Method for controlling an aerial lift, in particular a scissor lift, and associated aerial lift

Abstract

Disclosed is a method for controlling an aerial lift, comprising a first step (101), performed when the wheels are not turning, during which a first characteristic variable of states of the aerial lift is measured, the first variable being a height of a basket of the aerial lift, and at least one second characteristic variable of states of the aerial lifts is measured, wherein the first value, together with the at least one second value measured for every second variable, forms a group of values. A second step (102) is then carried out to assess whether every group of values is situated within an authorized zone (Z1) or a prohibited zone (Z2) of a nomogram (110) associated with this group of values. During a subsequent third step (103), the ground movement of the aerial lift is authorized or not, depending on the assessment in the second step (102).

Description

[0001] TITLE: Method for controlling a lifting platform, in particular a scissor lift, and associated lifting platform

[0002] The present invention relates to a method for controlling a lifting platform, in particular a scissor lift, as well as a lifting platform implementing such a control method.

[0003] A mobile personnel lifting platform, also simply called a "lifting basket", comprises a chassis, which is mounted on wheels to allow the lifting basket to be moved on the ground, a basket - also called a basket - and a basket lifting device, which is inserted between the basket and the chassis so as to adjust the height of the basket relative to the ground. We are interested here in lifting baskets allowing the basket to be raised vertically from the chassis when the ground is horizontal. In a non-limiting manner, scissor lifting devices, telescopic lifting devices, boom lifting devices, etc. are known.

[0004] The basket, which includes a platform surrounded by a guardrail, is designed to accommodate one or more people and possibly also loads such as tools or other equipment, materials such as paint, cement, etc.

[0005] In the case of a scissor lift, the lifting device comprises bars, which are hinged in their center in a scissor-like manner, several of these scissor mechanisms being mounted one above the other by their ends, which are pivotally connected, so that the assembly formed by the articulated bars can fold and extend upwards. The lifting device also comprises at least one actuator, generally hydraulic cylinders, which operates the articulated bars to extend or retract them.

[0006] To enable the basket to be lifted, the ends of the upper bars are connected to runners designed to slide in rails provided under the platform floor, while the ends of the lower bars are connected to runners designed to slide in rails provided on the chassis. The lifting device thus enables the basket to be raised from a lowered position on the chassis to the desired working height, generally by means of one or more hydraulic cylinders, the basket then being in a raised position.

[0007] On aerial work platforms, stability is essential for safety reasons. The height of the basket, as well as the load it supports, the distribution of the load on the platform, etc., are among the elements that must be known to control this stability and ensure that the operator does not use the aerial work platform beyond safe conditions.

[0008] In particular, according to current very conservative practice, when the basket is in the raised working position, if the aerial work platform has to be moved on the ground, then the basket must first be returned to the lowered position before moving the chassis relative to the ground, and then raising the basket to its raised working position. In addition, some machines require the installation of stabilizers to raise. Moving requires raising the stabilizers, moving, then replacing the stabilizers before being able to raise again. This succession of operations requires time and energy, which affects the autonomy of aerial work platforms, particularly when the aerial work platforms are electric, which is increasingly the case.

[0009] US-2022 / 198905-A1 describes, for example, a lifting platform equipped with an optical system for analyzing the environment of the platform, so as to prevent collisions with the environment. US-2017 / 052542-A1 describes, for its part, an autonomous inspection robot comprising a camera located at the end of an arm, the robot calculating a limit speed of movement according to the environment of the robot.

[0010] It is these problems that the invention specifically aims to address by proposing a lifting platform that is easier to operate and more economical, without compromising safety.

[0011] For this purpose, the invention relates to a method for controlling a lifting platform, in which: the lifting platform comprises wheels and is configured to move on the ground by rotating the wheels, a direction of movement of the lifting platform on the ground being controlled by means of a steering of the wheels, the lifting platform optionally comprising an oscillating axle and / or a basket with an extension, in a first step, while the wheels are not rotating:

[0012] • a first quantity characteristic of states of the lifting platform is measured by means of a first measuring device, the first quantity being a height of the basket of the lifting platform relative to a lowered position of the basket, so as to obtain a first value, and

[0013] • at least one second characteristic quantity of states of the lifting platform is measured, each second quantity being different from the first quantity and being measured by means of a measuring device, so as to obtain at least one second value, the first value forming, with the at least one second value measured for each second quantity, a group of values, the at least one second characteristic quantity is chosen from:

[0014] • a mass of a load carried in the basket,

[0015] • an oscillation angle of an oscillating axle of the lifting platform,

[0016] • a coefficient of distribution of the mass of the load carried in an extension of the basket, or

[0017] • a steering angle of the wheels during a second stage, after the first stage, we evaluate:

[0018] • by means of a calculator and an abacus recorded in the calculator, each group of values ​​being associated with a respective abacus and forming coordinates of a point in this abacus, the abacus being divided into an authorization zone and a prohibition zone, which is complementary to the authorization zone,

[0019] • if the group of values ​​measured in the first stage is included in the authorization zone or in the prohibition zone of the chart, during a third stage, subsequent to the second stage, the ground movement of the lifting platform is authorized or not, by means of a controller, depending on the evaluation of the second stage.

[0020] Thanks to the invention, it is possible to allow the lifting platform to move on the ground even when the basket is higher than in the lowered position, as long as the platform is in operating conditions that do not compromise the stability of the lifting platform, which saves energy and time. The lifting platform is thus easier to operate, without compromising safety.

[0021] According to advantageous but not mandatory aspects of the invention, such a control method may incorporate one or more of the following features taken in isolation or in any technically admissible combination:

[0022] In the first step, at least two second values ​​are measured, which are respectively associated with second characteristic quantities that are different from each other, while the first value forms, with each of the two second values, two groups of values, which are each associated with a respective chart, in the second step, it is assessed whether each group of values ​​is included in the authorization zone or in the prohibition zone of the corresponding chart, and in the third step, the ground movement of the lifting platform is authorized if each group of values ​​is located in the authorization zone of the corresponding chart.

[0023] One of the charts used in the second step is a conditional chart, which includes a first version and a second version, with either the first version or the second version being activated depending on the environment and / or a configuration of the aerial work platform.

[0024] The first version is activated when the aerial work platform is located on a ground forming a slab, the slab having a leveled and compacted surface, while the second version is activated when the aerial work platform is located on a ground not forming a slab, while during the second step, the calculator evaluates whether the group of values ​​associated with the conditional chart is included in the authorization zone or in the prohibition zone of the activated version of the conditional chart.

[0025] In the authorization zone of the second version of the conditional chart, each point is uniquely associated with a maximum ground speed instruction for the lifting platform, whereas during the third stage, the movement authorization includes the maximum movement speed instruction.

[0026] The maximum travel speed setpoint depends on the measured value of the first quantity.

[0027] Each group of values ​​includes, in addition to the first value, a single second value, the abacus associated with each group of values ​​forming, in graphic representation, a two-dimensional space.

[0028] The invention also relates to a lifting platform, in particular a scissor lift, comprising: a chassis supported by wheels, the lifting platform being configured to move on the ground by rotating the wheels, a basket, configured to receive an on-board load, a lifting device, which is interposed between the basket and the chassis, so that a height of the basket relative to a lowered position of the basket is adjustable, a first measuring device, configured to measure a first characteristic quantity of states of the lifting platform, the first characteristic quantity being the height of the basket, at least one second measuring device, each second measuring device being configured to measure a second characteristic quantity of a state of the lifting platform, the first and second characteristic quantities being different from each other, a calculator and an abacus recorded in the calculator,wherein the nacelle is configured to implement the control method according to any one of the preceding claims.,

[0029] Advantageously: the lifting platform comprises an axle which is oscillating, and / or the basket comprises an extension.

[0030] The invention will be better understood, and other advantages thereof will appear more clearly in the light of the following description of several embodiments of a method for controlling a lifting platform and of a lifting platform, in accordance with its principle, given solely by way of example and with reference to the appended drawings, in which:

[0031] - [Fig 1] Figure 1 is a perspective view of a lifting platform according to a first embodiment of the invention;

[0032] - [Fig 2] Figure 2 represents respectively, on four inserts a), b), c) and d), the lifting platform of Figure 1 in four different configurations and seen from the side;

[0033] - [Fig 3] Figure 3 is a front view of the lifting platform of Figure 1, shown in another configuration;

[0034] - [Fig 4] figure 4 represents respectively, on two inserts a) and b), a synoptic diagram illustrating a method of controlling the lifting platform of figure 1, and an example of an abacus used by this method;

[0035] - [Fig 5] Figure 5 represents respectively, on two inserts a) and b), lifting cradles in accordance with other embodiments of the invention;

[0036] - [Fig 6] Figure 6 represents respectively, on two inserts a) and b), charts used in control methods in accordance with other embodiments of the invention, and

[0037] - [Fig 7] Figure 7 represents respectively, on two inserts a) and b), charts used in control methods in accordance with other embodiments of the invention.

[0038] A lifting platform is shown in Figure 1. In the example illustrated, the lifting platform is a scissor lift 10. In a variant not shown, the lifting platform is of another type, for example a telescopic platform, the principles of the invention described with reference to the scissor lift 10 being transposable to other types of lifting platform. The scissor lift 10 comprising a chassis 12 capable of resting and moving on a ground S by connecting members, generally wheels 14. The scissor lift 10 here comprises two axles 15, which are supported by the wheels 14. A single axle 15 is shown in Figure 3. The wheels 14 define a preferred direction of movement of the chassis 12 and, by extension, of the scissor lift 10.

[0039] The nacelle 10 also comprises a basket 16, and a device 18 for lifting the basket 16. In the illustrated example, the basket 16 comprises a platform 17A, a guardrail 17B, and a controller 17C. The controller 17C is configured to transmit information to a user, and to receive control commands from this user. According to non-limiting examples, the controller 17C is a human-machine interface intended for a user located on the platform 17A. For example, the controller 17C comprises buttons and / or control levers, one or more indicator lights or lights, a display screen, possibly a touch screen, one or more audible warning devices.

[0040] The lifting device 18 comprises a set of articulated bars 20 supporting the basket 16, such that the elevation of the basket 16 relative to the chassis 12 is variable and controlled by the set of bars 20. The lifting device 18 also comprises an actuator 22, here a hydraulic cylinder, which actuates the bars 80 to control a height H of the platform 16 relative to the chassis 12, and by extension relative to the ground S on which the scissor lift 10 moves. The actuator 22 is for example controlled using the controller 17C, by a user located on the platform 17A.

[0041] The chassis 12 defines a mean plane P12, which is parallel to the ground S. The lifting device 18 defines an elevation axis Z18 which is perpendicular to the mean plane P12. The elevation axis Z18 is thus vertical when the ground S is horizontal. X12 is a longitudinal axis of the chassis 12, the longitudinal axis X12 being oriented parallel to the direction of advance of the chassis 4. The longitudinal axis X12 is parallel to the horizontal plane P4 and perpendicular to the vertical axis Z8. A transverse axis Y12 of the chassis 12 is also defined, which is oriented such that the longitudinal axis X12, the transverse axis Y12 and the elevation axis Z18 together form a direct orthogonal reference frame.

[0042] A movement “on the ground S” of the scissor lift 10 corresponds to a movement of the chassis 12 relative to the ground S, this movement being caused by the rotation of the wheels 14. When the wheels 14 do not turn, the chassis 12 is considered to be stationary relative to the ground S.

[0043] Some of the wheels 14, for example the wheels 14 of a front axle of the scissor lift 10, are steerable, so as to direct the movement of the scissor lift 10 on the ground S. For example, the wheels 14 of one of the axles 15 are steerable. A steering angle a14 is defined as being an angle between the steerable wheels 14 and the longitudinal axis X12. When the wheels 14 are aligned with the longitudinal axis X12, the steering angle a14 is zero. When the steering angle a14 is zero and the wheels 14 turn, the chassis 12 moves substantially in a straight line - the ground S being considered as flat. When the wheels 14 are steered, in other words when the steering angle a14 is non-zero, then if the wheels 14 turn, the chassis 12 moves substantially in an arc of a circle on the ground.The scissor lift 10 advantageously comprises a device for measuring the steering angle a14, for example an angular sensor mounted on the axle 15 supported by the steerable rollers 14. The angular sensor is not shown.

[0044] When the chassis 12 is stationary relative to the ground S, by extension the scissor lift 10 is also said to be “stationary relative to the ground S”, but other movements of the scissor lift 10 generally remain possible, for example it remains possible to raise or lower the basket 16, and / or to modify the steering angle a14 of the wheels 14, etc., when these movements are not prohibited for another reason, for example for safety reasons.

[0045] In the four inserts a) to d) of figure 2, the scissor lift 10 is shown in four different configurations, which correspond to four different heights H of the basket 16.

[0046] In insert a), the scissor lift 10 is shown in a lowered configuration, which corresponds to a minimum height Hmin of the basket 16, in which the lifting device 18 is fully folded. The basket 16 is then in a minimum elevation position called the lowered position.

[0047] In insert d), the scissor lift 10 is shown in a raised configuration, in which the lifting device 18 is fully extended, while remaining in normal conditions of use. The height H of the basket 16 is equal to a maximum height Hmax. In the raised configuration, the basket 16 is then in a maximum elevation position.

[0048] It is understood that the minimum heights Hmin and maximum heights Hmax are two extreme values ​​of the height H of the basket 16, which are notably linked to the design of the parts, notably to the geometry of the lifting device 18. During normal use of the scissor lift 10, the user adjusts the height H of the basket 16 between these two extreme heights Hmin and Hmax.

[0049] In insert b) of figure 2, the basket 16 is shown in a first intermediate position between the lowered position and the maximum elevation position, the scissor lift 10 being in a first intermediate configuration, in which the height H of the basket 16 is equal to a first height threshold H1, which is strictly less than the maximum height Hmax.

[0050] In insert c) of figure 2, the scissor lift 10 is shown in a second intermediate configuration, in which the height H of the basket 16 is equal to a second height threshold H2, which is strictly less than the maximum height Hmax and strictly greater than the first height threshold H1.

[0051] The scissor lift 10 also comprises a first measuring device, which is configured to measure the height H of the basket 16. The first measuring device is not shown. The first measuring device includes for example an angle sensor, which measures an angle between two successive bars of the busbar 20. Alternatively, the first elevation device includes a sensor of a stroke of the actuator 22. The height H, measured by the first measuring device, is a first quantity which characterizes a state of the scissor lift 10, in other words the height H is a first quantity characteristic of states of the scissor lift 10.

[0052] Still with reference to insert c) of Figure 2, the basket 16 is shown as supporting a load M1, which has a given mass. The load M1 is said to be loaded in the basket 16. The load M1 comprises, for example, one or more people present on the platform 17A, and / or tools, materials, etc., transported on the platform 17A.

[0053] The scissor lift 10 comprises a measuring device configured to measure the mass of the load M1 carried in the basket 16. The device for measuring the mass M1 carried is not shown. According to a non-limiting example, the device for measuring the mass of the load M1 carried comprises load sensors integrated into the joints of the busbar 20, as described in the published application FR-3 105 202.

[0054] It is understood that the higher the mass of the load M1 and the higher the height H of the basket 16, then in the event of untimely movement of the scissor lift 10 on the ground S, the risks of the scissor lift 10 tipping over increase.

[0055] In Figure 2, the ground S is assumed to be flat, but is not horizontal, the ground S having a slope angle. It is understood that the elevation axis H18 is not perfectly vertical. In Figure 3, the scissor lift 10 is shown on a ground S which is not flat. To compensate for the flatness defects of the ground S, one of the axles of the scissor lift 10, here the axle 15 shown in Figure 3, is “oscillating”, that is to say that this oscillating axle 15 is pivoting, relative to the rest of the chassis 12, around an axis parallel to the longitudinal axis X12. The oscillating axle 15 thus serves to compensate, at least partially, for a flatness defect of the ground S, so that the elevation axis Z18 is kept substantially vertical. An oscillation angle a15 is defined as an angle between an axis A15 of the oscillating axle 15 and the mean plane P12. When the scissor lift 10 moves on a flat ground S, the oscillation angle a15 is zero.The scissor lift 10 comprises a measuring device configured to measure the oscillation angle a15, for example an angle sensor mounted on the chassis 12. The device for measuring the oscillation angle a15 is not shown.

[0056] It is understood that depending on the situation, the scissor lift 10 is called upon to operate on a ground S having various levels of flatness, hardness, etc. The ground S is said to form a “slab” - or slab in English - when the ground S has a leveled and compacted surface. By “leveled”, we mean a substantially flat and horizontal surface. By “compacted surface”, we mean a surface considered to be non-deformable during the passage of the scissor lift 10, in particular no ruts are formed when the wheels 14 pass over it. A slab corresponds for example to the concreted ground S of a logistics warehouse.

[0057] The mass of the load M1 carried in the basket 16, the oscillation angle a15 of the oscillating axle 15 of the scissor lift 10, or the steering angle a14 of the wheels 14, are all examples of quantities characteristic of states of the scissor lift 10, these characteristic quantities being called “second quantities”. Each of the second quantities is measured by means of a respective measuring device.

[0058] It is understood that the higher the height H of the basket 16, and the higher one or more of the second quantities, the greater the risks of the scissor lift 10 tipping over in the event of uncontrolled movement of the scissor lift 10 relative to the ground 1. A method for controlling the scissor lift 10, described below with reference to FIG. 4, is implemented to reduce this risk.

[0059] With reference to insert a) of Figure 4, the control method comprises a first step 101, during which, while the wheels 14 are not rotating, the height H of the basket 16 is measured so as to obtain a first value. In other words, while the chassis 12 is stationary relative to the ground S, the first characteristic quantity of the scissor lift 10 is measured.

[0060] Still during the first step 101, at least one second characteristic quantity of states of the scissor lift 10 is also measured, each second quantity being different from the first quantity and being measured by means of a respective measuring device, so as to obtain at least one second value. In other words, in the illustrated example, at least one of the quantities among the mass of the load M1 on board the basket 16, the oscillation angle a15 of the oscillating axle 15, and the steering angle a14 of the wheels is measured, while the chassis 12 is stationary relative to the ground S. The scissor lift 10 advantageously comprises a computer 17D, which comprises a memory - not shown -, so that the computer 17D is configured to record the values ​​of the measurements carried out during the first step 101. The computer 17D is for example integrated into the controller 17C.

[0061] The 17D calculator is also configured to record one or more charts.

[0062] The first value forms, together with one or more of the second values, one or more groups of values. Each group of values ​​is associated with a respective abacus and forms coordinates of a point in this abacus. In the present case, the first value is a measurement of the height H of the basket 16, the second values ​​being measurements of the mass of the load M1, the steering angle a14 or the oscillation angle a15. It is therefore theoretically possible to form three groups of values ​​comprising a single second value, in particular the groups of values ​​{M1,H}, {M1,a14} and {M1,a15}, three groups of values ​​comprising two second values: {M1,H,a14}, {M1,H,a15} and {M1,a14,a15}, and a single group of values ​​comprising three second values: {M1,H,a14,a15}. However, not all value groups are necessarily useful.

[0063] According to a preferred embodiment, each group of values ​​comprises, in addition to the first value, a single second value, the abacus associated with each group of values ​​forming, in graphic representation, a two-dimensional space. A first example of such an abacus, referenced 110, is graphically represented in insert b) of FIG. 4. The abacus 110 is here associated with the mass of the load M1 and the height H. In other words, the group of values ​​{M1, H} forms coordinates of a point in this abacus 110, which defines, in graphic representation, a two-dimensional space that is easy to represent and imagine. For example, the abacus 110 and the point corresponding to the associated group of values ​​are displayed on the controller 17C, for the attention of the user present on the basket 16. The graphic representation of the abacus 110 is not limiting.

[0064] The abacus 110 is divided into an authorization zone Z1 and a prohibition zone Z2, which is complementary to the authorization zone Z1. The authorization zone Z1 and the prohibition zone Z2 are separated by a boundary F110, which is continuous. In other words, the boundary F110 is characteristic of the abacus 110 and divides the space of the abacus 110 into two complementary zones, the authorization zone Z1 and the prohibition zone Z2.

[0065] More generally, the control method comprises a second step 102, which is subsequent to the first step 101 and during which it is evaluated, by means of the computer 17D and the chart 110 recorded in the computer 17D, whether the group of values ​​measured in the first step 101 is included in the authorization zone Z1 or in the prohibition zone Z2 of the chart 110. The control method also comprises a third step 103, which is subsequent to the second step 102 and during which, by means of a controller - here by means of the controller 17C -, the movement on the ground of the scissor lift 10 is authorized or not depending on the evaluation of the second step 102. If, in the second step 102, the group of values ​​is located in the authorization zone Z1, then in the third step 103 the movement on the ground S of the scissor lift 10 is authorized.“Ground movement authorization” does not mean that the scissor lift 10 will automatically begin to move on the ground; it means that if the user commands the scissor lift 10 to move, for example to the controller area 17C, then the user's command is accepted and executed.

[0066] If, in the second step 102, the value group is located in the prohibition zone Z2, then in the third step 103 the ground movement S of the scissor lift 10 is prohibited. In other words, even if the user commands the movement of the scissor lift 10, then the user's command is not executed.

[0067] In the example illustrated, the value group associated with the abacus 110 includes the height H and the mass of the on-board load M1. It is understood that when the height H is reduced, for example equal to the minimum height Hmin, the movement on the ground of the scissor lift 10 must be possible whatever the on-board load M1 - in compliance with the specifications of the scissor lift 10 of course - Thus, in the graphic representation of the abacus 110, the authorization zone Z1 includes the origin of the abacus 110.

[0068] Thus, during the third step 103, the controller 17C only gives authorization for movement on the ground S of the scissor lift S if the load M1 is sufficiently reduced with respect to the height H, and vice versa, that is to say if the height H is sufficiently reduced with respect to the load M1. The control method according to the invention thus makes it possible to move the scissor lift 10 without risk of tipping, that is to say the safety of people and equipment is maintained, and this without having to return the basket 16 to the lowered position, which saves time and energy.

[0069] As illustrated in Figure 4 b), the authorization zone Z1 and the prohibition zone Z2 are advantageously divided according to predetermined thresholds of the first and second values ​​considered, in order to facilitate the understanding of the chart 110, in particular when the user is in a complex environment, for example when the user is located on the basket 10 and the scissor lift 10 is moving on a construction site, the environment of which is not well controlled. The boundary F110 here has a staircase shape. Each second quantity, M1, a14 or a15, evolves between a minimum value LO and a nominal value Lmax, which are defined by design of the scissor lift 10.For each second quantity, we also define a first threshold L1, which is a predetermined threshold strictly lower than the nominal value Lmax, and strictly higher than the minimum value LO, as well as a second threshold L2, which is strictly lower than the first threshold L1 and strictly higher than the minimum value LO.

[0070] When, in the first step 101, the first value H is lower than the first height threshold H1, then, in the second step 102, as long as the second value is lower than a nominal value Lmax associated with this second characteristic quantity, then the associated group of values ​​is included in the authorization zone Z1 of the corresponding chart.

[0071] When, in the first step 101, the first value H is between the first height threshold H1 and a second height threshold H2, the second height threshold being intermediate between the first height threshold H1 and the maximum height Hmax of the basket 16, then, in the second step 102, as long as the second value is lower than the first threshold L1, then the group of values ​​is included in the authorization zone Z1.

[0072] When, in the first step 101, the first value H is between the second height threshold H2 and the maximum height Hmax of the basket, then, as long as the second value is lower than the second threshold L2, then, in the second step 102, the group of values ​​is included in the authorization zone Z1.

[0073] The example illustrated by means of the abacus 110, associated with the values ​​of height H and mass of load M1 on board, in other words associated with the group of values ​​{H,M1}, can be transposed to the other groups of values, in particular here to the groups of values ​​{M1 ,a14} and {M1 ,a15}.

[0074] The situation of the abacus 110, defined by two thresholds associated with the first quantity and by two thresholds associated with the second quantity, is nevertheless preferred, because it is easy for the user to understand.

[0075] Preferably, the safety criteria associated with several groups of values ​​are considered simultaneously. Thus, during the first step 101, at least two second values ​​M1 / a14 / a15 are measured, which are respectively associated with second characteristic quantities different from each other.

[0076] The first value H forms, with each of the two second values ​​M1 / a14 / a15, at least two groups of values, which are each associated with a respective chart. The at least two groups of values ​​are therefore chosen here from the three groups of values ​​{M1,H}, {M1,a14} and {M1,a15}. Three charts are thus provided. According to examples, these three charts, not shown, are similar to chart 110, in that the characteristic lines separating the authorization zones from the prohibition zones have a staircase shape. In other words, for each chart, two thresholds are defined for the first quantity, and two thresholds are defined for each second quantity. Advantageously, the thresholds defined for the first quantity, in other words the thresholds H1 and H2 defined for the height H, are identical for each chart, so as to standardize the height criterion between each chart and to facilitate understanding by the user.

[0077] During the second step 102, it is evaluated whether each group of values ​​is included in the authorization zone Z1 or in the prohibition zone Z2 of the corresponding chart. During the third step 103, the ground movement S of the scissor lift 10 is authorized if each group of values ​​is located in the authorization zone Z1 of the corresponding chart. In other words, for each of the second measured values, if at least one of the associated groups of values ​​is located in the prohibition zone Z2 of the chart corresponding to this group of values, then in the third step, the ground movement S of the scissor lift 10 is prohibited. The safety of the scissor lift 10 is thus improved, because it takes into account multiple criteria, each associated with states of the scissor lift 10.

[0078] Alternative embodiments of the invention are illustrated in Figures 5 to 7. In the alternative embodiments of the invention, elements similar to those of the other embodiments bear the same references and function in the same way. In the following, the differences between each embodiment and the previous one(s) are mainly described.

[0079] An alternative lifting platform, here a scissor lift 11, is shown in Figure 5. The scissor lift 11 differs from the scissor lift 10 described previously in that the platform 17A is extendable, that is to say that the basket 16 comprises an extension 19, which can be deployed or stowed, according to the needs of the user. The platform 17A is generally aligned, along the elevation axis Z18, with the lifting device 18.

[0080] In insert a) of figure 5, the extension 19 in a so-called stowed position, the basket 16 being in a stowed configuration. A first load M' is shown, placed on the platform 17A.

[0081] On insert b), the extension 19 is in the deployed position, that is to say that the extension 19 protrudes from the platform 17A and extends the platform 17A, so as to increase a loading surface of the basket 16. The basket 16 is then in a so-called deployed configuration. A second load M” and a third load M'” are shown, the second load M” being placed on the platform 17A, while the third load M'” is placed on the extension 19. In the example illustrated, it is considered that the cumulative mass of the second load M” and the third load M'” is equal to a mass of the first load M'. Thus the second load M” is generally aligned, along the elevation axis Z18, with the lifting device 18, while the third load M'” is not aligned with the lifting device 18. It is understood that the heavier the third load M'” is, the less stable the scissor lift 11 is.

[0082] C19 is a coefficient for distributing the mass of the load carried in the basket 16. According to a non-limiting example, the coefficient C19 is equal to a ratio between the mass of the third load M'”, located on the extension 19, on the total mass of the loads located on the basket 16, i.e. here the sum of the second load M” and third load M'“. By way of illustration, if the mass of the third load M'” is equal to the mass of the second load M”, then the coefficient C19 is equal to 1 / (1 +1 ) = 1 / 2, i.e. 0.5. If the mass of the third load M'” is four times greater than the mass of the second load M”, then the coefficient C19 is equal to 1 / (4+1 ) = 1 / 5, i.e. 0.2. Other equivalent definitions of the coefficient C19 are of course possible. The coefficient C19 thus characterizes the distribution, between the platform 17A and the extension 19, of the total mass loaded in the basket 16.

[0083] The scissor lift 11 comprises a measuring device configured to measure the coefficient C19. Advantageously, the measuring device configured to measure the coefficient C19 is the same as the measuring device used to measure the mass of the total load carried in the basket 16. The coefficient C19 is another example of a second characteristic quantity of states of the scissor lift 11.

[0084] The control method described above is implemented using the coefficient C19, i.e. in the first step 101, the coefficient C19 is used to form, with the first quantity and possibly with one or more other second quantities - a group of values. The second step 102 and the third step 103 are implemented as described above.

[0085] Two alternative charts, referenced 1 11 and 120, are shown in Figure 6, respectively in inserts a) and b).

[0086] In insert a), the abacus 111 is characterized by a boundary F111. The abacus 110, described previously with reference to figure 4b), is defined by two thresholds of the first quantity and by two thresholds of the second quantity, namely the first height threshold H1, the second height threshold H2, the first threshold L1 and the second threshold L2. Of course, the number of thresholds associated with the first quantity or with each second quantity can be adjusted, as required. It is understood that the more the number of thresholds increases, the more the size of the staircase steps of the characteristic curve is reduced, until the boundary F111 becomes a smooth curve, as shown in insert a) of figure 6.

[0087] In the example illustrated in Figure 6b), the abacus 120 is a three-dimensional abacus, that is to say associated with a group of values ​​comprising the first quantity and two second quantities, here the mass of the on-board load M1 and the steering angle a14. The three-dimensional space of the abacus 120 is divided in two by a boundary F120 so as to separate the authorization zone Z1 from the prohibition zone Z2. The boundary F120 is here a continuous surface.

[0088] It is understood that when the steering angle a14 is zero, the fact that the group of values ​​is located in the authorization zone Z1 or in the prohibition zone Z2 depends only on the first quantity H and the second non-zero quantity, here the load M1. We thus find ourselves in the conditions of the abacus 111, illustrated in figure 6a). In other words, on the abacus 120 of figure 6b), the intersection between the boundary F120 and the plane formed by the two axes H and M1 corresponds to the boundary F11 1 of the abacus 111 of figure 6a).

[0089] More generally, we understand that whatever the number of values ​​forming a group of values, this group of values ​​forms coordinates of a point in a space of identical dimension. It is therefore possible to define an abacus associated with this group of values, the abacus being defined in a space whose dimension is equal to the number of graders of the group of values.

[0090] That said, since the graphical representation of such a space is impossible beyond three, rather than having a single abacus with more than three dimensions, it is preferable to have several two-dimensional abacus, their graphical representation - particularly on a screen of the 17C controller - being easy and intuitive to understand.

[0091] Another aspect of the invention is described with reference to Figure 7. An abacus 130, called a “conditional abacus”, is shown in Figure 7. The conditional abacus 130 includes a first version 130A, and a second version 130B, one or the other of the first version 130A or the second version 130B being activated depending on the environment of the scissor lift 10 or 11.

[0092] For example, the first version 130A is activated when the scissor lift is located on a floor S forming a slab, for example in a warehouse, while the second version 130B is activated when the scissor lift is located on a floor S not forming a slab, for example on an outdoor construction site. More generally, when the scissor lift 10 is located elsewhere than on a floor forming a slab, the scissor lift is said to be in “all-terrain” mode. Preferably, when the scissor lift 10 is required to operate on a floor S not forming a slab, the scissor lift 10 comprises an oscillating axle.

[0093] During the second step 102 of the control method, the computer 17D evaluates whether the group of values ​​associated with the conditional chart 130 is included in the authorization zone Z1 or in the prohibition zone Z2 of the activated version - 130A or 130B - of the conditional chart 130.

[0094] Thus, if the scissor lift 10 is located on a slab, then in the second step 102 of the control method, the computer 17D evaluates whether the group of values ​​associated with the conditional chart 130 is included in the authorization zone Z1 or in the prohibition zone Z2 of the first version 130A of the conditional chart 130. If the scissor lift 10 is located elsewhere than on a slab, then in the second step 102 of the control method, the computer 17D evaluates whether the group of values ​​associated with the conditional chart 130 is included in the authorization zone Z1 or in the prohibition zone Z2 of the second version 130B of the conditional chart 130.

[0095] In the example of Figure 7a), the first version 130A of the conditional abacus 130 defines a boundary F130A, which separates the authorization zones Z1 and prohibition zones Z2 associated with the first version 130A of the conditional abacus 130.

[0096] In the example of figure 7b), the second version 130B of the conditional abacus 130 defines a boundary F130B, which separates the authorization zones Z1 and prohibition zones Z2 associated with the second version 130B of the conditional abacus 130. For comparison, the boundary F130A of the first version 130A is also reported, in dotted lines, on the second version 130B of the abacus 130.

[0097] It is understood that when the scissor lift 10 is located on a slab, the risks of the scissor lift 10 overturning are reduced than when the scissor lift 10 is located elsewhere than on a slab. In the example illustrated, this is reflected in the fact that the authorization zone Z1 of the second version 130B has a reduced size compared to the authorization zone Z1 of the first version 130A. In other words, the movement authorization criteria are stricter when the scissor lift 10 is in off-road mode compared to the situation where the scissor lift 10 is located on a slab.

[0098] Advantageously, in the authorization zone Z1 of the second version 130B of the conditional chart 130, each point is uniquely associated with a maximum speed setpoint for movement of the scissor lift 10 relative to the ground S. By unique, it is meant that each point is associated with a single speed setpoint. The speed setpoints are for example recorded in a table of numbers, which is previously recorded in the computer 17D. In the example of figure 7b), a point P1 is materialized in the authorization zone Z1 of the second version 130B of the conditional chart 130. This point therefore corresponds to a group of measured values ​​characterizing states of the scissor lift 10, here the values ​​associated with the quantities {H,M1}. The point P1 is thus associated with a speed setpoint.According to non-limiting examples, the speed instruction is given as an absolute value, for example expressed in km / h, or as a relative value, for example as a percentage of a maximum speed of the scissor lift 10.

[0099] During the third step 103 of the control method, the movement authorization given by the controller includes the maximum movement speed instruction. In other words, if the user requests, by means of the controller 17C, the movement of the scissor lift 10, and if the controller 17C gives authorization to move the scissor lift on the ground, then the movement speed is limited by the maximum speed instruction given by the controller 17C.

[0100] Advantageously, the maximum movement speed setpoint depends on the measured value of the first quantity H.

[0101] In the example described above, one or the other of the first version 130A or the second version 130B of the abacus 130 is activated depending on whether the scissor lift 10 / 11 is operating in “all-terrain” mode or not. According to yet another variant, one or the other of the first version 130A or the second version 130B of the abacus 130 is activated depending on whether the scissor lift 10 / 11 is operating inside a building or outside a building, the risks of wind being higher outside the building than inside. According to a variant not illustrated, one or the other of the first version 130A or the second version 130B of the abacus 130 is activated depending on the number of people present on the platform 17A.

[0102] According to a variant not illustrated, one or the other of the first version 130A or the second version 130B of the abacus 130 is activated depending on a configuration of the scissor lift 10 / 11, for example depending on whether the scissor lift is equipped with an oscillating axle 15, or whether the scissor lift is equipped with an extension 19 of the platform 17A.

[0103] The embodiments and variations mentioned above can be combined with each other to generate new embodiments of the invention.

Claims

CLAIMS 1. A method for controlling a lifting platform (10; 11), wherein: the lifting platform (10; 11) comprises wheels (14) and is configured to move on the ground (S) by rotating the wheels (14), a direction of movement of the lifting platform (10; 11) on the ground (S) being controlled by means of a steering of the wheels (14), the lifting platform optionally comprising an oscillating axle (15) and / or a basket (16) with an extension (19), during a first step (101), while the wheels (14) are not rotating: • a first quantity characteristic of states of the lifting platform (10; 11) is measured by means of a first measuring device, the first quantity being a height (H) of the basket (16) of the lifting platform (10; 11) relative to a lowered position of the basket (16), so as to obtain a first value, and • at least one second characteristic quantity (M1, a14, a15, C19) of states of the lifting platform (10; 11) is measured, each second quantity being different from the first quantity and being measured by means of a measuring device, so as to obtain at least one second value, the at least one second characteristic quantity is chosen from: • a mass of a load (M1) carried in the basket (16), • an oscillation angle (a15) of an oscillating axle (15) of the lifting platform (10; 11), • a coefficient (C19) of distribution of the mass of the load (M1) carried in an extension (19) of the basket (16), or a steering angle (a14) of the wheels (14), the first value forming, with the at least one second value measured for each second quantity, a group of values, during a second step (102), subsequent to the first step (101), we evaluate: • by means of a calculator (17D) and an abacus (110; 11 1; 120; 130) recorded in the calculator (17D), each group of values ​​being associated with a respective abacus and forming coordinates of a point in this abacus, the abacus being divided into an authorization zone (Z1) and a prohibition zone (Z2), which is complementary to the authorization zone (Z1), • if the group of values ​​measured in the first step (101) is included in the authorization zone (Z1) or in the prohibition zone (Z2) of the chart (110; 111; 120; 130), during a third step (103), subsequent to the second step (102), the ground movement (S) of the lifting platform (10; 11) is authorized or not, by means of a controller (17C), depending on the evaluation of the second step (102).

2. Control method according to claim 1, wherein: during the first step (101), at least two second values ​​are measured, which are respectively associated with second characteristic quantities (M1, a14, a15, C19) different from one another, the first value forms, with each of the two second values, two groups of values, which are each associated with a respective chart (110; 111; 120; 130), during the second step (102), it is evaluated whether each group of values ​​is included in the authorization zone (Z1) or in the prohibition zone (Z2) of the corresponding chart, during the third step (103), the ground movement (S) of the lifting platform is authorized if each group of values ​​is located in the authorization zone (Z1) of the corresponding chart.

3. Control method according to any one of claims 1 or 2, wherein: one of the charts used during the second step (102) is a conditional chart (130), which includes a first version (130A) and a second version (130B), one or the other of the first version (130A) or the second version (130B) being activated depending on the environment and / or a configuration of the lifting platform (10; 11).

4. Control method according to claim 3, wherein: the first version (130A) is activated when the lifting platform (10; 11) is located on a ground (S) forming a slab, the slab having a leveled and compacted surface, while the second version (130B) is activated when the lifting platform is located on a ground not forming a slab; during the second step (102), the calculator (17D) evaluates whether the group of values ​​associated with the conditional chart (130) is included in the zone authorization zone (Z1) or in the prohibition zone (Z2) of the activated version of the conditional abacus.

5. Control method according to any one of claims 3 or 4, in which: in the authorization zone (Z1) of the second version (130B) of the conditional chart (130), each point (P1) is uniquely associated with a maximum ground travel speed setpoint (S) of the lifting platform (10; 11), during the third step (103), the travel authorization includes the maximum travel speed setpoint.

6. Control method according to claim 5, in which: the maximum movement speed setpoint depends on the measured value of the first quantity (H).

7. Control method according to any one of claims 1 to 6, in which: each group of values ​​comprises, in addition to the first value (H), a single second value (M1, a14, a15, C19), the abacus (110; 11 1; 130) associated with each group of values ​​forming, in graphic representation, a two-dimensional space.

8. Control method according to claim 7, wherein, for each group of values: when, in the first step (101), the first value (H) is less than a first height threshold (H1), the first height threshold being strictly less than a maximum height (Hmax) of the basket (16), then, in the second step (102), as long as the second value (M1, a14, a15, C19) is less than a nominal value (Lmax) associated with this second characteristic quantity, then the group of values ​​is included in the authorization zone (Z1) of the associated chart (110; 111; 130), when, in the first step (101), the first value is between the first height threshold (H1) and a second height threshold (H2), the second height threshold being intermediate between the first height threshold (H1) and the maximum height (Hmax) of the basket (16), then, in the second step (102), as long as the second value is less than a first predetermined threshold (L1), the first predetermined threshold being strictly lower than the nominal value (Lmax) associated with this second characteristic quantity, then the group of values ​​is included in the authorization zone (Z1), when, at the first step (101), the first value is between the second height threshold (H2) and the maximum height (Hmax) of the basket (16), then, as long as the second value is lower than a second predetermined threshold (L2), the second predetermined threshold being strictly lower than the first predetermined threshold (L1), then, at the second step (102), the group of values ​​is included in the authorization zone (Z1).

9. Lifting platform (10; 11), in particular a scissor lift, comprising: a chassis (12) supported by wheels (14), the lifting platform being configured to move on the ground (S) by rotating the wheels, a basket (16), configured to receive an on-board load (M1), a lifting device (18), which is interposed between the basket (16) and the chassis, so that a height (H) of the basket (16) relative to a lowered position of the basket (16) is adjustable, a first measuring device, configured to measure a first characteristic quantity of states of the lifting platform (10; 11), the first characteristic quantity being the height (H) of the basket (16), at least one second measuring device, each second measuring device being configured to measure a second characteristic quantity (M1, a14, a15, C19) of a state of the lifting platform (10 ;11), the first and second characteristic quantities being different from each other, a calculator (17D) and an abacus (110; 111; 120; 130) recorded in the calculator (17D), in which: the nacelle is configured to implement the control method according to any one of claims 1 to 8.; 10. Lifting platform (10; 11) according to claim 9, wherein: the lifting platform comprises an axle (15) which is oscillating, and / or the basket (16) comprises an extension (19).

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