EP1829812B1 - Control device, in particular for a handling machine - Google Patents

Description

The invention relates to a control device for a handling machine, particularly for the handling of people.

A state of the art closest is described in the document DE-A-19612 423 .

The invention also relates to a personal handling machine equipped with a device according to the invention.

The invention is particularly useful in its application to the control of telescopic boom lifts carrying a basket or a load support tray.

The handling of persons must comply with strict safety rules to avoid any risk of overload or instability of the handling machine.

Self-propelled lifting machines must have a control system for processing movement authorizations based on the load in the basket, in accordance with EN 280, which defines the general rules for personal handling design.

In the case of elevating machines comprising hydraulic actuators such as cylinders, it is known to detect the hydraulic pressures of the cylinders carrying the load and to memorize a large number of pressure values or forces obtained by measurements in various configurations of the machine. vacuum lift: static, uphill movement, downhill movement.

Thus, with regard to certain load-handling equipment and / or persons having several cylinders, for a static configuration of the machine, it is necessary to record numerous pressure or force values corresponding to the lifting angles and the values of the machine. Telescoping necessary to explore all the positions that can be achieved with the machine. The same is true of rising and falling configurations, which leads to several hundreds of pressures or forces to be memorized.

From the stored values, linear interpolations can then be performed to compare the calculated load with the allowed load in the corresponding configuration.

A first object of the invention is to improve and simplify the method for calculating the on-board load by reducing the number of pressures to be memorized in order to calculate the load on board and to control the movements of the machine, and by processing the authorizations of Reliable movement, simple and fast.

A second object of the invention is to provide a new control device more reliable and faster than the control systems of the prior art.

Safety systems are known for handling machines with telescopic arms to prevent the tilting of the machine. These safety systems use at least one sensor generally attached to the rear axle to detect its support on the ground and to provide a signal to a comparator for providing input to a control means of a proportional hydraulic valve, so as to to reduce the feed rate of a hydraulic actuator, so that the speed of movement of the load is progressively reduced when lowering the telescopic arm

These safety systems are generally satisfactory but have the disadvantage of having a reduced reliability, to impose the fact that the rear axle is oscillating and to limit the space of movement of the telescopic arm in a given machine configuration.

A third object of the invention is to use the calculated load of the machine to determine, in the corresponding machine configuration, the load displacement chart by acting on the load displacement speeds.

The subject of the invention is a control device, in particular for a person handling machine, comprising means for calculating the on-board load and for defining the operating charts from said calculated onboard load.

• lesdits moyens pour calculer la charge embarquée et pour définir des abaques de fonctionnement à partir de ladite charge embarquée calculée comportent un calculateur de gestion et un calculateur de sécurité.
• le calculateur de gestion utilise un nombre réduit de paramètres d'étalonnage obtenus en maintenant la longueur d'un bras de manutention constante.
• les calculateurs de gestion et de sécurité sont reliés par un bus de communication.
• les calculateurs de gestion et de sécurité reçoivent de manière indépendante des signaux en provenance de capteurs de mesure redondants et indépendants.
• le calculateur de sécurité vérifie la cohérence des mesures indépendantes effectuées pour les capteurs indépendants.
• le dispositif comporte des moyens pour déterminer la configuration d'une machine de manutention.
• la configuration de la machine de manutention est déterminée dans le groupe comprenant : une configuration statique, une configuration en mouvement de montée, une configuration en mouvement de descente.
• le dispositif gère les autorisations de mouvement en fonction de la configuration de la machine de manutention.

According to other alternative features of the invention:

• said means for calculating the on-board load and for defining operating charts from said calculated onboard load comprise a management computer and a security calculator.
• the management computer uses a reduced number of calibration parameters obtained by maintaining the length of a constant handling arm.
• the management and security computers are connected by a communication bus.
• the management and safety computers independently receive signals from redundant and independent measuring sensors.
• the safety calculator checks the consistency of the independent measurements made for the independent sensors.
• the device comprises means for determining the configuration of a handling machine.
• the configuration of the handling machine is determined in the group comprising: a static configuration, a climbing movement configuration, a downhill motion configuration.
• the device manages the movement authorizations according to the configuration of the handling machine.

The invention also relates to a handling machine, including persons, comprising a device according to the invention.

• La figure 1 représente schématiquement un ordinogramme de fonctionnement d'un dispositif selon l'invention.
• La figure 2 représente schématiquement un diagramme matériel d'un dispositif selon l'invention.
• La figure 3 représente schématiquement une machine de manutention selon l'invention.

The invention will be better understood from the following description given by way of nonlimiting example with reference to the accompanying drawings in which:

• The figure 1 schematically represents a flow chart of operation of a device according to the invention.
• The figure 2 schematically represents a hardware diagram of a device according to the invention.
• The figure 3 schematically represents a handling machine according to the invention.

With reference to the figure 1 , a flowchart of operation of a device according to the invention comprises the steps of the calculation means of a control device according to the invention.

The flowchart comprises a first part intended to evaluate the load embedded in a basket or a handling machine tray, and a second part intended to define the operating charts of the handling machine according to the configuration of the machine of the machine. handling and the embedded load calculated in the first part.

The first part begins with a step 100 of calibration of a handling machine maintaining the length of the telescopic arm constant.

This calibration step 100 is performed by varying only the angle of the lifting arm of the machine corresponding to the angle of inclination of the basket or tray relative to the lifting arm: indeed, to maintain, in this calibration step 100, the basket or tray parallel to the frame, these two angles must remain equal.

Calibrating the constant arm length handling machine makes it possible to memorize a small number of pressure or effort values. Thus, it is possible to memorize only ten values of force or pressure of the lifting cylinder corresponding to ten lifting angles for a static configuration of the machine.

It is the same with respect to the upward movement configuration and the downhill movement configuration, which leads to a total of thirty pressures to be memorized for the lifting cylinder of the handling machine described with reference to the figure 3 .

The same operations are performed, in this calibration step 100, for the tilt cylinders, which leads to a total of thirty pressures to be memorized by tilt cylinder of the handling machine described with reference to FIG. figure 3 .

The values of forces or pressures thus measured are compared, at a step 101, with values of theoretical forces or pressures obtained by calculation at a step 102, and their differences are memorized at a step 103 in the form of force corrections. or pressure corrections.

From the values of the corrections stored in step 103, at a maximum hydraulic flow rate, corrections corresponding to each configuration of the handling machine according to the invention can be determined.

In step 104, the lever arms of the hydraulic actuators of the machine and the geometric characteristics of the machine are determined by acquisition of measurements from corresponding sensors and processing of the signal received from these sensors.

In step 105, the forces or other quantities related to the theoretical idle forces provided by the tilt cylinders are calculated as a function of the geometric characteristics determined in step 104 and the configuration of the handling machine.

In step 106, the forces or other quantities related to the theoretical idle forces of the lifting actuators are calculated as a function of the geometric characteristics determined in step 104 and of the configuration of the handling machine.

In step 107, the quantities relating to the previously calculated idle forces of the inclination and lifting jacks are corrected by correcting them by the corrections of forces or pressures corresponding to the configuration of the machine, taking account of the flow rates. hydraulic actuators in the corresponding hydraulic actuators.

Thus, the corrections of the correction values as a function of the flow rate are done by extrapolation between the stored corrections with maximum hydraulic flow rate and at a zero flow rate.

In step 108, the load of the handling machine is calculated by solving the lever arm equations taking into account the corrected hydraulic forces determined in the previous steps.

This gives a calculated load whose value corresponds to the forces or other quantities directly translating these forces measured by the sensors equipping the hydraulic actuators of the handling machine according to the invention.

In step 200, the calculated load determined in step 108 of the first part is used to establish a tilt equilibrium equation of the handling machine according to the invention.

A handling machine according to the invention comprises a frame whose tendency to tilt depends on its weight, the weight of the telescopic arm, the weight of the basket or any other load handling device and the calculated weight of the load, as well as to any aggravating efforts due for example to a manual action or action of the wind likely to overturn the handling machine according to the invention.

The handling machine according to the invention thus comprises a center of gravity linked to the chassis and depending on the ground position of the chassis and of these ground support points, and a second center of gravity corresponding to the displaceable assembly comprising the telescopic arm, the basket or other load-holding device and the load located inside or on said device.

In the case where the handling machine rests on its wheels, step 201 calculates the tilting moment with respect to the ground contact line of the front wheels of the handling machine according to the invention.

In the case where the handling machine according to the invention comprises outriggers deployed and resting on the ground, step 202 calculates the moment of tilting with respect to the line defined by the stabilizers of the handling machine according to the invention. 'invention.

In step 203, the equilibrium general equation of the machine is expressed around its overturning point, corresponding to a minimum limit load on the rear axle, taking into account possible manual forces and the reversal moment likely to occur. to be in the wind.

In step 204, the quantities representing the forces (forces or pressures) of the corresponding lifting actuators as a function of the load on the rear axle are expressed in order to establish the setpoint laws of the actuators as a function of the maximum authorized speeds and the nature movements: aggravating or degrading for the stability of the handling machine according to the invention.

With reference to the figure 2 a hardware diagram of a control device according to the invention comprises a management computer 1 and a security computer 2 communicating with each other via a link bus, for example a CAN bus. The computers 1 and 2 receive in parallel independent signals in from redundant sensors equipping a handling machine according to the invention.

This personal handling machine according to the invention comprises one or a pair of jacks 10a, 10b of inclination, a lifting cylinder 11, at least one telescoping jack 12, possibly a pair of jacks 13a, 13b of stabilizers and measuring sensors fixed on the machine according to the invention.

The tilt cylinders 10a, 10b are equipped with sensors making it possible to define the forces they exert, as well as the lifting cylinder 11, or the telescoping cylinder (s) 12.

Any stabilizer cylinders 13a, 13b are equipped with sensors to know their states: retracted or supported on the ground.

The chassis C of the machine according to the invention also carries two inclination sensors. The beam 14 telescopic arm also carries two redundant tilt sensors relative to the horizontal.

The signals transmitted by the aforementioned redundant sensors are transmitted independently and distributed between the management computer 1 and the security computer 2.

The computers 1 and 2 cooperate with one another to ensure a secure and controlled operation of the device according to the invention, after storage of the parameters obtained by calibration and geometric constants of the machine according to the invention.

The signals coming from the sensors make it possible to determine the configuration as well as the geometry of the machine and to select the parameters corresponding to the determined configuration.

Each computer 1 or 2 constantly checks the operation of the measurement sensors, the coherence of the measurements between redundant or duplicated sensors, the operation of the communication bus 3 and automatically cuts off the motor M of the machine according to the invention in the event of a fault.

The management computer 1 performs the calculations of the operating flowchart described with reference to the figure 1 and manages the authorizations of movements of the tilt, lift and telescoping actuators of the machine according to the invention.

The security calculator 2 performs certain security calculations such as the calculation of the height of the tray or basket, the calculation of the stability and loading limits and checks the consistency of the results with the calculations made by the management computer 1.

Thresholds of coherence between controlled functions make it possible to decide on the relevance of the measurements and calculations carried out.

In case of recognized consistency of the results, the operation of the machine is normally possible.

In the case where the compared elements differ beyond the defined thresholds the machine according to the invention becomes secure by prohibiting all or part of its movements.

A safety member 15 is also activated when a push button 16 of the "dead man" type in the vicinity of the frame or a push button 17 of the "dead man" type located in the tray or basket is not maintained for a predetermined duration less than ten seconds, which allows, when possible stabilizers are not in place, to limit by default the progress of the machine at slow speeds.

With reference to the figure 3 , a handling machine according to the invention comprises, in a known manner, a chassis C equipped with wheels and any stabilizers 13, in known manner carrying a telescopic arm 14 pivoting about a horizontal axis under the action of a jack 11 lifting.

The telescopic arm 14 contains at least one telescoping cylinder and carries at its end remote from the chassis C a tray or basket P or any other device intended to carry a load, subjected to the action of tilt cylinders 10 able to maintain said substantially horizontal device.

The self-propelled chassis C supports a motor and a control cabinet containing the computers 1 and 2 of the control device according to the invention.

The management computer 1 defines the calculation according to the flowchart described with reference to the figure 1 an abacus 20 surrounding a stability area allowing movements at maximum rates, and an abacus 21 defining with the abacus 20 a Intermediate zone in which outgoing or aggravating movements are allowed at reduced flows, and re-entrant or degrading movements are allowed at maximum or intermediate rates.

The security calculator 2 defines by calculation an abacus 22 corresponding to a security value for the stability of the machine according to the invention. As soon as the safety chart 22 is reached, the safety computer 2 cuts all the energies of the machine according to the invention by shutting down the heat engine and deactivating the safety member 15.

Charts 20, 21 and 22 of the figure 3 are established for deployed outriggers 13 defining a pivot line in front of the front wheels: of course, the computers 1 and 2 similarly define similar charts when the stabilizers 13 are retracted and define a pivot line on the front wheels.

The invention described with reference to a particular embodiment is not limited thereto, but on the contrary covers any modification of form and any variant embodiment within the scope of the appended claims.

In particular, the invention is also applicable to the control of load handling machines, such as variable reach trolleys, forklifts, loaders, public works equipment and the like.

Claims (9)

1. A control device for a handling machine making it possible to handle people, including means (1, 2) for calculating the onboard load and defining the operating charts (20, 21, 22) from said calculated onboard load, the means (1, 2) including a management computer (1), characterized in that the management computer (1) uses a reduced number of obtained calibration parameters (100) while keeping the length of a handling arm (14) constant.
2. The device according to claim 1, characterized in that said means (1, 2) for calculating the onboard load and defining the operating charts (20, 21, 22) from said calculated onboard load include a management computer (1) and a security computer (2).
3. The device according to claim 2, characterized in that the management and security computers (1, 2) are connected by a communication bus (3).
4. The device according to claim 2, characterized in that the management and security computers (1, 2) independently receive signals from redundant and independent measuring sensors.
5. The device according to claim 4, characterized in that the security computer (2) verifies the coherence of the independent measurements done for the independent sensors.
6. The device according to any one of the preceding claims, characterized in that the device includes means (1, 2) for determining the configuration of a handling machine.
7. The device according to claim 6, characterized in that the configuration of the handling machine is determined in a group comprising: a static configuration, an upward movement configuration, a downward movement configuration.
8. The device according to claim 6 or claim 7, characterized in that the device manages the movement authorizations based on the configuration of the handling machine.
9. A handling machine including a device according to any one of claims 1 to 8.

Images