a translation on the ground of the lifting platform in forward motion, a translation on the ground of the lifting platform in reverse motion, a movement of raising the work platform and a movement of lowering the work platform, the method comprises, during the application of the first restricted operating mode due to a triggering of the first rule at a time when the work platform was subjected only to a translation on the ground of the lifting platform in reverse motion, the authorization to execute only at a speed reduced compared to a normal speed of movement the translation on the ground of the lifting platform in forward motion and the movement of lowering the work platform. Indeed, these two movements can be useful to the operator in this case to allow him to free himself from a situation at risk of crushing for him.

According to a preferred embodiment in which the control panel is designed to allow the operator to selectively initiate any movement from a plurality of different movements of the work platform and in which at least one reset procedure executable at the control panel is provided, the method comprises: in the event of triggering of the second rule, applying a second restricted operating mode until the reset procedure is executed; and during the entire time of application of the second restricted operating mode, authorizing any movement of the work platform to be executed only at a speed reduced compared to a normal speed of movement. This allows the operator to freely move the work platform despite the risky situation for the operator which led to the application of the second restricted operating mode. This promotes productivity and is acceptable in terms of safety for the operator since, as explained above, the movement of the work platform initiated by the operator is not the cause of the risk situation and the reduced speed of the movement of the work platform allows him to adequately manage any potential risk of crushing himself.

It is advantageous to provide, during the entire time of application of the second operating mode, the exclusion of the application of the first rule and the authorization to execute any movement of the work platform at the reduced speed without taking into account the detection system. Since the first rule is not applied during the second restricted operating mode and the detection system is not taken into account, possible involuntary stops of the movement of the work platform that could otherwise be caused by the application of the first rule are avoided. This promotes productivity and avoids irritating the operator when the second restricted operating mode is applied.

According to a further preferred embodiment, the method comprises: when the first restricted operating mode is being applied, deactivating the first restricted operating mode in the event of execution of the reset procedure provided that the detection system has ceased to detect a risk situation for the operator; and/or when the second restricted operating mode is being applied, deactivating the second restricted operating mode in the event of execution of the reset procedure provided that the detection system has ceased to detect a risk situation for the operator. Deactivating the first restricted operating mode, respectively the second restricted operating mode, causes the return to the normal operating mode. The fact of only terminating the restricted operating modes on condition that the detection system has ceased to detect a risk situation for the operator advantageously ensures that the return to the normal operating mode takes place under safe conditions for the operator.

According to another preferred embodiment, the reset procedure comprises or consists of disengaging any movement of the work platform at the control console, the method comprising deactivating the first restricted operating mode and/or the second operating mode in the event of execution of the reset procedure provided that any movement of the work platform is disengaged at the control console and that the detection system has ceased to detect the situation at risk for the operator. In other words, the reset procedure only allows the deactivation of the first restricted operating mode and/or the second operating mode if concomitantly any movement of the work platform has been disengaged at the control console and the detection system has ceased to detect the situation at risk for the operator.

According to another preferred embodiment in which the aerial work platform comprises a turret pivotally mounted on a chassis, the turret supporting a device for lifting the work platform, the control console being designed to allow the operator to initiate a rotation of the turret, the method comprises: implementing the first rule according to which the rotation of the turret is stopped if the rotation of the turret is in progress at the moment when the detection system detects the occurrence of a risky situation for the operator; and implementing the second rule according to which the rotation of the turret is executed at a reduced speed compared to a normal speed of rotation of the turret if a risky situation for the operator is detected by the detection system at the moment when the rotation of the turret is initiated at the control console.

According to another aspect, the invention proposes a system for protecting an operator of a lifting platform comprising a work platform and a control panel intended to be used on board the work platform and designed to allow the operator to initiate at least one movement of the work platform, the protection system comprising: a detection system for detecting a risky situation for the operator on board the work platform; and a system for managing the movement of the work platform, which management system is functionally connected to the detection system, the management system being configured to implement the method for anti-crushing protection of an operator according to the invention. In practice, the work platform is movable at least in height.

The management system can be implemented by on-board electronics of the lifting platform which is designed to control the movements of the work platform and more generally the movements of the lifting platform. The management system can also be a specific electronic circuit designed to be interfaced with the on-board electronics of the lifting platform which controls the movements of the work platform and the lifting platform. This electronic circuit can be housed for example in the control panel or in a housing dedicated to the protection system, i.e. housing its detection system and its management system.

According to yet another aspect, the invention proposes a lifting platform, comprising a work platform movable at least in height and a control console intended to be used on board the work platform and designed to allow an operator to engage at least one upward movement of the work platform and one downward movement of the work platform, the lifting platform further comprising a system for protecting an operator of a lifting platform according to the invention.

According to a preferred embodiment, the lifting platform is self-propelled to translate on the ground in forward and reverse gear, the control console being further designed to allow the operator to initiate a translation on the ground of the lifting platform in forward and reverse gear.

According to another preferred embodiment, the lifting platform is a scissor lift or a fixed vertical mast lifting platform. By vertical mast lifting platform, we mean a vertical mast lifting platform which is without a pivoting turret and whose mast orientation is fixed relative to the chassis of the lifting platform on which it is mounted.

According to yet another embodiment, the lifting platform comprises a turret pivotally mounted on a chassis, the turret supporting a device for lifting the work platform, the control console being further designed to allow the operator to initiate rotation of the turret. In this case, the lifting platform is preferably a telescopic mast lifting platform or an articulated mast lifting platform or a vertical mast lifting platform with a pivoting turret.

Other aspects, features and advantages of the invention will become apparent from the following description of preferred embodiments of the invention, given by way of examples and with reference to the accompanying drawing.

represents a scissor lift according to a first preferred embodiment, its working platform being in the lowered position on its chassis.

represents the same lifting platform, but its working platform is this time in the raised position.

represents an isolated view of the control panel of this lifting platform which is equipped with a detection system comprising two immaterial barriers.

represents a local view of this lifting platform which shows one end of its working platform and the control console attached to its guardrail.

schematically represents a local perspective view of the working platform of this lifting platform with an operator standing at the control console.

schematically represents a top view for the case of the previous figure.

represents a block diagram of the assembly formed by the control panel, the operator protection system and the on-board electronics of the lifting platform according to the first embodiment.

represents an isolated view of another lifting platform control panel which is equipped with a detection system comprising three immaterial barriers.

represents a local view of this lifting platform which shows one end of its working platform and the control console of the previous figure attached to its guardrail.

is a view similar to the , and relates to an embodiment identical to the first embodiment described with reference to FIGS. 1 to 7, except for what concerns the detection system of the operator protection system.

represents, for this embodiment, a local perspective view of the working platform of this lifting platform with an operator standing at the control console.

schematically represents, for this embodiment, a top view on which is materialized the measurement beam of a LIDAR or LADAR detector equipping the detection system of the operator protection system and a normal positioning of the operator standing at the control console.

represents a lifting platform according to another embodiment which lifting platform is of the articulated type.

We will now describe the lifting platform according to the first preferred embodiment with reference to FIGS. 1 to 7. As can be seen in FIGS. 1 and 2, the lifting platform is a scissor lift. It comprises a chassis 1, a scissor lifting mechanism 2 mounted on the chassis 1 and a work platform 3 mounted on the scissor lifting mechanism 2. The work platform 3 is provided with a horizontal platform 7 surrounded by a guardrail 8 to prevent people from falling off it. The guardrail 8 comprises four sides 8a, 8b, 8c, 8d each corresponding to another side of the platform 7. The platform 7 and the guardrail 8 may comprise sliding parts at one end of the work platform 3 or at both ends in order to allow users to vary the work surface available on board the work platform 3.

The scissor lift mechanism 2 comprises beams hinged in the centre in a scissor manner, these scissor mechanisms being mounted one above the other by their ends which are pivotally connected in order to be able to extend. A hydraulic cylinder 4 – or alternatively several – is used to actuate the scissor lift mechanism 2 in order to lower and raise the work platform 3 to the desired working height.

The chassis 1 is provided with front wheels 5 and rear wheels 6 by means of which the chassis 1 rests on the ground and which allow the lifting platform to be translated on the ground. The front side of the lifting platform is referenced AV and its rear side is referenced AR. The lifting platform has a motorization to allow it to move autonomously on the ground. The motorization is generally mounted directly on the chassis 1.

Alternatively, the invention also relates to vertical mast lifting platforms. In vertical mast lifting platforms, the lifting mechanism is designed as an extendable mast comprising vertical parts sliding on each other to extend vertically to the desired working height. Their lifting mechanism sometimes comprises a turret on which the extendable mast is mounted, the turret being pivotally mounted on the chassis about a vertical axis in order to be able to vary the orientation of the working platform relative to the chassis. Sometimes, the working platform is mounted on the highest vertical part by means of a pendulum arm – i.e. an arm articulated to the vertical mast about a horizontal axis – in order to give the user more flexibility in reaching the working position.

More generally, the invention relates to any other type of lifting platform, regardless of the type of lifting mechanism of the platform, in particular telescopic or articulated lifting platforms. The invention is also applicable to the case of lifting platforms which are not motorized to ensure their autonomous movement on the ground, but which are towed or pushed for this purpose.

The work platform 3 is equipped with a control panel 10 illustrated in FIGS. 3 and 4. The control panel 10 is provided with control members allowing an operator to cause the work platform 3 to move to reach the desired working position. In this example, buttons 14 make it possible to select the type of movement that can be engaged with a control handle 13 from among the translation of the lifting platform on the ground and the vertical movement of the work platform 3. The control handle 13 makes it possible to execute the selected type of movement: it can be tilted forwards and backwards to, depending on the case, raise or lower the work platform 3 or move the lifting platform forwards or backwards on the ground. In other words, the operator initiates the desired movement by tilting the control handle 13. In normal operation, the initiated movement is executed as long as the control handle 13 is kept tilted and is stopped when the operator lets the control handle 13 return to its neutral position. The control handle 13 makes it possible to vary the speed of the selected movement according to its degree of inclination, preferably proportionally. Buttons - not shown - located on the top of the control handle 13 make it possible to modify the orientation of the steered wheels, in this case the front wheels 5 - alternatively, the rear wheels 6. The control panel 10 is provided with a wired connection, not shown - or alternatively a wireless connection - with on-board electronics 50 - cf. - housed for example under the chassis 1. The on-board electronics 50 controls the power components of the lifting platform, in particular the motorization and the hydraulic cylinder(s) 4, in particular depending on the commands entered by the operator at the control panel 10.

The control console 10 is removable and designed to be attached at different locations on the guardrail 8 for the convenience of the operator on board the work platform 3 when operating the lifting platform. For this purpose, the control console 10 has on its right side 21 a side plate 11 extending vertically relative to the housing of the control console 10. The plate 11 has at its upper end a suitable shape 12 – for example an upside-down U-shaped section – enabling the control console 10 to be attached to a horizontal bar of corresponding dimensions on the guardrail 8. The attachment system may be different and made in any suitable manner that enables the operator to manually unhook or attach the control console 10 to the guardrail 8 without requiring a tool. A manual locking system for the control console 10 on the guardrail 8 or a system for indexing the control console 10 on the guardrail 8 may also be provided, for example by means of a pin in order to prevent the control console 10 from sliding on the guardrail 8, for example under the effect of vibrations.

The control panel 10 is also designed to be able to be held with one hand so that the operator can operate the control elements 13, 14 with the other. This allows the operator to control the lifting platform from the ground. For this purpose, the control panel 10 is provided with a gripping handle 15, which in this example is designed as an opening in the side plate 11. In addition, the control panel 10 is sufficiently compact – preferably less than 30 cm wide, or even less than 25 cm – and has an appropriately low weight.

When on board the work platform 3, the operator manipulates the control members 13, 14 of the control console 10 when it is attached to the guardrail 8. The latter is then attached so as to be on the side of the guardrail 8 towards the inside of the work platform 3 in order to conveniently access the control members 13, 14. Most often, the operator attaches the control console 10 towards the front end of the long section 8b of the guardrail 8 as illustrated in FIGS. 1, 2 and 4.

Given the small width of the control console 10 and that its system for attaching to the guardrail 8 is arranged on the right side 21, the operator usually stands on the left side 22 of the control console 10 when manipulating the control members 13, 14, in this case with the right hand. This position is illustrated by the where the operator is referenced by the letter O, the operator also being symbolically represented on the The risk of crushing the operator then comes above all from an obstacle outside the lifting platform which hits him from behind when the lifting platform is moving backwards or which hits him from above when the work platform is being lifted 3.

However, the operator is also likely to approach the section 8b of the guardrail 8 and lean over this section, for example, to look at the orientation of the wheels of the lifting platform. The operator is even likely to position himself in front of the front side 20 of the control console 10, facing the section 8b of the guardrail 8 while manipulating the control members 13, 14 with his left hand and lean over the section 8b of the guardrail 8. The risk of crushing against this section 8b then comes primarily from an external obstacle above him if he initiates a movement to raise the work platform 3.

In order to ensure the safety of the operator, the control panel 10 is provided with an anti-crushing protection system for the operator when the latter is on board the work platform 3: this protection system is referenced 60 on the . The protection system 60 is provided to protect the operator against a risk of crushing due to an external obstacle – for example a part of a building or a structure or a tree branch – hitting him from behind or from above. It comprises a detection system 61 comprising two immaterial barriers visible in FIGS. 3 to 6.

A first light curtain B1 is erected in front of the part of the panel 8a of the guardrail 8 which is adjacent to the left side 22 of the control panel 10. A second light curtain B2 is erected above the part of the panel 8b of the guardrail 8 which is adjacent to the right side of the control panel 10 and which extends beyond the front side 20 of the control panel 10 in the direction towards the rear of the work platform 3. For more details on the implementation of the light curtains B1 and B2, reference may be made to WO 2017/178737.

In this embodiment, it is considered that there is a situation potentially presenting a risk of crushing for the operator as soon as interference with any one of the two immaterial barriers B1, B2 is detected. In the remainder of the description of this embodiment, the fact of mentioning that the detection system 61 detects a risky situation for the operator means that the detection system 61 detects interference with any one of the two immaterial barriers B1, B2. On the contrary, the fact of mentioning that the detection system 61 does not detect a risky situation for the operator means that the detection system 61 does not detect any interference with any one of the two immaterial barriers B1, B2.

As shown in the , the protection system 60 also comprises a management system 62 for the movement of the work platform 3. The detection system 61 is functionally connected to the management system 62 which is designed to manage the movement of the work platform 3 according to a detection signal provided to it by the detection system 61. For this purpose, the management system 62 may be constituted by its own electronic circuit which is interfaced with the on-board electronics 50 of the lifting platform. This electronic circuit may for example be housed in the control panel 10. Alternatively, the management system 62 may be fully implemented by the on-board electronics 50 of the lifting platform.

We will now describe how the protection system 60 manages the movements of the work platform 3 thanks to the management system 62 in cooperation with the detection system 61.

The management system 62 authorizes a normal operating mode in the absence of detection of a risk situation for the operator by the detection system 61, in other words in the absence of interference with one of the immaterial barriers B1, B2. In this case, the management system 62 authorizes the execution of the movements of the work platform 3 without any restriction. In other words, when the operator initiates any movement of the work platform 3 at the control panel 10, including by means of a translation of the lifting platform on the ground, the management system 62 authorizes its execution without restriction and the on-board electronics 50 therefore implements it at a normal speed of movement.

In the normal operating mode, the protection system 60 is preferably designed not to influence the ground translation of the lifting platform when the work platform 3 is in a fully lowered position because the operator is then in the situation of a simple driver of a motor vehicle. In other words, the ground translation of the lifting platform is authorized without taking into account the detection system 61 as soon as the work platform 3 is in a fully lowered position in accordance with the third rule stated above. In other words again, the first rule and the second rule are only implemented if the work platform 3 is at least partially raised.

Furthermore, in the normal operating mode, the protection system 60 is preferably designed not to influence the execution of a movement of the work platform 3 when the movement concerned is considered to be in itself without risk for the operator. Thus, the protection system 60 can be designed to always authorize the downward movement of the work platform 3 without taking into account the detection system 61. In other words, the downward movement of the platform is executed at its normal speed as long as this movement is engaged at the control panel 10 regardless of whether or not there is interference with one or other of the immaterial barriers B1, B2. Indeed, there is no risk of crushing the operator in the case of the downward movement of the work platform 3.

Similarly, the management system 62 can be designed to always allow the ground translation of the lifting platform in forward motion without taking into account the detection system 61. In other words, the ground translation of the lifting platform in forward motion is carried out at its normal speed as long as it is engaged at the control panel 10 regardless of whether or not there is interference with one or other of the immaterial barriers B1, B2. Indeed, in this case too, the risk of crushing for the operator remains low. This is all the more the case if the control panel is fixedly mounted on the work platform 3 towards the front thereof, unlike the case of the embodiment described, since in this case the operator at the control panel normally looks towards the front of the lifting platform.

Furthermore, it is advantageous that the management system 62 authorizes the change of orientation of the wheels independently of any possible detection of a risky situation for the operator by the detection system 61. Indeed, the change of orientation of the wheels does not cause any movement of the work platform 3 and therefore does not present any risk for the operator. And this allows the operator to lean over the guardrail 8 to see the orientation of the steered wheels 5 or 6 during the change of orientation of the wheels that he operates at the control panel 10.

In the normal operating mode, the protection system 60 is however designed to influence the execution of a movement of the work platform 3 in the event of detection of a risky situation for the operator when the movement concerned is considered to be risky for the operator. This is generally the case for the upward movement of the work platform 3. In the present embodiment, this is also the case for the translation on the ground of the lifting platform in reverse. These movements will be referred to below as risky movements.

Alternatively, it is nevertheless possible to treat the translational movement on the ground of the lifting platform in forward motion and/or the lowering movement of the working platform 3 as risky movements in the same way as the translational movement on the ground of the lifting platform in reverse motion and the raising movement of the working platform 3 and thus to influence their execution in a similar manner in the event of detection of a risky situation for the operator.

The way in which the management system 62 influences the execution of a risky movement of the work platform 3 initiated at the control panel 10 in the event of detection of a risky situation for the operator is different depending on the chronology between the moment when the movement of the work platform 3 is initiated at the control panel 10 and the moment when the detection system 61 detects the risky situation for the operator.

If a risky movement of the work platform 3 is in progress at the time when the detection system 61 detects the occurrence of a risky situation for the operator, the management system 62 causes the movement to stop in application of the first rule. This is the situation where the risky movement of the work platform 3 is initiated by the operator at the control panel 10 at a time when the detection system 61 does not detect a risky situation for the operator, but detects one subsequently while the risky movement of the work platform 3 is in progress: the first rule is then triggered. The management system 62 immediately causes the risky movement of the work platform 3 to stop as soon as the detection system 61 signals to it the existence of the risky situation for the operator.

In other words, in this embodiment, if during the normal operating mode, the operator engages at the control panel 10 the upward movement of the work platform 3 or the translation on the ground of the lifting platform in reverse at a time when there is no interference with one or other of the immaterial barriers B1, B2, but such interference occurs while one or other of these movements is being executed, the management system 62 immediately causes this movement to stop. On the other hand, as explained above, it is advantageous that the first rule does not apply to the downward movement of the work platform 3, nor to the translation on the ground of the lifting platform in forward motion.

When there is a triggering of the first rule, the management system 62 also immediately applies a first restricted operating mode in replacement of the normal operating mode. This first restricted operating mode is applied at least until a reset procedure is executed.

The risky movement that has been stopped by the management system 62 in application of the first rule remains prohibited for the entire time of application of the first restricted operating mode, including if the detection system 61 ceases to detect the risky situation. This prevents the risky movement from restarting automatically in the event of removal of the risky situation for the operator.

During the first restricted operating mode, the management system 62 also applies restrictions to the execution of other movements of the work platform 3 than that stopped by application of the first rule, if they are engaged at the control panel 3 after activation of the first restricted operating mode. The nature of the restriction differs again depending on whether the movement of the work platform 3 concerned is considered to be at risk or not for the operator. More precisely, depending on the movement concerned of the work platform 3, the management system 62 either prohibits its execution or authorizes it but only at a reduced speed compared to a normal speed of the movement.

Preferably prohibited during the first restricted operating mode is any movement of the work platform 3 considered to be at risk. In particular, it is preferable that the execution of the lifting movement of the work platform 3 is always prohibited, regardless of the current movement of the work platform 3 which has been stopped in application of the first rule.

On the other hand, any movement of the work platform 3 considered as potentially being able to reduce or eliminate the risk of crushing for the operator when a movement in progress of the work platform 3 has been stopped in application of the first rule is preferentially authorized at reduced speed during the first restricted operating mode. In this sense, if the current movement of the work platform 3 that has been stopped in application of the first rule is the upward movement, then the management system 62 preferentially authorizes the execution at reduced speed of the ground translation of the lifting platform in forward motion, the ground translation of the lifting platform in reverse motion and the downward movement of the work platform 3. If the current movement of the work platform 3 that has been stopped in application of the first rule is the ground translation of the lifting platform in reverse motion, then the management system 62 preferentially authorizes the execution at reduced speed of the ground translation of the lifting platform in forward motion and the downward movement of the work platform 3. On the other hand, the management system 62 prohibits the upward movement of the work platform 3 as mentioned above.

If during the normal operating mode, the detection system 61 detects a risky situation for the operator at the moment when the latter initiates a risky movement from the work platform 3 to the control panel 10, the second rule is triggered. In other words, the management system 62 authorizes the execution of this risky movement of the work platform 3 but only at a speed reduced compared to the normal speed of the movement. This is a case where the risky situation for the operator detected by the detection system 61 pre-exists or occurs simultaneously with the initiation of this movement from the work platform 3 to the control panel 10 by the operator.

In other words, in this embodiment, if during the normal operating mode, the operator initiates at the control panel 10 the upward movement of the work platform 3 or the translation on the ground of the lifting platform in reverse at a time when there is interference with one or other of the immaterial barriers B1, B2, the management system 62 authorizes the execution of this movement but only at the reduced speed. On the other hand, as explained above, it is preferable that the second rule does not apply with respect to the downward movement of the work platform 3, nor with respect to the translation on the ground of the lifting platform in forward motion.

The risky movement of the work platform 3 engaged at the control panel 10 under the conditions of the second rule is preferably executed at the reduced speed as long as it remains engaged at the control panel 10, including if the detection system ceases to detect the risky situation for the operator. This avoids possible variations in the speed of the movement which could destabilize the operator.

It is even more preferable to exclude the application of the first rule when a movement is in progress at reduced speed and to have the movement of the work platform 3 executed at reduced speed in application of the second rule as long as it remains engaged at the control panel without taking into account the detection system. Productivity is thus improved by avoiding stoppages of movement of the work platform 3 which would be due to the application of the first rule. The safety of the operator is nevertheless sufficiently ensured due to the reduced speed of the movement which allows him to react in the event of danger.

Even more advantageously, it can be provided that as soon as there is a triggering of the second rule, the management system 62 immediately applies a second restricted operating mode in replacement of the normal operating mode. This second restricted operating mode is applied until a reset procedure is executed. The management system 62 preferably authorizes the execution of any movement of the work platform 3 that the operator initiates at the control panel 10 during the second restricted operating mode, but only at a speed reduced compared to a normal speed of movement. In other words, no movement of the work platform 3 is executed at the normal operating speed during the second restricted operating mode. It is even more advantageous that the management system 62 does not apply the first rule during the second restricted operating mode and authorizes the execution of any movement of the work platform 3 at the reduced speed without taking into account the detection system 61. Thus, the protection system 60 will not cause any stoppages of the movements of the work platform 3 during the second restricted operating mode. These measures all go in the direction of a gain in productivity while satisfactorily ensuring the safety of the operator due to the reduced speed of the movements of the work platform 3 during the second restricted operating mode.

In this embodiment, the operation of the control handle 13 during the application of the first restricted operating mode and during the application of the second restricted operating mode is preferably similar to the normal operating mode. In other words, any movement of the work platform 3 permitted only at a reduced speed in the first restricted operating mode or in the second restricted operating mode, which is engaged at the control handle 13 is executed as long as the control handle 13 is kept inclined and it is stopped when the operator lets the control handle 13 return to its neutral position. And the speed of the selected movement also varies depending on the degree of inclination of the control handle 13 preferably proportionally. Simply, the maximum value of the speed of the movement concerned is reduced during the application of one or the other of the restricted operating modes compared to the maximum value of the speed of this movement during the normal operating mode. This prevents the operator from being disturbed by a different operation of the control handle 13 when the restricted operating modes are applied.

Whether during the first restricted operating mode or during the second restricted operating mode, it is preferable that the maximum value of the reduced speed of a movement of the work platform 3 is less than or equal to half the maximum value of the normal speed of this same movement and is more preferably still less than or equal to a quarter or even a fifth of the latter.

As mentioned, the first restricted operating mode and the second restricted operating mode can be deactivated to return to the normal operating mode by means of a reset procedure. At least one reset procedure is provided that can be carried out at the control panel 10 by the operator, which avoids the need for a third party to intervene. This reset procedure is preferably the same for both restricted operating modes. It is preferable to deactivate each of the restricted operating modes by executing the reset procedure only on condition that the detection system 61 has ceased to detect a risky situation for the operator, which allows a particularly safe transition to the normal operating mode for the operator.

For example, the reset procedure consists of disengaging any movement of the work platform 3 at the control panel 10. In other words, in this embodiment, the operator must allow the control handle 13 to return to the neutral position. In addition, the operator O must reposition himself so as to no longer interfere with the immaterial barriers B1 and B2 in order to deactivate the current restricted operating mode and reactivate the normal operating mode. In other words, when these two conditions are satisfied simultaneously, the operator O can restart the movement concerned by re-engaging it at the control panel 10 or else initiate another movement of the work platform 3 at the control panel 10, the movement then being executed at its normal speed in accordance with the normal operating mode. The simplicity of this reset procedure has the advantage of promoting productivity while promoting a safe transition to normal operating mode since no movement is initiated at the control panel 10 at the time of transition to normal operating mode.

Alternatively, the reset procedure may additionally include pressing a reset button on the control panel 10.

Optionally, a push button 40 - or another type of manually actuated member - may be arranged on the control panel 10 to allow the operator to neutralize the protection system 60, in other words to prevent the protection system 60 from stopping the movements of the work platform 3, including by translation on the ground of the lifting platform, or from reducing its speed. This makes it possible to avoid untimely triggering of the protection system 60 when the control panel 10 is not attached to the guardrail 8, but the operator is holding the control panel 10 by hand. It is preferable for the neutralization to be effective only as long as the operator keeps the push button 40 or the member concerned actuated. Furthermore, it is preferable for the operator to be informed of the neutralization of the protection system 60 by some signal on the control panel 10 or otherwise. It is preferable to provide such a neutralizing organ of the protection system 60 only for removable type control desks which are intended to be used with one hand by the operator while he holds it with his other hand.

Figures 8 and 9 illustrate a second preferred embodiment using another control console – referenced 100 – provided with manual control members 113, 114 similar to those of the control console 10. The elements corresponding to those of the control console 10 are referenced by the same numbers increased by 100.

The entire description given for the first preferred embodiment is applicable for this second preferred embodiment, except for the differences discussed below.

The control console 100 is also removable and designed to be hung at different locations on the guardrail 8 by the operator without using tools. But in this case, its hanging system 112 is placed on the rear side 123 of the control console 100. The control console 100 has a size and weight greater than those of the control console 10 and is not designed to be held with one hand while manipulating the control members 113, 114 with the other hand.

The control panel 100 comprises an operator protection system comprising a detection system with two light curtains B101, B102 which respectively provide the same function as the light curtains B1, B2 of the control panel 10. It will be noted that the photoelectric detector D102 of the light curtain B102 is housed laterally in the lower part of the front side of the control panel 100. The photoelectric detector D101 of the light curtain B101 is housed in a support 130 which advances relative to a rear plate 111 for mounting on the guardrail 8. This makes it possible to place the light curtain B101 at the appropriate distance from the panel 8a of the guardrail 8.

Finally, because the control panel 100 is wider than the control panel 10, it is desirable to protect the operator from the risk of being crushed against the control panel 100. For this purpose, the detection system comprises a third immaterial barrier B103. The light curtain B103 extends above the control panel 100 preferably from the rear 123 thereof so that the operator does not interfere with the light curtain 103 when standing upright at the control panel 100, but on the contrary interferes with it when leaning beyond a certain angle on the control panel 100. For this, it is advantageous for the light curtain B103 to extend from the rear 123 of the control panel 100 while being oriented upwards towards the front 120 of the control panel 100 as illustrated. For more details on the implementation of the light curtains B101, B102 and B103, reference may be made to WO 2017/178737.

In this second embodiment, a protection system similar to the protection system 60 of the first embodiment is provided: its management system implements the same management of the movements of the work platform as the management system 62 of the first embodiment. The only difference is that a situation with a risk of crushing for the operator O is determined this time by the detection of interference with any of the immaterial barriers B101, B102 and B103.

It is preferable that the maximum detection distance of the light curtains B101, B102 and B103 as well as that of the light curtains B1, B2 of the first embodiment is appropriately limited in order to avoid untimely triggering of the protection system when the working environment at height is cluttered. From this point of view, it is preferable that the maximum detection distance of each of the light curtains, measured from the control panel 10, 100 is less than or equal to 100 cm and more preferably less than or equal to 60 cm. This maximum detection distance is referenced respectively l1 and l2 for the light curtains B1 and B2 of the control panel 10 – cf. - and it is referenced respectively l101, l102 and l103 for the immaterial barriers B101, B102 and B103 of the control panel 100.

Figures 10 to 12 illustrate a third preferred embodiment which is based on the first embodiment described with reference to Figures 1 to 7. The only differences of this third embodiment compared to the first embodiment reside in the detection system of the operator protection system 60. Consequently, all the description given for the first embodiment applies to this third embodiment and the same reference numbers are used to designate the same elements, except for what concerns the detection system – hereinafter referenced 61’ – and its components. The detection system 61’ is operatively connected to the management system 62 as in the first embodiment. The detection system 61’ is based on one or more LIDAR or LADAR sensors. It will now be described in more detail.

The detection system 61’ comprises a first LIDAR or LADAR sensor referenced D201. The sensor D201 is arranged on the control console 10 so as to point towards the front of the control console 10 in the direction of the place where the operator O normally stands in front of the control console 10 when he uses it to control the movements of the work platform 3. The measuring beam of the sensor D201 is symbolized by dashes and is referenced F1. The sensor D201 therefore makes it possible to measure the distance between the operator O and the control console 10 when he stands in front of the control console 10.

As illustrated in the , the sensor D201 makes it possible to define a protected driving zone referenced Z2 in which the operator O is supposed to stand when using the control panel 10. The protected driving zone Z2 corresponds to a distance interval defined relative to the sensor D201. The protected driving zone Z2 is defined as extending from a distance L1 to a distance L2 greater than L1, both being defined relative to the sensor D201. This distance interval is defined so as to correspond to a position of the operator O relative to the control panel 10 which is neither too close nor too far from it.

In operation, it is considered that there is potentially a risk situation for operator O when the distance of operator O measured by sensor D201 is outside this distance interval. This is the case if operator O is in a zone Z1 corresponding to a distance less than distance L1 from sensor D201. This is also the case if operator O is in a zone Z3 corresponding to a distance greater than distance L2 from sensor D201.

It is also considered that there is potentially a risk situation for operator O in the event that sensor D201 does not report a distance measurement because operator O is standing outside the measurement beam F1 or beyond the measurement range of sensor D201, which in this case is a distance L3 greater than L2.

In summary, it is considered that, during operation, there is potentially a risk situation when the detection system 61’ determines by means of the sensor D201 that the operator O is outside the zone Z2.

The detection system 61’ can be supplemented by a second LIDAR or LADAR sensor referenced D202. Its measuring beam is referenced F2 in FIGS. 10 and 11. The sensor D202 is dedicated to detecting a risk of crushing of the operator O against the section 8b of the guardrail 8 located next to the control panel 10 when it is attached to the dedicated location of the guardrail 8. The second sensor D202 is useful due to the small size of the control panel 10. Indeed, it is possible that the detection system 61’ determines that the operator O is in the distance interval relative to the first sensor D201 which corresponds to the zone Z2 while he can simultaneously be leaning towards the section 8b, which potentially corresponds to a situation with a risk of crushing for the operator O.

The sensor D202 is arranged on the control console 10 such that, on the one hand, its measuring beam F2 does not encounter the operator O when he is normally standing at the control console 10, i.e. without leaning towards the section 8b of the guardrail 8. And on the other hand, the sensor D202 is arranged on the control console 10 such that its measuring beam F2 encounters the operator O when he is leaning towards the section 8b while he is located in the distance interval relative to the first sensor D201 which corresponds to the zone Z2. As can be seen in FIGS. 11 and 12, it is arranged on the lateral side of the control console 10 which is close to the section 8b. The measuring range of the sensor D202 may be more limited than that of the sensor D201.

Therefore, it is considered that there is potentially a risk situation for operator O since sensor D202 provides a distance measurement because operator O cuts the measuring beam F2.

The D202 sensor thus makes it possible to laterally delimit the protected driving zone Z2 on the side corresponding to section 8b of the guardrail 8.

It will be understood that the sensor D202 provides the same protection function as the light curtain B2 of the first embodiment. Alternatively, the sensor D202 is replaced by the light curtain B2 of the first embodiment.

In summary, in this third embodiment, the detection system 61’ detects a potentially risky situation for the operator O as soon as it determines by means of the sensors D201 and D202 that the operator O is located outside the protected driving zone Z2. In cooperation with the detection system 61’, the management system 62 of the operator protection system implements the same management of the movements of the work platform 3 as that which was described above for the first embodiment.

There represents a self-propelled lifting platform according to another embodiment which lifting platform is of the articulated type. It comprises a chassis 301 supporting a lifting device 302 of a work platform 303. The lifting device 302 comprises in a known manner two articulated arms supporting at its upper end a telescopic arm at the end of which is supported the work platform 303 possibly by means of a small pendulum arm. The lifting device 302 is mounted on the chassis 301 by means of a turret 304. The turret 304 can rotate about a vertical axis relative to the chassis 301, which makes it possible to modify the angular orientation of the lifting device 302 relative to the chassis.

A control console 300 is fixedly mounted on or near the guardrail of the work platform 303. The control console 300 allows an operator to initiate the various movements of the work platform 303, including the translation on the ground of the chassis 301. It therefore allows the lifting platform to be translated on the ground in forward and reverse gear, to raise or lower the work platform 303 and to rotate the turret 304 relative to the chassis 301.

The control panel 300 is equipped with a system for protecting the operator on board the lifting platform which operates in a similar manner to those described so far. In other words, it comprises a detection system for detecting a risky situation for the operator on board the work platform 303. The detection system may be similar to one or other of the embodiments described above.

The detection system is functionally connected to a management system which manages the movements of the work platform 303 in particular on the basis of the detection signal provided by the detection system.

The management system implements a management of the movements of the work platform 303 similar to that described for the embodiments described above, but by additionally managing the rotational movement of the turret 304. From this point of view, the rotational movement of the turret 304 is considered to be a risky movement in both directions of rotation. In other words, the first rule is also implemented with respect to the rotation of the turret 304, that is to say to stop its rotation if it is in progress at the time when a risky situation for the operator is detected. In this case, the first restricted operating mode will authorize the rotation of the turret 304 at a reduced speed in the opposite direction compared to the direction of rotation that was stopped in application of the first rule. In the event of triggering of the second rule, the rotation of the turret 304 will also be authorized but only at a reduced speed compared to the normal rotation speed, regardless of the direction of rotation. The first restricted operating mode and the second restricted operating mode described for the other embodiments can be applied similarly, considering that the rotational movement of the turret 304 is a risky movement in both directions of rotation.

Of course, the present invention is not limited to the examples and the embodiment described and shown, but it is susceptible to numerous variants accessible to those skilled in the art.

Claims (22)

Method for protecting an operator (O) from being crushed on board a work platform (3; 303) of a lifting platform, which method is implemented automatically, the lifting platform comprising a control panel (10; 100; 300) intended to be used on board the work platform and designed to allow the operator to initiate a movement of the work platform, the lifting platform further comprising a detection system (61; 61') for detecting a risky situation for the operator (O) on board the work platform and the protection method comprising:

• the implementation of a first rule according to which the movement of the work platform is stopped if the movement is in progress at the time when the detection system (61; 61') detects the occurrence of the risk situation for the operator (O), and
• the implementation of a second rule according to which the movement of the work platform is carried out at a reduced speed compared to a normal speed of movement if the risk situation for the operator (O) is detected by the detection system at the time of engagement of the movement at the control desk (10).

The method of claim 1, which comprises:

• after triggering of the second rule, the execution of the movement of the work platform at the reduced speed as long as the movement remains engaged at the control panel (10; 100; 300), including if the detection system (61; 61') ceases to detect the risk situation for the operator (O).

The method of claim 1 or 2, wherein the method comprises:

• the exclusion of the application of the first rule when the movement is in progress at reduced speed, and
• after triggering of the second rule, execution of the movement at reduced speed as long as the movement remains engaged at the control desk (10; 100; 300) without taking into account the detection system.

A method according to any one of claims 1 to 3, wherein the control console (10; 100; 300) is designed to enable the operator to initiate a lifting movement of the work platform, the method comprising:

• the implementation of the first rule according to which the upward movement of the work platform is stopped if the upward movement of the work platform is in progress at the time when the detection system (61; 61') detects the occurrence of the risk situation for the operator (O), and
• the implementation of the second rule according to which the upward movement of the work platform is carried out at a reduced speed compared to a normal speed of movement if the risk situation for the operator (O) is detected by the detection system at the time of engagement of the upward movement of the work platform at the control panel (10).

Method according to any one of claims 1 to 4, in which the lifting platform is self-propelled so as to be able to translate on the ground, the control console (10; 100; 300) being designed to allow the operator to initiate a translation on the ground of the lifting platform, the method comprising:

• the implementation of the first rule according to which the ground translation of the lifting platform is stopped if the ground translation of the lifting platform is in progress at the time when the detection system (61) detects the occurrence of the risk situation for the operator (O), and
• the implementation of the second rule according to which the ground translation of the lifting platform is carried out at a reduced speed compared to a normal ground translation speed of the lifting platform if the risk situation for the operator (O) is detected by the detection system at the time of engagement of the ground translation of the lifting platform at the control console (10).

A method according to claim 5, comprising:

• the implementation of the first rule and the second rule only if the working platform is at least partially lifted, and
• the implementation of a third rule according to which the ground translation of the lifting platform is authorized without taking into account the detection system on condition that the work platform is in a fully lowered position.

A method according to any one of claims 1 to 6, wherein the control console (10; 100; 300) is adapted to allow the operator to selectively engage any one of a plurality of different movements of the work platform, the method comprising:

• the exclusion of at least one movement of the working platform from the implementation of the first rule and the second rule so as to authorize this movement of the working platform without taking into account the detection system.

A method according to claim 7, wherein the control console (10; 100; 300) is designed to enable the operator to initiate a downward movement of the work platform, the method comprising:

• the exclusion of the downward movement of the working platform from the implementation of the first rule and the second rule so as to allow the downward movement of the working platform without taking into account the detection system.

Method according to claim 7 or 8, in which the control console (10; 100; 300) is designed to allow the operator to initiate a ground translation of the lifting platform in forward motion, the method comprising:

• the exclusion of the ground translation of the lifting platform in forward motion from the implementation of the first rule and the second rule so as to authorize the ground translation of the lifting platform in forward motion without taking into account the detection system.

A method according to any one of claims 1 to 9, wherein at least one reset procedure is provided, the reset procedure being executable at the control console, the method comprising:

• if the first rule is triggered, the application of a first restricted operating mode until the reset procedure is performed, and
• the prohibition of movement during the entire time of application of the first restricted operating mode.

A method according to claim 10, wherein the control console (10; 100; 300) is adapted to allow the operator to selectively engage any one of a plurality of different movements of the work platform, the method comprising for each of the movements of the work platform:

• either the prohibition on carrying out the movement of the work platform during the entire time of application of the first restricted operating mode,
• or the authorization to execute the movement of the work platform only at a speed reduced compared to a normal speed of movement during the entire time of application of the first restricted operating mode.

A method according to claim 10, wherein the control console (10; 100; 300) is adapted to allow the operator to selectively engage any one of a plurality of different movements of the work platform, the method comprising for each of the movements of the work platform:

• either the prohibition on carrying out the movement of the work platform during the entire time of application of the first restricted operating mode,
• or the authorization to execute the movement of the work platform only at a speed reduced compared to a normal speed of movement without taking into account the detection system during the entire time of application of the first restricted operating mode.

A method according to claim 11 or 12, wherein the control console (10; 100; 300) is adapted to enable the operator to initiate a lifting movement of the work platform, the method comprising:

• the prohibition of the upward movement of the working platform during the entire time of application of the first restricted operating mode, regardless of the movement of the working platform which was in progress at the time of triggering of the first rule.

Method according to any one of claims 11 to 13, in which the lifting platform is self-propelled so as to be able to translate on the ground and the control console (10; 100) is designed to allow the operator to selectively engage a translation on the ground of the lifting platform in forward motion, a translation on the ground of the lifting platform in reverse motion, a raising movement of the work platform and a lowering movement of the work platform, the method comprising during the application of the first restricted operating mode due to a triggering of the first rule at a time when the work platform was subjected only to a raising movement:

• the authorization to perform only at a speed reduced compared to a normal speed of movement any movement among the translation on the ground of the lifting platform in forward motion, the translation on the ground of the lifting platform in reverse motion and the lowering movement of the work platform.

Method according to any one of claims 11 to 14, in which the lifting platform is self-propelled so as to be able to translate on the ground and the control console (10; 100; 300) is designed to allow the operator to selectively engage a translation on the ground of the lifting platform in forward gear, a translation on the ground of the lifting platform in reverse gear, a raising movement of the work platform and a lowering movement of the work platform, the method comprising during the application of the first restricted operating mode due to a triggering of the first rule at a time when the work platform was subjected only to a translation on the ground of the lifting platform in reverse gear:

• authorization to perform only at a reduced speed compared to a normal speed of movement the translation on the ground of the lifting platform in forward motion and the lowering movement of the working platform.

A method according to any one of claims 1 to 15, wherein the control console (10; 100; 300) is adapted to allow the operator to selectively engage any one of a plurality of different movements of the work platform and at least one reset procedure is provided, the reset procedure being executable at the control console, the method comprising:

• if the second rule is triggered, the application of a second restricted operating mode until the reset procedure is performed, and
• during the entire time of application of the second restricted operating mode, authorization to perform any movement of the work platform only at a speed reduced compared to a normal speed of movement.

Method according to claim 16, in which the method comprises during the entire time of application of the second operating mode:

• the exclusion of the application of the first rule and the authorization to perform any movement of the work platform at reduced speed without taking into account the detection system.

A method according to any one of claims 10 to 17, comprising:

• when the first restricted operating mode is being applied, deactivation of the first restricted operating mode in the event of execution of the reset procedure provided that the detection system (61; 61') has ceased to detect a situation which poses a risk to the operator (O), and/or:
• when the second restricted operating mode is being applied, deactivating the second restricted operating mode in the event of execution of the reset procedure provided that the detection system (61; 61') has ceased to detect a risk situation for the operator (O).

A method according to any one of claims 10 to 18, wherein the reset procedure comprises or consists of disengaging any movement of the work platform at the control console, the method comprising deactivating the first restricted operating mode and/or the second operating mode upon execution of the reset procedure provided that any movement of the work platform is disengaged at the control console and the detection system (61; 61') has ceased to detect the risk situation for the operator (O). A method according to any one of claims 1 to 19, wherein the lifting platform comprises a turret (304) pivotally mounted on a chassis (301), the turret supporting a lifting device (302) of the work platform (303), the control console (300) being designed to allow the operator to initiate rotation of the turret (304), the method comprising:

• implementing the first rule which includes stopping the rotation of the turret (304) if the rotation of the turret is in progress at the time when the detection system (61) detects the occurrence of the risk situation for the operator (O), and
• implementing the second rule which includes rotating the turret (304) at a reduced speed compared to a normal turret rotation speed if the risk situation for the operator (O) is detected by the detection system at the time when the turret rotation is engaged at the control console (10).

Anti-crushing protection system (60) for an operator (O) of a lifting platform comprising a work platform (3; 303) and a control panel (10; 100; 300) intended to be used on board the work platform and designed to allow the operator to initiate at least one movement of the work platform (3), the protection system comprising:

• a detection system (61; 61') for detecting a risky situation for the operator (O) on board the work platform; and
• a management system (62) for the movement of the work platform, which management system is functionally connected to the detection system,

wherein the management system (62) is configured to implement the method according to any one of claims 1 to 20. Lifting platform, comprising a work platform (3; 303) movable at least in height and a control panel (10; 100; 300) intended to be used on board the work platform (3; 303) and designed to allow an operator (O) to initiate at least one upward movement of the work platform and one downward movement of the work platform, the lifting platform further comprising a protection system according to claim 21, and preferably:

• the lifting platform is self-propelled to translate on the ground in forward and reverse gear, in which case the control panel (10; 100; 300) is further designed to allow the operator to initiate a translation on the ground of the lifting platform in forward and reverse gear, and/or
• the lifting platform:
  • either is a scissor lift or a fixed vertical mast lift,
  • either comprises a turret (304) pivotally mounted on a chassis (301) in which case the turret supports a lifting device (302) of the work platform (303) and the control console (300) is further designed to allow the operator to initiate rotation of the turret (304), the lifting platform preferably being a lifting platform with a telescopic mast or a lifting platform with an articulated mast or a lifting platform with a vertical mast and pivoting turret.