Control system for a working crane to reduce the environmental impact of variable speed drives.

Abstract

Control system (1) for operating a crane (100; 200), comprising at least: - a control interface (2); - a control system (3) connected to the control interface; - working actuators (6; 61, 62) ensuring the movement of the load; - variable speed drives (4; 41) connected to the control system and to the working actuators to receive control commands (DO1; DO2) from the control system and transmit speed instructions (S6; S61; S62) to the working actuators; with at least one of the speed controllers (4; 41), called the common controller (41), connected to at least two of the working actuators, called the shared actuators (61, 62), by means of a distribution relay (51), so that the common controller alternately drives each of the shared actuators. (See diagram: Figure 3)

Description

Title of the invention: System for controlling a crane at work to reduce the environmental impact of variable speed drives. Technical field

[0001] The invention relates to a system for controlling a crane.

[0002] It relates more particularly to a system for controlling a crane at work which is part of an eco-design approach, for which the use of electric actuators and speed variators implementing the various movements of the crane is as energy-efficient and polluting as possible.

[0003] The invention also relates to a crane comprising the aforementioned control system.

[0004] The invention also relates to a control method implemented by working control of a crane.

[0005] The invention finds a preferred, and non-limiting, application for a plurality of types of crane, for example: cranes with element assembly, automated assembly cranes, luffing jib cranes, mobile cranes in translation on a rail. Prior art

[0006] In a known manner, the loads are lifted and moved by the cranes by means of electric working actuators controlled by the crane operator from a control interface present in the control cabin or on a radio control or any remote control station; such a control interface may be in the form of a control joystick and / or buttons.

[0007] In the field of cranes, the working actuators conventionally comprise a lifting winch which is used to vertically raise and lower the load; a distribution winch which is used to distribute the load along a distributing boom, by moving a distributing trolley; a slewing actuator which is used to orient a boom around a vertical axis; a lifting actuator which is used to angularly raise or lower a boom for a luffing jib crane; a translation actuator which is used to translate the crane on a rail for a mobile crane in translation; etc.

[0008] For each type of load movement (lifting, distribution, orientation, raising, translation, etc.), an electric actuator, hereinafter called a working actuator, is necessary for its realization.

[0009] Commonly, the at least one working actuator implementing a movement among the several movements that the crane can perform is connected to a variable speed drive. speed (also called variable frequency drive) designed to regulate the speed of the electric motor of the working actuator for the purposes of motion control, energy consumption management, reduction of mechanical stress on motor control applications, etc. The variable speed drive is also connected to the crane's control system, which is in turn connected to the control interface. Thus, when the crane operator uses the control interface to implement a movement at a given speed, it generates control signals that are sent to the control system, which will translate them into control commands. These control commands are then sent to the variable speed drives by the control system. Based on these, the variable speed drive transmits speed instructions to the at least one working actuator so that it performs the movement at the desired speed.

[0010] Thus, each crane movement is associated with a speed variator. The speed variators, and by extension the movements, are therefore independent in terms of control of each other. Generally, the operation of the cranes is designed so that the crane operator can simultaneously carry out all the movements, as long as this simultaneity is possible and / or authorized. Lifting, orientation and distribution movements can, for example, be prohibited during a translation.

[0011] However, companies today must positively comply with new regulations to initiate their ecological transition and put into practice behaviors in favor of sustainable development, with the aim of providing a global and lasting solution to the major environmental challenges of this century. The ecological transition aims to establish a model of economic, social, resilient and sustainable development that positively rethinks the way we consume, produce, work and live together, particularly in the areas of reducing energy consumption and polluting emissions.

[0012] Variable speed drives are electrical / electronic systems comprising power electronics, control electronics, mechanical components for cooling, motors, electromechanical components, etc. However, some of the components or subsystems included in variable speed drives require rare and / or highly polluting materials for their manufacture, which materials can also be treated or shaped using compounds that are also polluting or subject to ecological controversy. For example, additives such as flame retardants are introduced into certain materials used, which are also suspected of being harmful to health. Furthermore, the components of variable speed drives are generally rarely reconditioned / recycled, and are difficult to repair in the event of malfunction or breakdown.

[0013] This is why the use of a plurality of speed variators in the func- The operation of a crane tends to become incompatible with increasingly drastic environmental regulations, and with a desire to reduce the ecological impact of cranes widely used in the construction field. Summary of the invention

[0014] The invention proposes to respond to the problem set out above by providing a control solution for implementing the movements of a crane which is more ecological, in particular being less energy-consuming and polluting, and ecological than the usual control solutions; this for comparable operating performances.

[0015] The invention relates to a control system for controlling a crane during operation, comprising at least: - a control interface to allow a crane operator to control movements of a load by the crane; - a control-command system connected to the control interface to receive control signals from the control interface and generate control orders based on said control signals; - working actuators ensuring the load displacement movements; - variable speed drives which are connected to the control system and to the working actuators to receive control commands from the control system and transmit speed instructions to the working actuators according to the control commands.

[0016] This control system is remarkable in that at least one of the speed variators, called the common variator, is connected to at least two working actuators, called shared actuators, among the working actuators, via a distribution relay, said distribution relay being controlled to alternately connect the common variator with each of the at least two shared actuators, so that the at least two shared actuators operate alternately.

[0017] In other words, the invention proposes to associate two distinct displacement movements that a crane can perform when it is working, and therefore to associate the two working actuators each responsible for one of the two movements, with a single speed variator. As indicated above, the working actuators responsible for the two displacement movements are designated as being shared actuators, and the speed variator connected to these two shared actuators is designated as being a common variator.

[0018] The connection to the common variator for the two shared actuators implies that the two displacement movements cannot be carried out simultaneously but alternately. This alternation is ensured in particular by the distribution relay. Therefore, the crane operator must complete one of two movements if he wishes to initiate the other of the two movements.

[0019] In one embodiment of the invention, following the end of the first movement of movement (which is detected by crane equipment such as sensors, and / or by the control-command system), the crane operator will have to wait a short predefined delay (of a few seconds for example) to initiate the second movement of movement. In order for the crane operator to be warned that the delay has elapsed, it is conceivable for the control interface to warn him by means of a text message or a visual indication displayed on a screen, and / or an audible signal.

[0020] In a second embodiment of the invention, the distribution relay is controlled by the control-command system. Depending on the control signal received by the control-command system, and which is representative of one of the two movement movements that the crane operator wishes to perform, the distribution relay connects the output of the common variator to the input of the shared actuator in charge of said movement movement; so that the common variator provides it with the power necessary to carry out the movement movement at the desired speed. Thus, the common variator is not electrically connected via the distribution relay to the shared actuator in charge of the other of the two movements.

[0021] In a third embodiment of the invention, in the context of an application where the speeds of the two displacement movements must be rigorously precise, speed measuring devices present on the crane, such as sensors, are configured to measure said speeds during the performance of the two displacement movements, then to transmit the measured speeds to the common variator. The common variator then compares the measured speed values ​​with the speed setpoints contained in the control order; providing, depending on whether the measured speeds are lower (respectively higher) than the speed setpoints, more (respectively less) power to the shared actuators.In an alternative embodiment of the invention, the common drive, once the speed measurements have been received, transmits them to the control-command system which will compare them with the control signals sent by the control interface. Depending on the comparison results, the control-command system adapts or not the control order transmitted to the common drive for the control of the shared actuators. In another alternative embodiment of the invention, it is possible to envisage that the speeds measured by the sensors are transmitted directly to the control-command system.

[0022] In a fourth embodiment of the invention, in order to regulate the speed of a displacement movement, it is possible for the crane to be equipped of at least one brake associated with at least one of the working actuators, which brake is controlled in two variant embodiments of the invention either by a speed variator or by the control-command system. It is also conceivable that the brake communicates its state (brake open or brake closed) to the speed variator or to the control-command system.

[0023] The first advantage of the proposed solution is that it fits positively into an eco-design logic in favor of sustainable development.

[0024] By using a single variable speed drive instead of two for implementing two movements of a working crane, this means that it is only necessary to manufacture a single variable speed drive. For the manufacturers of the variable speed drive, this amounts to reducing by half the number of resources used during the manufacturing stage, whether it is a component that can be difficult to recondition and / or recycle; materials that can be rare and polluting, dangerous additives, etc.

[0025] The invention is also less energy-intensive since only one speed variator needs to be powered to operate.

[0026] It is also possible to equip the crane with several common variators, as long as it is possible, depending on the type of crane, to group together two travel movements. Two movements which are generally never carried out in parallel, but successively, can be grouped together. For example, lifting, orientation, or distribution movements are generally prohibited during a translation movement.

[0027] Thus, and advantageously, the proposed invention makes it possible to reduce the environmental impact of speed variators, and by extension of the crane, on several scales, whether it concerns: the application context itself on the construction site; or even the circulation and exploitation of non-recyclable, and / or polluting, and / or potentially dangerous resources for health.

[0028] The second advantage of the invention is economic since by reducing the number of speed variators, the manufacturing cost of a crane decreases (this reduction may possibly be reflected in the purchase price of the crane).

[0029] Finally, a final advantage of the invention is that the removal of a speed variator to associate two actuators with a common variator does not lead to a degradation of the operating performance of the crane in terms of load movement; since, as indicated previously, the two movement movements which are grouped correspond to movements generally carried out successively.

[0030] According to a characteristic of the invention, the distribution relay is controlled by the common variator which is configured to send to said distribution relay distribution instructions based on pilot orders from the control-command system.

[0031] In other words, the switching of the distribution relay to connect the common variator to one or the other of the two shared actuators is controlled by the common variator itself. Depending on the control order it receives, the common variator sends a distribution instruction to the repair relay so that it switches from one shared actuator to the other, or so that it remains in its current switching configuration.

[0032] According to a characteristic of the invention, the control-command system is configured to transmit to the control interface an alert message intended for the crane operator when said crane operator acts on the control interface in order to simultaneously control two movements associated with shared actuators which can only operate alternately.

[0033] In other words, in the case where the crane operator attempts to implement the two displacement movements associated with the updated actuators, the control interface displays an error message sent by the control-command system and the crane operator's action is neutralized, that is to say that neither of the two movements is initiated during his attempt.

[0034] In the embodiment of the invention where a delay is provided between the end of the execution of the first movement of movement and the initiation of the second movement of movement, the control-command system emits an error message in the case where the crane operator attempts to initiate the second movement during this delay. Thus, a tapping by the crane operator, that is to say a piloting by impulse alternately on the controls piloting the two movements of movement, is automatically detected then neutralized.

[0035] According to a characteristic of the invention, the working actuators comprise a lifting actuator associated with a lifting movement, an orientation actuator associated with an orientation movement and a distribution actuator associated with a distribution movement for the crane which is of the distributing jib crane type, and the at least two shared actuators comprise the lifting actuator and the orientation actuator in a first configuration, or the at least two shared actuators comprise the lifting actuator and the distribution actuator in a second configuration.

[0036] According to a characteristic of the invention, the distribution actuator is connected to another speed variator, among the speed variators, distinct from the common variator in the first configuration, or the orientation actuator is connected to another speed variator, among the speed variators, distinct from the common variator in the second configuration.

[0037] According to a characteristic of the invention, the control system is such that:

[0038] - in the first configuration: the other speed variator, called other variator common, is connected to a translation actuator associated with a translation movement and to the distribution actuator via another distribution relay, said other distribution relay being controlled to alternately connect the other common variator with the translation actuator and the distribution actuator, so that the translation actuator and the distribution actuator operate alternately; or - in the second configuration: the other speed variator, called the other common variator, is connected to a translation actuator associated with a translation movement and to the orientation actuator via another distribution relay, said other distribution relay being controlled to alternately connect the other common variator with the translation actuator and the orientation actuator, so that the translation actuator and the orientation actuator operate alternately.

[0039] The two displacement movements attached to the common variator are ergonomically chosen to maintain, or at least to approach, following the removal of a speed variator attached to one of the two displacement movements, the same operating performance of the crane for moving a load, that is to say to maintain fluid / dynamic control of the crane.

[0040] As previously indicated, the two movement movements that are grouped together are movement movements generally carried out successively. For example, lifting, orientation, and distribution movements are generally prohibited during a translation movement. Indeed, the control of a crane is most often done in two dimensions: vertically for lifting the load; and along the horizontal plane with the distribution and orientation of the boom to move the load in the working area of ​​the crane. This is why the translation movement can be grouped with each of these three movements. In other words, in different embodiments of the invention, one of the two shared actuators can correspond to a translation actuator, while the other shared actuator can correspond to a lifting actuator, or an orientation actuator, or a distribution actuator.

[0041] The distributing jib cranes integrate the four types of actuators mentioned. In two different embodiments, referred to above as the first configuration and the second configuration, it is possible for this type of crane to group the four displacement movements (and therefore the four actuators implementing them) into two groups, provided that two common variators are used for each of the two configurations.

[0042] The two configurations are established based on a compromise between objectives: - operational performance, for example in terms of speed or weight of loads that can be lifted and moved; and - safety, in particular for limiting the risk of overloading and controlling sway when moving the load. The actual performance of the control system can also be taken into consideration.

[0043] The first configuration is part of an application context of minimizing the risks of overloading and lack of control of the balance, even if it means not exploiting the functional performance of the crane to the maximum. For this configuration, the common variator is connected alternately to the orientation actuator and to the lifting actuator, while the other common variator is connected alternately to the distribution actuator and to the translation actuator. Thus, in the event of a momentary overload and / or swinging of the load during its movement, the crane operator retains control of the control of the distributing jib crane, being able to bring the distribution winch back towards the mast while vertically lowering the load, because he can act simultaneously on the distribution actuator and on the lifting actuator.

[0044] The second configuration prioritizes the operational performance of the crane, with a crane operator being able to control it until it reaches the operating limits authorized by the safety standards. In this second configuration, the common variator is connected alternately to the slewing actuator or to the translation actuator; and the other common variator is connected alternately to the distribution actuator or to the lifting actuator. Thus, the crane operator can move a load in the horizontal plane whose weight is equal to the limit imposed by the crane manufacturer and authorized by the torque / moment limiter, because he can act simultaneously on the slewing actuator and on the distribution actuator.

[0045] It should be noted that advantageously, the implementation of the two configurations requires the use of only two speed variators, instead of conventionally four.

[0046] According to a characteristic of the invention, the working actuators comprise a lifting actuator associated with a lifting movement, a slewing actuator associated with a slewing movement and a boom lifting actuator associated with a boom lifting movement for the crane which is of the luffing jib crane type, and the at least two shared actuators comprise the lifting actuator and the slewing actuator.

[0047] According to a characteristic of the invention, the boom lifting actuator is connected to another speed variator, among the speed variators, distinct from the common variator.

[0048] According to a characteristic of the invention, the other speed variator, called the other common variator, is connected to a translation actuator associated with a translation movement and to the boom lifting actuator via another distribution relay, said other distribution relay being controlled to alternately connect the other common variator with the translation actuator and the boom lifting actuator, so that the translation actuator and the boom lifting actuator operate alternately.

[0049] As is known, luffing jib cranes (with the jib being able to be articulated or not) are characterized by the fact that they do not have a distribution trolley. The lifting cable is always at the end of the jib, and the counter jib is shorter than that of a distributing jib crane; which allows this type of crane to be installed and assembled close to an obstacle.

[0050] Luffing jib cranes comprise at least one lifting actuator, one slewing actuator, one boom lifting actuator, and one translation actuator. The boom is raised (or lowered) to lift the load and move it closer (or further) to the mast. Crane operators must therefore, when operating this type of crane, compensate for the lifting or lowering of the load when tilting the boom to change the distribution radius.

[0051] For this type of crane, in one embodiment of the invention, the common variator is connected alternately to the slewing actuator or to the lifting actuator, and the other common variator is connected alternately to the lifting actuator or to the translation actuator.

[0052] This is the only possible configuration offering a good compromise in terms of operational performance and safety, because the crane operator is able to adjust the load by simultaneously performing a lifting movement and a raising movement. By acting simultaneously on the lifting actuator and on the boom raising actuator, the crane operator can therefore control in the horizontal plane by combining these two movements.

[0053] Again, the implementation of this configuration makes it possible to use two speed variators instead of four.

[0054] Optionally, in the case where the weight of the load is close to the load limit imposed by the crane manufacturer, and in order to secure the control of the latter, it is possible in an alternative embodiment of the invention to connect together to a common variator the lifting actuator and the raising actuator, or to group together the two most aggravating / risky movement movements.

[0055] The invention also relates to a crane comprising a control system as previously described.

[0056] The invention also relates to a control method for controlling a crane during operation, comprising at least: - a control step in which a crane operator controls the movement of a load by the crane on a control interface; - a step of receiving control signals from the control interface by a control-command system connected to the control interface; - a step of generation by the control-command system of pilot orders as a function of said pilot signals; - a step of transmitting control orders to speed variators which are connected to the control-command system and to work actuators ensuring the load displacement movements; - a control stage in which the speed variators transmit speed instructions to the working actuators according to the control orders; the control method being remarkable in that at least one of the speed variators, called common variator, is connected to at least two working actuators, called shared actuators, among the working actuators, via a distribution relay, and in that it comprises a switching step in which said distribution relay is controlled to alternately connect the common variator with each of the at least two shared actuators, so that the at least two shared actuators operate alternately. Brief description of the drawings

[0057] Other characteristics and advantages of the present invention will appear on reading the detailed description below, of a non-limiting example of implementation, made with reference to the appended figures in which:

[0058] [Fig-1] is a simplified schematic view of a distributing jib crane;

[0059] [Fig.2] is a simplified schematic view of a luffing jib crane;

[0060] [Fig.3] is a schematic view illustrating a first example of a control system for which the output of the control-command system is connected to a conventional speed variator controlling a working actuator, and to a common variator alternately controlling two working actuators via a distribution relay;

[0061] [Fig.4] is a schematic view illustrating a second example of a control system for which the output of the control-command system is connected to a common variator controlling two shared actuators via a distribution relay, and to another common variator also alternately controlling two shared actuators via another distribution relay;

[0062] [Fig.5] is a schematic view equivalent to [Fig.4] when the system of control is integrated into a distributing jib crane, and for which the shared actuators correspond to a translation actuator, an orientation actuator, a lifting actuator, and a distribution actuator, with the four shared actuators grouped in groups of two connected to a common variator such that the two groupings are part of a safety logic with in particular a minimization of the risks of overloading the distributing jib crane;

[0063] [Fig.6] is a schematic view equivalent to [Fig.4] and [Fig.5], for which the two groups of shared actuators are part of a logic of optimizing the performance of the distributing jib crane;

[0064] [Fig.7] is a schematic view equivalent to [Fig.4] when the control system is integrated into a luffing jib crane, and for which the shared actuators correspond to a translation actuator, a swing actuator, a lifting actuator, and a jib lifting actuator, with the four shared actuators grouped in groups of two connected to a common variator such that the two groupings are part of a logic of compromise between operational performance and safety.

[0065] [Detailed description of one or more embodiments of the invention]

[0066] The control system 1 proposed by the invention is conceivable for a crane with distributing boom 100 and also a luffing jib crane 200, simplified diagrams of which are respectively illustrated in [Fig.l] and [Fig.2].

[0067] Each of the two cranes 100, 200 comprises a mast 102, 202; and a rotating assembly rotated about an orientation axis, which is of vertical extension, by means of an orientation ring 108, 208 coupled to at least one orientation motor, causing the rotating assembly to sweep a circular area about the orientation axis.

[0068] The rotating assembly of a distributing jib crane 100 is formed by a jib 105 and a counter-jib 106 substantially aligned, and possibly a jib holder (or punch) with tie rods 107.

[0069] The rotating assembly of a luffing jib crane 200 is formed by a boom 205 which is lowered and raised angularly by means of at least one lifting cable 207, and by a base 206 on which the boom 205 is pivotally mounted. According to different designs of luffing jib crane 200, the boom 205 may or may not be composed of articulated boom elements.

[0070] For both types of crane 100, 200, a counterweight 109, 209 (or ballast block) is used to counterbalance the weight of a load lifted by the crane 100, 200 and to stabilize the latter during its slewing movements. In the distributing jib crane 100, the counterweight 109 is carried by the counter-jib 106, and in the luffing jib crane 200, the counterweight 209 is carried by the base 206.

[0071] The load is lifted by means of a hook 105, 205 located at the end of a block 104, 204 which is moved vertically by means of at least one lifting cable 111, 211.

[0072] In a distributing jib crane 100, the lifting cable 111 is suspended from a distributing trolley 103 movable in translation on a rolling path provided along the jib 105.

[0073] The luffing jib cranes 200 do not have a distribution trolley. The load is lifted depending on the inclination of the jib 205 and therefore on the winding or unwinding of the lifting cable 207.

[0074] As previously indicated, each of the load displacement movements achievable by a crane 100, 200 is implemented by a dedicated electric working actuator. The working actuators conventionally comprise: - a lifting winch coupled to the lifting cable and used to vertically raise and lower the load, i.e. a lifting actuator; - an orientation actuator coupled to the orientation ring 108, 208 and used to orient the rotating assembly around the orientation axis; - a translation actuator which is used to translate the crane 100, 200 on a rail in the case where the crane is intended to be mobile as a whole on the rail; - for cranes with distributing booms 100, a distribution winch coupled to a distribution cable fixed to the distribution trolley 103 and which serves to distribute the load along the boom 105 by means of the distribution trolley 103, i.e. a distribution actuator; - for luffing jib cranes 200, a jib lifting actuator coupled to the lifting cable 207 and which serves to angularly raise or lower the jib 205.

[0075] With reference to [Fig. 3] and [Fig. 4], each of the working actuators, which bear the references 6, 61, 62, 63 and 64 in these Figures, is connected to a speed variator 4, 41, 42 provided to regulate, as a function of speed setpoints S6, S61, S62, S63, S64, the speed of the electric motor of the working actuator 6, 61, 62, 63, 64 for the purposes of motion control, management of consumed energy, reduction of mechanical stress on motor control applications, etc.

[0076] With reference to [Fig.3] to [Fig.7], the control system 1 of the invention comprises several elements / components contributing to the implementation of a control method.

[0077] The control system 1 firstly comprises a control interface 2 to enable a crane operator during a control step to control movements of a load that can be carried out by the crane 100, 200. According to different design modes of the cranes 100, 200, the control interface 2 can be installed in a control cabin 110, 210 of the crane 100, 200 (in the form of a control console). control / dashboard with screens), or come in the form of a radio control or a remote control station. In all cases, it includes at least one control lever and buttons.

[0078] When the crane operator interacts with the control interface 2 to carry out a movement, the control interface 2 generates control signals DS which are received during a reception step by a control-command system 3 which is physically connected and / or which is in communication with the control interface 2.

[0079] From the control signals DS, the control-command system 3 generates during a generation step control orders D01, D02, D03 which it then transmits during a transmission step to speed variators 4, 41, 42 so that they control the working actuators 6, 61, 62, 63, 64 for the implementation of the movement(s) of movement of the load desired by the crane operator. Depending on the nature of the control signals DS representative of the movement(s) to be carried out, the speed variators 4, 41, 42 receive or not the control orders D01, D02, D03 emitted by the control-command system 3 depending on whether or not they control the working actuators 6, 61, 62, 63, 64 in charge of the movement.

[0080] With reference to [Fig.3] and 4, two general examples of application context are presented.

[0081] In the application context of [Fig.3], the control system 1 comprises: - three working actuators 6, 61, 62, namely a first working actuator 61, a second working actuator 62 and a third working actuator 6; - two speed variators 4, 41, namely a first speed variator 41 and a second speed variator 4.

[0082] The first speed variator 41 is connected to the first working actuator 61 and to the second working actuator 62 via a distribution relay 51; the first working actuator 61 and the second working actuator 62 thus constitute shared actuators, in the sense that they are connected to the same first speed variator 41, called the common variator. The second speed variator 4 is connected to the third actuator 6 alone.

[0083] Thus, the control-command system 3 is connected to these two speed variators 4, 41 respectively receiving control orders DO1, DO2 such that the second speed variator 4 is connected and controls the only third working actuator 6, and the first speed variator 41, or common variator, controls the two shared actuators 61, 62.

[0084] In the application context of [Fig.4], the control system 1 comprises: - four working actuators 61, 62, 63, 64, namely a first working actuator 61, a second working actuator 62, a third working actuator 63 and a fourth working actuator 64; - two speed variators 41, 42, namely a first speed variator 41 and a second speed variator 42.

[0085] The first speed variator 41 is connected to the first working actuator 61 and to the second working actuator 62 via a first distribution relay 51; the first working actuator 61 and the second working actuator 62 thus constitute shared actuators, in the sense that they are connected to the same first speed variator 41, called the common variator.

[0086] The second speed variator 42 is connected to the third working actuator 63 and to the fourth working actuator 64 via a second distribution relay 52, also called another distribution relay; the third working actuator 63 and the fourth working actuator 64 thus constitute other shared actuators, in the sense that they are connected to the same second speed variator 42, called another common variator.

[0087] Thus, the control-command system 3 is connected to these two speed variators 41, 42 respectively receiving control orders DO1, DO3 such that the first speed variator 41, or common variator, controls the two shared actuators 61, 62, and the second speed variator 42, called the other common variator, controls the other two shared actuators 63, 64.

[0088] Each of the speed variators 4, 41, 42 receives an electrical power E, El, E2 from an electrical supply network. Optionally, and as illustrated in [Fig.3] and [Fig.4], the speed variators 4, 41, 42 may be coupled to energy dissipation devices in order to prevent any overheating of the speed variators 4, 41, 42.

[0089] The two application contexts presented [Fig.3] and [Fig.4] are not exhaustive / limitative. The control system 1 may comprise, depending on the needs, that is to say the number of displacement movements to be executed, more working actuators 6; 61, 62; 63, 64 and speed variators 4; 41; 42 (whether these are speed variators 4 connected to a single working actuator 6 or common variators 41, 42 connected to two shared actuators 61, 62, 63, 64).

[0090] It is thus possible to equip a crane 100; 200 with several common variators 41; 42, as long as it is possible depending on the type of crane 100; 200 to group together two displacement movements to be carried out alternately (and therefore not simultaneously).

[0091] Conceptually, the two movements implemented by the two shared actuators 61, 62 connected to the common variator 41 cannot be carried out simultaneously but alternatively. This alternation is ensured in particular by means of a distribution relay 51. Consequently, the crane operator must complete one of two movements (for example that associated with the first working actuator 61) if it wishes to initiate the other of the two movements (for example that associated with the second working actuator 62). The same applies to the two movements implemented by the two other shared actuators 63, 64 connected to the other common variator 42; the alternation of which is ensured by means of the other distribution relay 52.

[0092] In the case where the crane operator attempts to implement the two displacement movements associated with the updated actuators 61, 62, 63, 64 of the same common variator 41, 42 simultaneously, the control interface 2 displays an error message sent by the control-command system 3 and the action of the crane operator is neutralized, that is to say that neither of the two movements is initiated during his attempt. Thus, a tapping by the crane operator, that is to say a control by pulse alternately on the controls controlling two displacement movements, is automatically detected then neutralized.

[0093] The distribution relays 51, 52 each have two switching configurations which are: - a first switching configuration in which the distribution relay 51, 52 connects the common variator 41, 42 to a first of the two shared actuators 61, 62, 63, 64 (for example the first working actuator 61 and the third working actuator 63) which it controls, and cuts the connection with a second of the two shared actuators 61, 62, 63, 64 (for example the second working actuator 62 and the fourth working actuator 64) which it therefore cannot control; and - a second switching configuration in which the distribution relay 51, 52 connects the common variator 41, 42 to the second of the two shared actuators 61, 62, 63, 64 (for example the second working actuator 62 and the fourth working actuator 64) which it controls, and cuts the connection with the first of the two shared actuators 61, 62, 63, 64 (for example the first working actuator 61 and the third working actuator 63) which it therefore cannot control.

[0094] With reference to Figures 4 and 5, when the speed variator 4 receives the control order DO2 associated with it, from the control-command system 3, the latter then transmits during a control step a speed instruction S6 to the working actuator 6 so that the movement that it implements is carried out at a certain speed.

[0095] Depending on the movement to be implemented by one of the two shared actuators 61, 62 (or 63, 64), the common variator 41 (or the other common variator 42) sends to the distribution relay 51 (or to the other distribution relay 52), during the control step, in addition to the speed setpoint S61, S62 (or S63, S64), a distribution setpoint DC1 (or DC2). According to this distribution setpoint DC1 (or DC2), the distribution relay 51 (or the other distribution relay 52) remains in its confi current tilting configuration or changes the tilting configuration, so that the speed setpoint S61 or S62 (or S63 or S64) is transmitted to the relevant shared actuator 61 or 62 (or 63 or 64) for the implementation of the desired movement.

[0096] In an embodiment of the invention where the crane operator wishes to perform a first movement associated with a first of the two shared actuators 61, 62, 63, 64, then a second movement associated with the second of the two shared actuators 61, 62, 63, 64, following the end of the first movement (which is estimated by the control-command system 3, and possibly confirmed by equipment of the crane 100; 200 such as sensors), the crane operator will have to wait a short predefined delay (of a few seconds for example) to initiate the second movement. In the case where the crane operator attempts to initiate the second movement during this delay, the control-command system 3 issues an error message. In order to warn the crane operator that the time limit has expired, it is possible for the control interface 2 to warn him by means of a text message or a visual indication displayed on a screen, and / or an audible signal.

[0097] In a second embodiment of the invention, the distribution relay 51 and the other distribution relay 52 are controlled by the control-command system 3. Depending on the control signal DS received by the control-command system 3, and which is representative of one of the two displacement movements that the crane operator wishes to perform, the distribution relay 51 and the other distribution relay 52 connect the output of the common variator 41 and of the other common variator 42 to the input of the shared actuator 61, 62; 63, 64 in charge of said displacement movement; so that the common variator 41 and the other common variator 42 to the shared actuator 61, 62; 63, 64 to which they are each connected the power necessary for carrying out the displacement movement at the desired speed.

[0098] In a third embodiment of the invention, in the context of an application context where the speeds of the displacement movements must be rigorously precise, servo feedback 7 can be implemented for example with speed measuring devices present on the crane 100; 200, such as sensors, which are shaped to measure said speeds (for example the speeds of the movements and / or the speeds of the working actuators) during the performance of the displacement movements, then to transmit the measured speeds to the speed variators 4; 41; 42.

[0099] The speed variators 4; 41; 42 then compare the measured speed values ​​with the speed setpoints S6; S61, S62; S63, S64 contained in the control order; providing, depending on whether the measured speeds are lower (respectively higher) than the speed setpoints S6; S61, S62; S63, S64, more (respectively less) power to the working actuators 6; 61, 62; 63, 64. In an alternative embodiment of the invention, the speed variators 4; 41; 42, once the speed measurements have been received, transmit them to the control-command system 3 which will compare them with the control signals DS sent by the control interface 2. Depending on the comparison results, the control-command system 3 adapts or not the control order DO1; DO2; DO3 transmitted to the speed variators 4; 41; 42 for controlling the working actuators 6; 61, 62; 63, 64. In another alternative embodiment of the invention, it is conceivable that the speeds measured by the sensors are transmitted directly to the control-command system 3.

[0100] In a fourth embodiment of the invention, in order to regulate the speed of the displacement movements, it is conceivable that at least one of the working actuators 6; 61, 62; 63, 64 of the crane 100; 200 is coupled with a brake 8 (which is the case for example of the orientation actuator), which brake is controlled in two variant embodiments of the invention: - either by the speed variator 4; 41; 42, which sends a braking order BD to the brake 8, - either by the control-command system 3 itself.

[0101] In the examples presented [Fig.3] and [Fig.4], a brake 8 is coupled with the first working actuator 61 connected to the common variator 41. In order to regulate the speed of a displacement movement, it is also conceivable that the brake 8 communicates its state 81 (open brake or closed brake) to the common variator 41 connected to the first working actuator 61 to which it is coupled, or else to the control system 3.

[0102] As previously indicated, the working actuators 6; 61, 62; 63, 64 may in particular comprise: a lifting actuator associated with a lifting movement ML; an orientation actuator associated with an orientation movement MO; a translation actuator associated with a translation movement MT; a distribution actuator associated with a distribution movement MD if the crane is a crane with a distributing jib 100; or even a jib lifting actuator associated with a jib lifting movement MR if the crane is a crane with a luffing jib 200.

[0103] As explained so far, a common variator 41 (or 42) alternately controls two shared actuators 61, 62 (or 63, 64) each implementing a displacement movement.

[0104] With reference to [Fig.4] to 7, in the case where the control system 1 comprises several common variators 41, 42, the displacement movements (and therefore the shared actuators 61, 62, 63, 64 implementing them) attached to the latter are ergonomically chosen to retain, or at least approach, the same operating performance of the crane for moving a load, i.e. to maintain smooth / dynamic control of the crane.

[0105] In other words, the shared actuators 61, 62 (or 63, 64) are associated with two movements which are generally never carried out simultaneously, but successively.

[0106] The proposed control system 1 advantageously makes it possible to associate two distinct displacement movements that a crane 100; 200 can carry out when it is working, and therefore to associate the two working actuators 61, 62 (or 63, 64) each responsible for one of the two movements, with a single shared speed variator 41 (or 42).

[0107] For example, lifting, orientation, and distribution movements are generally prohibited during a translation movement. Indeed, the control of a crane 100; 200 is most often done in two dimensions: vertically for lifting the load; and along a horizontal plane for the distribution and orientation of the boom 105; 205 to move the load in the working position of the crane 100; 200. This is why the translation movement can be grouped with each of these three movements. In other words, in different embodiments of the invention, one of the two shared actuators 61, 62; 63, 64 can correspond to a translation actuator associated with a translation movement MT, while the other shared actuator 61, 62; 63, 64 can for example correspond to a lifting actuator, or an orientation actuator.

[0108] The distributing jib cranes 100 integrate at least these three types of actuators as well as a distribution actuator associated with a distribution movement MD. In two different embodiments, hereinafter referred to respectively as the first and second configurations, it is possible for this type of crane to group the four displacement movements (and therefore the four actuators implementing them) into two groups by means of the common variator 41 and the other common variator 42.

[0109] The two configurations are established based on a compromise between objectives: - operational performance, for example in terms of speed or weight of loads that can be lifted and moved; and - safety, in particular for limiting the risk of overloading and controlling the swing of the distributing jib crane 100 when moving the load. The actual performance of the control-command system 3 can also be taken into consideration.

[0110] The first configuration, illustrated [Fig.5], is part of an application context of minimizing the risks of overload and lack of balance control, even if it means not not exploit the functional performance of the 100 distributing jib crane to the maximum, and in which: - the first speed variator 41, or common variator, is connected to the first working actuator 61 and to the second working actuator 62 via the first distribution relay 51, where the first working actuator 61 is the lifting actuator and the second working actuator 62 is the orientation actuator; and - the second speed variator 42, or other common variator, is connected to the third working actuator 63 and to the fourth working actuator 64 via the second distribution relay 52, where the third working actuator 63 is the translation actuator and the fourth working actuator 64 is the distribution actuator.

[0111] Thus, in this first configuration, in the event of a momentary overload and / or swinging of the load during its movement, the crane operator retains control of the piloting of the distributing jib crane 100, being able to bring the distributing winch back towards the mast 102 while vertically lowering the load, because he can act simultaneously on the distributing actuator (here fourth working actuator 64) and on the lifting actuator (here first working actuator 61).

[0112] The second configuration, illustrated [Fig.6], is part of a context where the operational performance of the distributing jib crane 100 is prioritized, with a crane operator able to pilot it until it reaches the operating limits authorized by the safety standards, and in which: - the first speed variator 41, or common variator, is connected to the first working actuator 61 and to the second working actuator 62 via the first distribution relay 51, where the first working actuator 61 is the lifting actuator and the second working actuator 62 is the distribution actuator; and - the second speed variator 42, or other common variator, is connected to the third working actuator 63 and to the fourth working actuator 64 via the second distribution relay 52, where the third working actuator 63 is the translation actuator and the fourth working actuator 64 is the orientation actuator.

[0113] Thus, in this second configuration, the crane operator can move a load in the horizontal plane whose weight is equal to the limit imposed by the crane manufacturer and authorized by the torque / moment limiter, because he can act simultaneously on the orientation actuator (here fourth working actuator 64) and on the distribution actuator (here second working actuator 62).

[0114] It should be noted that in the examples of Figures 5 and 6, the translation actuator may be absent, and in this case the distribution actuator is the only one connected to the second speed variator 42 without the second distribution relay 52 (case of [Fig.5]), or the orientation actuator is alone connected to the second speed variator 42 without the second distribution relay 52 (case of [Fig.6]).

[0115] With reference to [Fig.7], the luffing jib crane 200 incorporates a translation actuator (optional), a lifting actuator, a swing actuator, and also as previously specified a boom lifting actuator. By means of this boom lifting actuator, the boom 205 can be raised (respectively lowered) to lift the load (respectively lower the load) and move it closer (respectively further) to the mast 202. Consequently, when operating a luffing jib crane 200, the crane operator must compensate for the lifting or lowering of the load, by means of the lifting actuator, when tilting the boom 205 to change the distribution radius.

[0116] The translation, lifting, orientation and raising movements can be grouped into two groups of displacement movements such that, on the one hand, the lifting actuator and the orientation actuator are shared and, on the other hand, the boom lifting actuator and the translation actuator are shared; in other words: - the first speed variator 41, or common variator, is connected to the first working actuator 61 and to the second working actuator 62 via the first distribution relay 51, where the first working actuator 61 is the lifting actuator and the second working actuator 62 is the orientation actuator; and - the second speed variator 42, or other common variator, is connected to the third working actuator 63 and to the fourth working actuator 64 via the second distribution relay 52, where the third working actuator 63 is the translation actuator and the fourth working actuator 64 is the boom lifting actuator.

[0117] In this illustrated configuration [Fig.7], a good compromise is thus proposed in terms of operational performance and safety, because the crane operator is able to adjust the load by simultaneously performing a lifting movement ML and a raising movement MR, because he can act simultaneously on the lifting actuator (here first working actuator 61) and on the boom raising actuator (here fourth working actuator 64), and therefore the crane operator can control in the horizontal plane by combining these two movements MR, ML.

[0118] Optionally, in the case where the weight of the load is close to the load limit imposed by the manufacturer of the luffing jib crane 200, and in order to secure the control of the latter, it is possible in an alternative embodiment of the invention to connect together to a common variator 41 the lifting actuator and the jib lifting actuator, and therefore to group the two together most aggravating / risky MR, ML movements.

[0119] It should be noted that in the example of [Fig.7], the translation actuator may be absent, and in this case the boom lifting actuator is alone connected to the second speed variator 42 without the second distribution relay 52.

Claims

Claims

1. Control system (1) for working control of a crane (100; 200), comprising at least: - a control interface (2) to allow a crane operator to control movements of movement of a load by the crane (100; 200); - a control-command system (3) connected to the control interface (2) to receive control signals (DS) from the control interface (2) and generated control orders (DO1; DO2; DO3) as a function of said control signals (DS); - working actuators (6; 61, 62; 63, 64) ensuring the movements of movement of the load; - speed variators (4; 41; 42) which are connected to the control-command system (3) and to the working actuators (6; 61, 62; 63, 64) to receive the control commands (DO1; DO2; DO3) from the control-command system (3) and transmit to the working actuators (6; 61, 62; 63, 64) speed setpoints (S6; S61, S62;S63, S64) depending on the pilot orders (DO1; DO2; DO3); the control system (1) being characterized in that at least one of the speed variators (4; 41; 42), called the common variator (41; 42), is connected to at least two working actuators, called shared actuators (61, 62; 63, 64), among the working actuators (6; 61, 62; 63, 64), via a distribution relay (51; 52), said distribution relay (51; 52) being controlled to alternately connect the common variator (41; 42) with each of the at least two shared actuators (61, 62; 63, 64), so that the at least two shared actuators (61, 62; 63, 64) operate alternately.;

2. Control system (1) according to claim 1, in which the distribution relay (51; 52) is controlled by the common variator (41; 42) which is configured to send to said distribution relay (51; 52) distribution instructions (DC1; DC2) as a function of the control orders (DO2; DO3) coming from the control-command system (3).

3. Control system (1) according to claim 1 or 2, in which the control-command system (3) is configured to transmit to the control interface (2) an alert message intended for the crane operator when said crane operator acts on the control interface (2) in order to simultaneously control two movements associated with shared actuators (61, 62; 63, 64) which can only operate alternately.

4. A control system (1) according to any one of claims 1 to 3, wherein the working actuators (61, 62; 63, 64) comprise a lifting actuator associated with a lifting movement (ML), a slewing actuator associated with a slewing movement (MO) and a distribution actuator associated with a distribution movement (MD) for the crane which is of the distributing jib crane type (100), and the at least two shared actuators (61, 62; 63, 64) comprise the lifting actuator and the slewing actuator in a first configuration, or the at least two shared actuators (61, 62; 63, 64) comprise the lifting actuator and the distribution actuator in a second configuration.

5. Control system (1) according to claim 4, in which the distribution actuator is connected to another speed variator (42), among the speed variators (41; 42), distinct from the common variator (41) in the first configuration, or the orientation actuator is connected to another speed variator (42), among the speed variators (41; 42), distinct from the common variator (41) in the second configuration.

6. Control system according to claim 5, in which: - in the first configuration: the other speed variator (42), called other common variator, is connected to a translation actuator associated with a translation movement (MT) and to the distribution actuator via another distribution relay (52), said other distribution relay (52) being controlled to alternately connect the other common variator (42) with the translation actuator and the distribution actuator, so that the translation actuator and the distribution actuator operate alternately;or - in the second configuration: the other speed variator (42), called the other common variator, is connected to a translation actuator associated with a translation movement (MT) and to the orientation actuator via another distribution relay (52), said other distribution relay (52) being controlled to alternately connect the other common variator (42) with the translation actuator and the orientation actuator, so that the translation actuator and the orientation actuator operate alternately.;

7. A control system (1) according to any one of claims 1 to 3, wherein the working actuators (61, 62; 63, 64) comprise a lifting actuator associated with a lifting movement (ML), an ac- orientation donor associated with an orientation movement (MO) and a boom lifting actuator associated with a boom lifting movement (MR) for the crane which is of the luffing jib crane type (200), and the at least two shared actuators (61, 62; 63, 64) comprise the lifting actuator and the orientation actuator.

8. Control system (1) according to claim 7, in which the boom lifting actuator is connected to another speed variator (42), among the speed variators (41; 42), distinct from the common variator (41).

9. Control system (1) according to claim 8, in which the other speed variator (42), called other common variator (42), is connected to a translation actuator associated with a translation movement (MT) and to the boom lifting actuator via another distribution relay (52), said other distribution relay (52) being controlled to alternately connect the other common variator (42) with the translation actuator and the boom lifting actuator, so that the translation actuator and the boom lifting actuator operate alternately.

10. Crane (100; 200) comprising a control system (1) according to any one of the preceding claims.

11. A method of controlling a crane (100; 200) during operation, comprising at least: - a controlling step in which a crane operator controls movements of movement of a load by the crane (100; 200) on a controlling interface (2); - a step of receiving control signals (DS) from the controlling interface (2) by a control-command system (3) connected to the controlling interface (2); - a step of generating by the control-command system (3) control orders (DO1; DO2; DO3) as a function of said control signals (DS); - a step of transmitting the control commands (DO1; DO2; DO3) to speed variators (4; 41; 42) which are connected to the control-command system (3) and to working actuators (6; 61, 62; 63, 64) ensuring the movements of displacement of the load; - a control step in which the speed variators (4; 41; 42) transmit to the working actuators (6;61, 62; 63, 64) speed instructions (S6; S61, S62; S63, S64) according to the orders; piloting (DO1; DO2; DO3); the control method being characterized in that at least one of the speed variators (4; 41; 42), called common variator (41; 42), is connected to at least two working actuators, called shared actuators (61, 62; 63, 64), among the working actuators (6; 61, 62; 63, 64), via a distribution relay (51; 52), and in that it comprises a switching step in which said distribution relay (51; 52) is controlled to alternately connect the common variator (41; 42) with each of the at least two shared actuators (61, 62; 63, 64), so that the at least two shared actuators (61, 62; 63, 64) operate alternately.

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