FR2980184A1 - Method for managing displacement of boom lift of personnel, involves controlling and adjusting hydraulic flow of actuators producing movements of boom lift in continuous manner to impose linear velocity of constant evolution of basket - Google Patents

Abstract

The method involves measuring displacement of a telescopic arm by a sensor (13) and angle of elevation of the telescopic arm by the sensor. Position of a personnel receiving basket is calculated in rectangular coordinates by a calculator (10). Hydraulic flows of the actuators producing the movements of boom lift are controlled and adjusted continuously by a control system (17) to impose linear velocity of constant evolution of the basket. The telescopic arm is rotated with respect to a frame of boom lift by a turret of the boom lift. An independent claim is also included for a device for managing displacement of a boom lift of personnel.

Description

The invention relates to a displacement management method, in particular for personnel lifting platform. The invention also relates to a displacement management device, in particular for personnel lifting platform.

Personnel lifting platforms of known type are self-propelled personnel lifting vehicles of the type comprising a wheeled chassis supporting a telescopic arm articulated at the rear of the chassis about a substantially horizontal axis and comprising a personnel receiving basket. mounted on this telescopic arm. These known type of lifting lifts allow the elevation of 10 personnel using a large staff receiving basket may contain loads of heavy equipment or tools. These nacelles of personnel of known type have a high lifting capacity and a robust structure, both for the self-propelled chassis and the telescopic lifting arm. Some particular lifting aerial work platforms may have a turret allowing the telescopic arm to rotate relative to the chassis, to allow access to different locations without requiring the wheel chassis to be moved. In order to guarantee the safety of the personnel, it is necessary to limit the linear speed of the movements of the personnel receiving basket, thereby avoiding imbalances which may lead to personnel accidents and shocks likely to cause material damage. This linear speed of the personnel receiving basket is all the higher as the personnel receiving basket is further away from the wheeled chassis, for the same angular displacement speed of the articulated arm. For personnel lifting platforms with a turret, the linear speed of the personnel receiving basket increases as the personnel receiving basket is further away from the wheeled chassis, for the same angular speed of rotation of the machine. turret.

In known type of personnel lifts, in order to maintain the linear speed of the personnel receiving basket below a predetermined threshold in all the positions of the basket, the angular velocities of the movements are determined for a maximum distance between the basket and wheel chassis, which leads to unnecessarily low linear speeds when the basket is closer to the chassis. An object of the invention is to improve the known state of the art, by proposing a new method of management of displacement for personnel lifting platform. Another object of the invention is to improve the known state of the art by proposing a new displacement management device for personnel lifting platform. The invention relates to a displacement management method, in particular for personnel lifting platform, comprising the following steps: a) measuring the displacement of a telescopic arm; B) measuring the elevation angle of the telescopic arm; c) calculate the position in rectangular coordinates of the staff receiving basket; d) continuously control and adjust the hydraulic flows of the actuators producing the movements of the aerial platform to impose a linear speed of constant basket evolution. According to other alternative features of the invention: the invention also applies to the case of a personnel lifting platform with a turret allowing the telescopic arm to rotate relative to the frame. the horizontal component of the movement speed of the basket is kept below a predetermined threshold. the vertical component of the movement speed of the basket is kept below a predetermined threshold.

The invention also relates to a displacement management device, in particular for personnel lifting platform, comprising means for measuring the displacement of the telescopic arm, means for measuring the elevation angle of the telescopic arm, means for calculating the position in rectangular coordinates of the personnel receiving basket, means for continuously controlling and adjusting the hydraulic flows of the actuators producing the movements of the aerial platform to impose a linear speed of constant basket evolution.

According to other alternative features of the invention: the means for calculating the position in rectangular coordinates of the personnel receiving basket combine an angle sensor of the articulated arm (for example a rotary potentiometer), an extension sensor of the telescopic arm (for example a cable potentiometer), and a computer - the means for controlling and continuously adjusting the hydraulic flows of the actuators producing the movements of the aerial platform combine a computer knowing the position of the staff reception basket in coordinates Rectangular and controlling the engine speed driving the pump and / or proportional hydraulic valves sending the correct flow to the hydraulic actuators, so as to obtain a linear speed of the basket below a predetermined limit. The invention will be better understood from the description which follows, given by way of non-limiting example with reference to the accompanying drawings in which: Figure 1 shows schematically a lifting platform of personnel for the implementation of the invention. FIG. 2 diagrammatically represents a functional diagram for the implementation of the invention. FIG. 3 diagrammatically represents a set of tables for the implementation of the invention. Referring to FIG. 1, a personnel lifting platform comprises a chassis (1) mounted on four wheels (2). The frame (1) carries an orientation ring (3, 4) supporting a turret (5) rotatable about a vertical axis (A).

The turret (5) carries a telescopic arm (6) hinged about a substantially horizontal axis (6a). The telescopic arm (6) carries at its distal end a basket (7) for receiving personnel. The telescopic arm (6) is raised or lowered in the direction of the arrow B by the action of a lifting cylinder (8). The telescopic arm (6) extends or retracts in the direction of the arrow C to reach a desired location by an operator located in the basket (7) for receiving personnel. Motion sensors are provided for measuring the raising or lowering of the telescopic arm (6) in the direction of the arrow B and telescoping or retracting of the telescopic arm in the direction of the arrow C. An on-board computer on the aerial work platform deduces measurements made continuously the position of the basket in the work area. The onboard computer on the aerial platform processes the continuous measurements of the movements according to the arrows B and C to derive the speed of movement of the basket, and in particular the linear velocity and their components in trirectangular coordinates to increase the safety of the user. For this purpose, the computer comprises a program containing a control loop for imposing on the basket (7) staff receiving a movement at constant linear speed. This constant speed of evolution of the reception basket in the space obtained thanks to the invention thus makes it possible to avoid shocks or clashes due to the displacement, while increasing the stability of the personnel on board the reception basket. In FIG. 2, a computer (10) embarked on the aerial platform is connected to a memory (11) containing several tables of coefficients established according to the position in rectangular coordinates of the personnel reception basket: a first table of coefficients of Hydraulic fluid flow correction imposing the maintenance of a constant speed of the "turret rotation" function, a second table of hydraulic fluid flow correction coefficients imposing to maintain a constant speed, on the function "lifting of telescopic arm And a third table listing all the combinations of allowed movements and defining coefficients of reduction of the own speeds of each of the functions according to their direction of action to reduce the linear speed of the personnel receiving basket to a desired level substantially constant in below the maximum speed obtained by adding the speeds corresponding motion functions in isolation, for example the "turret rotation" function and the "telescopic arm lift" function. The computer (10) on the aerial platform receives from a sensor (12) a continuous measurement signal of the elevation of the telescopic arm (6) according to the arrow B of FIG. 1, and a sensor (13). ) a measurement signal of a telescoping sensor in the direction of the arrow C of Figure 1. The computer (10) also receives a command from an operator acting on a control (14). The calculator (10) processes the measurements obtained from the sensors (12 and 13) and the control member (14) to calculate the linear horizontal and vertical speed components of the receiving basket (7). The computer (10) interrogates the memory (11) to extract the hydraulic fluid flow correction coefficients corresponding to the requested movements and to the rectangular coordinate position of the newly received personnel receiving basket and assigns these correction coefficients. hydraulic fluid flow rate continuously to a working register (15) containing the permissible reference values for the work to be performed using the aerial platform according to the invention. The computer (10) uses these hydraulic fluid flow correction coefficients of the working register (15) to continuously calculate the hydraulic fluid flow instructions of the actuators corresponding to the movements requested and assigns these instructions to a memory (16) of setpoint data. The computer (10) applies these instructions of the setpoint data memory (16) and acts on the control system (17) for moving the aerial platform to move the receiving basket (7) at a constant speed, thus preserving the stability of the operators embedded in the reception basket (7).

Preferably, the computer (10) acts proportionally and continuously on the hydraulic flows of the actuators generating the movements of the aerial platform according to the invention, in particular the movements referenced with respect to the axis A, and with respect to the arrows B and C of FIG. 1. The invention thus makes it possible to guarantee a constant speed of the receiving basket (7) by adjusting the hydraulic flow rates of the corresponding hydraulic movements, by measuring the telescoping of the arm (6) and the measurement continuous elevation angle of the telescopic arm (6). The measurements make it possible to determine not only the positions of the reception basket in the work area in the context of the trirectangular coordinates, but also to provide the differentials between two corresponding positions of the receiving basket, that is to say the speeds of movement of the basket of reception (7) in the work area. The control and adjustment of the hydraulic movements of the actuators of the aerial platform according to the invention are advantageously effected by means of proportional and continuous control valves. Thanks to the invention, the movements of the aerial platform according to the invention are regulated to provide a constant speed of movement of the receiving basket (7) in the working space. According to an advantageous mode of operation of the invention, for example during an upward movement of the telescopic arm and extension of the telescopic arm to a measured length, the on-board computer (10) thus calculates the hydraulic flows and the speeds motor to ensure constant vertical speed and constant horizontal speed of the personnel receiving basket (7). The horizontal and vertical speeds of movement of the receiving basket (7) are determined by calculation according to the set point imposed on the control (14) by the user, as a function of the elevation of the telescopic arm and its telescoped length. . In the case of a nacelle with telescopic arm having a turret, as described with reference to FIG. 1, the on-board computer (10) calculates the hydraulic flows and the engine speeds providing a constant horizontal speed of the receiving basket (7). personnel according to the actual length of the telescopic arm (6). The horizontal and vertical movement speeds of the receiving basket (7) are determined by calculation as a function of the actual length of the telescopic arm taking into account the set point imposed by the user to the command. The invention is also applicable to a personnel hoist having no turret and having a non-rotating base secured to the wheeled chassis. The invention can also be applied to other fields than that of the personnel lifting platform. The invention can finally be applied to the case of additional movements having an effect on a speed of movement of a basket (7) for receiving personnel, for example possibly taking into account a speed of movement of a pendulum arm. In FIG. 3, a set of several tables of coefficients established as a function of the position in rectangular coordinates of the personnel receiving basket notably comprises: a first table 101 of hydraulic fluid flow correction coefficients imposing the maintenance of a constant speed of the "turret rotation" function, a second table 102 of 25 hydraulic fluid flow correction coefficients imposing to maintain a constant speed, on the function "lifting telescopic arm", and a third table 103 listing all the combinations of allowed motions and defining coefficients of reduction of the eigenfrequencies of each of the functions according to their direction of action to reduce the linear speed of the personnel receiving basket to a desired substantially constant level below the maximum speed obtained by summing the corresponding speeds of the motion functions pr in isolation, for example the "turret rotation" function and the "telescopic arm lift" function. The first table 101 of hydraulic fluid flow correction coefficients imposing the maintenance of a constant speed of the "turret rotation" function defines decreasing hydraulic fluid flow coefficients as a function of the horizontal distance of the personnel receiving basket. to the axis A vertical rotation. The second table 102 of hydraulic fluid flow correction coefficients imposing to maintain a constant speed on the function "telescopic arm lift" defines decreasing hydraulic fluid flow coefficients as a function of the horizontal extension of the telescopic arm. The third table 103 listing all the combinations of authorized movements defines coefficients of reduction of the own speeds of each of the kinematic functions according to their direction of action to reduce the linear speed of the personnel receiving basket to a desired level substantially constant below the maximum speed obtained by adding the corresponding speeds of the motion functions taken separately, for example of the "turret rotation" function and the "telescopic arm lifting" function. With the first table 101 of hydraulic fluid flow correction coefficients, a calculation of the rotation speed of the turret to be applied is made by the management device, depending on the position of the basket in space. This calculation is made on the basis of the data: telescope output length and telescopic arm angle to horizontal from a reference speed in horizontal telescopic arm configuration and fully retracted telescope. This reference speed is generally defined by the duration of a full revolution of rotation to obtain a maximum speed of the personnel receiving basket, for example 0.5 m / s. This calculated speed of rotation of the turret is maintained and controlled by the hydraulic fluid flow setpoint assigned to this function.

Thanks to the second table 102 of hydraulic fluid flow correction coefficients, imposing to maintain a constant speed on the "telescopic arm lifting" function, a calculation of the speed of movement of the telescopic arm is carried out by the management device, in depending on the position of the basket in the space. This calculation is made on the basis of the data: telescope output length and telescopic arm angle to horizontal from a reference speed in horizontal telescopic arm configuration and fully retracted telescope. This reference speed is generally defined by the duration of a complete lifting trajectory to obtain a maximum speed of the personnel receiving basket, for example of 0.4 m / s. Starting from the maximum reference speed in the retracted telescope and in the horizontal telescopic arm, for example 0.4 m / s, and another maximum reference speed in telescope output and horizontal telescopic arm, for example also 0.4 m / s, the Management performs interpolation of the hydraulic flow coefficients between these two reference speeds as a function of the telescope output position measurement for the telescopic arm lift speeds. This speed thus calculated by interpolation of movement of the telescopic arm is maintained and controlled by the hydraulic fluid flow setpoint assigned to this function. With the third table 103 listing all the combinations of authorized movements, by imposing to maintain a constant speed of the personnel receiving basket in space, a calculation of the speed of movement of the telescopic arm is made by the management device, in function of accumulations of movements made simultaneously and according to the position of the basket. By simultaneously operating several movements such as telescopic arm lifting, telescoping, rotation of the turret and lifting of a possible pendulum arm, the linear speed of movement of the personnel receiving basket in the space can be amplified. To avoid the risk of shock or corresponding accident, while maintaining fast and compliant unit speeds, during an elevation performed by combining two or three functions, the management device applies a rate reduction coefficient on each of the functions cumulation in progress.

Each combination of a possible combination of functions corresponds to a set of reduction coefficients of these functions.

The management device according to the invention applies, for each combination of cumulative achievable out of eighty possible combinations, a set of speed reduction coefficients specific to these functions, so as to maintain a linear speed of evolution of the constant basket. .

The invention described with reference to a particular embodiment is in no way limited thereto, but on the contrary covers any modification of form and any variant embodiment within the scope of the appended claims.

Claims (10)

REVENDICATIONS1. A method of displacement management, in particular for personnel lifting platform, comprising the following steps: a) measuring the displacement of a telescopic arm; b) measuring the elevation angle of the telescopic arm; c) calculate the position in rectangular coordinates of the staff receiving basket; d) continuously control and adjust the hydraulic flows of the actuators producing the movements of the aerial platform to impose a linear speed of constant basket evolution. 2. Method of displacement management according to claim 1, in the case of a personnel lifting platform having a turret (5) allowing the telescopic arm (6) to rotate relative to the frame (1) of the aerial platform, in which calculates the position in rectangular coordinates of the personnel receiving basket, and in which the hydraulic flows of the actuators producing the turret rotation movement of the aerial platform are continuously controlled and adjusted to impose a linear speed of evolution of the constant basket. 3. A displacement management method according to claim 1 or 2, wherein the horizontal component of the movement speed of the basket (7) is kept below a predetermined threshold. 4. Method of displacement management according to claim 2, wherein the vertical component of the speed of movement of the basket (7) is kept below a predetermined threshold. 5. Movement management device, in particular for personnel lifting platform, comprising means (13) for measuring the displacement of the telescopic arm, means for measuring (12) the elevation angle of the brastelescopic, means (10) for calculating the position in rectangular coordinates of the personnel receiving basket, means (17) for continuously controlling and adjusting the hydraulic flow rates of the actuators producing the movements of the aerial platform, and means (10) for controlling the movement of the personnel hoist to impose an absolute constant speed of basket evolution. The apparatus of claim 5, wherein the means for calculating the rectangular coordinate position of the personnel receiving basket associates a telescopic arm elevation angle sensor, a telescopic arm extension sensor, and a calculator. . 7. Device according to claim 5 or 6, wherein the means for controlling and continuously adjusting the hydraulic flow rates of the actuators (8) producing the movements of the aerial platform associate a calculator knowing the position of the staff reception basket in coordinates rectangular and driving the engine speed driving the pump and / or proportional hydraulic valves, so as to obtain a linear speed of the basket below a predetermined limit. 8. Device according to claim 5 or 6, wherein the means for controlling the displacement of the personnel lifting platform to impose an absolute constant rate of basket evolution associate a first coefficient of correction of hydraulic fluid flow imposing the maintenance of a constant speed of the "turret rotation" function and a second coefficient of hydraulic fluid flow correction imposing to maintain a constant speed, on the function "telescopic arm lift" to control and continuously adjust the hydraulic flow rates of actuators (8) producing the movements of the aerial platform, so as to obtain a linear speed of the basket within a predetermined limit. 9. Device according to claim 5 or 6, wherein the means for controlling the movement of the personnel lifting platform to impose an absolute constant speed of basket evolution associate coefficients of a third table listing all the combinations of authorized movements. and defining self-speed reduction coefficients of each of the functions in accordance with their actions of reducing the linear speed of the personnel receiving basket to a substantially constant desired level. 10. Device according to claim 5, in the case of a personnel lifting platform having a turret (5) allowing the telescopic arm (6) to rotate relative to the frame (1) of the aerial platform, in which the position in rectangular coordinates of the personnel receiving basket, and in which one continuously controls and adjusts the hydraulic flows of the actuators producing the turret rotation movement of the aerial platform to impose a linear rate of change of the basket constant.