Alert method for an aerial lift, in particular an articulated lift, and associated aerial lift
Patent Information
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- HAULOTTE GROUP
- Filing Date
- 2024-08-13
- Publication Date
- 2026-06-24
Smart Images
Figure EP2024072794_20022025_PF_FP_ABST
Abstract
Description
[0001] TITLE: Alert method for a lifting platform, in particular an articulated platform, and associated lifting platform
[0002] The present invention relates to an alert method for a lifting platform, in particular an articulated platform, as well as a lifting platform configured to implement such an alert method.
[0003] A lifting platform refers to a mobile personnel lifting platform. Several types of lifting platforms are known, including articulated platforms, mast platforms, telescopic platforms, scissor lifts, etc. A lifting platform - also simply called a "platform" - comprises a chassis, which is mounted on wheels to allow the platform to move on the ground, a basket, and a lifting device, which is interposed between the basket and the chassis so as to adjust the height of the basket relative to the chassis. The lifting device generally comprises at least one actuator, for example a hydraulic cylinder, which is arranged to extend or retract the lifting device, raising or lowering the basket. The basket, integral with the chassis, thus moves relative to the ground when the chassis moves relative to the ground, and also moves vertically under the effect of the lifting device.
[0004] In the case of an articulated boom lift, the lifting device is a lifting arm, which is articulated relative to the chassis and often includes a telescopic portion. The basket comprises a platform surrounded by a guardrail and is designed to accommodate one or more people and possibly also loads such as tools and / or materials.
[0005] The aerial work platform is used in various configurations. For example, the aerial work platform is generally transported in a folded configuration, by truck, to an unloading location close to a final location of use. Then, during an approach phase, the aerial work platform is moved by rolling on the ground from the unloading location to the location of use, the aerial work platform generally being in a folded configuration. Generally, during the approach phase, the articulated aerial work platform travels at a moderate speed, with the rolling speed of the articulated aerial work platform typically being limited to a "walking" speed, of the order of 5 km / h. Once the aerial work platform has arrived at the location of use, the lifting device is deployed to the desired height for working at height.
[0006] If necessary, the aerial work platform can still be driven with the lifting device in the raised position, but at a reduced speed, for example less than 1 km / h, to reduce the risk of accidents when the operator is at height. The reduced speed is generally defined by safety standards.
[0007] WO-2010 / 037999-A1 describes, for example, a method of alerting in the event of a collision of the basket with an external obstacle.
[0008] When the articulated boom lift rolls on uneven ground, the operator in the basket may experience accelerations such that the operator risks losing balance, potentially resulting in injury, or even being ejected from the basket. Similarly, when the basket is raised or lowered by the lifting device, in the event of the basket colliding with an obstacle, the operator is subjected to accelerations that may destabilize him. More generally, the operator is subjected to accelerations whenever the basket is moving relative to the ground, either horizontally or vertically.
[0009] DE-10 2019 213 972-A1 proposes, for example, to calculate the basket accelerations based on the basket height, the rolling speed of the articulated boom lift and based on a previously recorded profile of the road section where the articulated boom lift is traveling. In the event of excessive acceleration, the speed is reduced and / or an alert is given to the operator. This approach, however, remains limited to driving on roads whose profile has been previously analyzed and recorded.
[0010] It is these problems that the invention aims to address more specifically, by proposing an alert method in the event of an inappropriate situation, which is applicable regardless of the configuration of the road or the location where the lifting platform is located, and in an autonomous manner.
[0011] To this end, the invention relates to an alert method for alerting an operator in a basket of a lifting platform during a phase of movement of the basket relative to the ground, in which:
[0012] - the lifting platform includes:
[0013] • a chassis with wheels, the chassis being configured to move on the ground by rotating the wheels, the lifting platform being in a movement phase,
[0014] • a basket, configured to receive an on-board load comprising an operator and, possibly, one or more other persons, as well as objects such as tools and / or materials, the basket, the operator and any objects and persons on board the basket forming a loaded basket, and
[0015] • a lifting device, which connects the basket to the chassis and which is configured to move the basket relative to the ground between a low position, in which the lifting device is in a folded configuration, and a high position, in which the lifting device is in a deployed configuration, while the basket is in a moving phase, the alert method comprises an evaluation phase, during which an acceleration of the loaded basket is evaluated by means of an acceleration sensor, the alert method also comprises an alert phase, during which, if the acceleration evaluated during the evaluation phase is greater than a first predetermined acceleration threshold, then a first alert signal is emitted, by means of a first alert device of the lifting platform, for the attention of the operator present in the basket.
[0016] Thanks to the invention, the operator present in the basket receives an alert as soon as the acceleration of the loaded basket is greater than the first predetermined threshold, which generally indicates that the lifting platform is moving at an excessively high speed given the unevenness of the ground. The operator thus alerted then becomes aware of the potential danger and reduces, if necessary given the general condition of the ground, the rolling speed of the lifting platform, thereby reducing the risk of an accident. The alert method is notably based on measurements from sensors embedded in the lifting platform and on calculations made from these measurements, the alert method being able to be implemented autonomously, independently of the location where the lifting platform is moving, in particular without prior mapping.
[0017] According to advantageous but not mandatory aspects of the invention, such an alert method may incorporate one or more of the following features taken in isolation or in any technically admissible combination:
[0018] The acceleration sensor is an accelerometer, which is attached to the basket and is configured to measure accelerations experienced by the loaded basket.
[0019] The acceleration sensor is a load sensor, which is interposed between the lifting device and the basket, the load sensor being configured to measure a total mass of the loaded basket,
[0020] The alert method comprises an initial phase, which is prior to the evaluation phase and during which a static load of the loaded basket is measured using the load sensor while the basket is stationary, the static load being proportional to a force exerted by the loaded basket on the lifting device, while then, during the evaluation phase: • a dynamic load of the loaded basket is measured using the load sensor, which is proportional to a force exerted by the loaded basket on the lifting device, and
[0021] • then, using a lifting platform calculator, the acceleration of the loaded basket is calculated, the acceleration of the loaded basket being proportional to the dynamic load divided by the static load.
[0022] The static load, measured during the initial phase, is a vertical component of the force exerted by the loaded basket on the lifting device, and the dynamic load, measured during the evaluation phase, is a vertical component of the force exerted by the loaded basket on the lifting device.
[0023] - During the evaluation phase, the basket is moving relative to the ground without encountering any obstacle.
[0024] During the alert phase, if the acceleration of the loaded basket is greater than a second predetermined acceleration threshold, the second threshold being strictly greater than the first threshold, then a second alert signal is transmitted by means of a second alert device:
[0025] • for the attention of a remote operator, the second alert device including means of transmission, and / or
[0026] • for the attention of people around the lifting platform, the second warning device including sound and / or light warning means.
[0027] The basket movement phase is a ground movement phase of the lifting platform, while the chassis moves on the ground, and the height of the basket relative to the ground is fixed, while the first acceleration threshold depends on a movement speed of the lifting platform.
[0028] The lifting platform is configured to move on the ground at a travel speed chosen by the operator present in the basket, the travel speed being lower than a maximum travel speed, while an intermediate speed threshold is defined, which is non-zero and strictly lower than the maximum speed, that if the travel speed is lower than the intermediate speed threshold, then the first acceleration threshold is equal to a first value, while if the travel speed is between the intermediate speed threshold and the maximum speed, then the first acceleration threshold is equal to a second value, which is different from the first value, and that the first value is greater than the second value.
[0029] The first acceleration threshold depends on the height of the basket.
[0030] The basket moving phase is a basket lifting phase, as the lifting device raises or lowers the basket, while the first acceleration threshold depends on a basket height.
[0031] The invention also relates to a lifting platform, in particular an articulated platform, the lifting platform comprising:
[0032] - a chassis with wheels, the chassis being configured to move on the ground,
[0033] - a basket, configured to receive at least one operator and, possibly, objects such as tools and / or materials,
[0034] - a lifting device, which connects the basket to the chassis, the lifting device being configured to move the basket relative to the ground between a low position, in which the lifting device is in a folded configuration, and a high position, in which the lifting device is in a deployed configuration,
[0035] - a calculator, configured to record the values measured by the load sensor, and to perform calculations from the measured values, an alert device, configured to emit an alert signal to an operator present in the basket, while the lifting platform is configured to implement the alert method as described previously.
[0036] Advantageously:
[0037] - the lifting platform is an articulated platform, the lifting device being a lifting arm, which is connected to the basket by a joint, the acceleration sensor is a load sensor, which is interposed between the lifting arm and the basket, the load sensor being configured to measure the force exerted by the loaded basket on the lifting arm both when the basket is stationary relative to the ground and when the basket is moving relative to the ground.
[0038] 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 an alert method and of a lifting platform, in accordance with its principle, given solely by way of example and made with reference to the appended drawings, in which: - [Fig 1] Figure 1 is a side view of a lifting platform in accordance with the invention, shown in a lowered configuration;
[0039] - [Fig 2] Figure 2 is a view similar to Figure 1, the lifting platform being shown in a deployed configuration;
[0040] - [Fig 3] Figure 3 is a block diagram illustrating an alert method in accordance with the invention, and
[0041] - [Fig 4] Figure 4 represents, on two inserts a) and b), examples of charts used in alert methods in accordance with the invention.
[0042] A lifting platform 10 is shown in Figure 1. The lifting platform 10, also simply called "platform" in the context of the present description, comprises a chassis 12, which rests on a ground 14 by means of wheels 16. The chassis 12 is configured to move on the ground 14 by rotating the wheels 16, the lifting platform 10 then being in a movement phase. When the wheels 16 are not rotating, the chassis 12 is stationary relative to the ground 14, or simply said to be "stationary". The ground 14 is here assumed to be horizontal, the following description being given in relation to the orientation of the parts as shown in the figures, knowing that it may be otherwise in reality.
[0043] The nacelle 10 also comprises a basket 20. The basket 20 comprises a platform 21 A and a guardrail 21 B, which surmounts the platform 21 A. The basket 20 is configured to receive an on-board load, which includes in particular an operator 22. The basket 20 is equipped with a control console 24, by which the operator 22 controls the nacelle 10, in particular by which the operator controls the movement on the ground of the nacelle 10, a height of the basket 20, etc. The basket 20 is also configured to receive, if necessary, one or more other persons, as well as objects such as tools and / or materials. The basket 20, the operator 22 and any objects and persons embarked in the basket together form a basket 20 called “loaded”.
[0044] The lifting platform 10 also comprises a first warning device 25A. The first warning device 25A, represented here schematically by an indicator light arranged on the console 24, is configured to emit a first warning signal to the operator 22 present in the basket 20. In the example illustrated, the first warning signal is thus a light signal. Alternatively or additionally, the warning device 25 comprises audible warning means.
[0045] Advantageously, the lifting platform 10 also comprises a second alert device 25B. The second alert device 25B is here represented schematically by an antenna fixed to the chassis 12. In the example illustrated, the second alert device 25B comprises transmission means, in particular by radio frequency, and is configured to transmit a second alert signal to the attention of a so-called “remote” operator. The remote operator, who is not shown, is for example a manager of the lifting platform 10, or an operations supervisor, a safety manager, etc.
[0046] Alternatively or in addition, the second alert device 25B is also configured to emit an alert signal to the attention of the people located around the lifting platform 10, the second alert device 25B then including sound alert means - for example a horn - and / or light alert means - for example a flashing light -. By the expression "located around the lifting platform 10", we mean the people who are close to the lifting platform 10, for example on the ground 14, but who are not in the basket 20.
[0047] The nacelle 10 also comprises a lifting device 30. The lifting device 30 connects the basket 20 to the chassis 12 and is configured to lift the basket 20 relative to the chassis 12 between a low position, in which the lifting device 30 is in a folded configuration, and a high position, in which the lifting device 30 is in a deployed configuration. In FIG. 1, the nacelle 10 is shown in the folded configuration, while in FIG. 2, the nacelle 10 is shown in the deployed configuration. By extension, when the aerial work platform 10 is in the folded configuration, the lifting device 30 is also said to be in a folded configuration, while when the aerial work platform 10 is in the deployed configuration, the lifting device 30 is also said to be in a deployed configuration.The height of the basket 20 relative to the chassis 12, and by extension relative to the ground 14, is controlled by the operator 22 using the console 24.
[0048] Thus the lifting device 30 is configured to move the basket 20 relative to the ground 14, according to a movement substantially orthogonal to the ground 14, while the chassis 12 is configured to move the basket 20 relative to the ground 14, according to a movement substantially parallel to the ground 14.
[0049] In the illustrated example, the lifting device 30 is a lifting arm 32, which is connected to the nacelle 20 by an articulation 33. The articulation 33 is in particular configured to keep the platform 21A substantially parallel to the ground 14 when the basket 20 is raised or lowered by the lifting arm 32. The lifting nacelle 10 is thus an articulated nacelle. The principles of the invention, described with reference to the articulated nacelle shown in the drawings, are transposable to other types of lifting nacelle 10, in particular scissor, telescopic, mast, etc. The lifting device 30 also comprises an actuator 34, here a hydraulic cylinder, which is configured to control the deployment of the lifting device 32.
[0050] An operating phase of the lifting platform 10, called the “approach phase”, is defined during which the lifting platform 10 moves on the ground 14, while maintaining the lifting device 30 in the folded configuration. The approach phase is therefore a particular case of the movement phase of the lifting platform 10.
[0051] The lifting platform 10 also comprises an acceleration sensor 40, which is configured to measure an acceleration of the basket 20, in particular of the loaded basket 20. In particular, the acceleration sensor 40 is configured to carry out measurements of acceleration undergone by the loaded basket 20 when the lifting platform 10 is in the movement phase, in particular when the lifting platform 10 is in the approach phase. It is understood that the values measured by the acceleration sensor 40 vary continuously, in particular in connection with the movement speed of the lifting platform 10, with a profile of the ground on which the platform 10 is moving, with the height of the basket 20, etc. then measures a so-called “dynamic” load.
[0052] In the illustrated example, the acceleration sensor 40 is a load sensor 40A, which is interposed between the lifting device 30 and the basket 20, the load sensor 40A being configured to measure a total mass of the loaded basket 20, in particular when the basket 20 is stationary. The acceleration sensor 40 then measures a so-called “static” load, which is proportional to a force exerted by the loaded basket 20 on the lifting device 30.
[0053] In the illustrated example, the lifting platform 10 is an articulated platform, and the load sensor 40A is advantageously located at a junction of the lifting device 30 and the basket 20. In particular, the load sensor 40A is advantageously integrated into the articulation 33. According to a non-limiting example, the load sensor 40A includes one or more strain gauges, which are positioned on elements of the articulation 33 and which are configured to measure a force exerted by the loaded basket 20 on the lifting device 30, a total mass of the loaded basket 20 being deduced from this force measurement, according to known methods and not detailed further in the present description.
[0054] Other implementations of the load sensor are of course possible. According to a variant not shown, one or more load sensors are interposed between the lifting device 30 and the platform 21 A, in other words between the lifting device 30 and the basket 20, so as to measure a total load of the basket 20. For example, four load sensors are located at the four corners of the platform 21 A and support the platform 21 A, the platform 21 A being generally rectangular. The lifting platform 10 advantageously comprises a computer, which is configured to calculate, from the static load and dynamic load measurements of the loaded basket 20, an acceleration value undergone by the basket 20 when the basket 20 is in the movement phase, here in the movement phase parallel to the ground 14. The acceleration of the loaded basket 20 is thus proportional to the dynamic load divided by the static load.The computer, which is not shown, is for example integrated into the console 24. When the lifting platform 10 moves on the ground 14, in particular when the ground 14 is uneven, the operator present in the basket 20 undergoes accelerations, which are all the more significant as the unevenness of the ground is significant and / or the speed of movement on the ground is significant. The greater these vertical accelerations, the greater the risk that the operator will lose his balance. It is thus understood the relevance of alerting the operator before an accident occurs.
[0055] The lifting platform 10 is configured to implement an alert method in accordance with the invention, an example of the alert method being detailed below, with reference to FIG. 3.
[0056] The alert method comprises an initial phase 100, during which a static load of the loaded basket 20 is measured by means of the load sensor 40A and while the lifting platform 10 is stationary, the static load being proportional to a force exerted by the loaded basket 20 on the lifting device 30.
[0057] The alert method also comprises an evaluation phase 101, which is subsequent to the initial phase 100 and during which an acceleration A101 of the loaded basket 20 is evaluated by means of the acceleration sensor 40, in particular by means of the load sensor 40A, while the basket 20 is moving relative to the ground 14. In a first example, the lifting platform 10 is in the movement phase, and the basket 2 is moving parallel to the ground 14.
[0058] In the illustrated example, the acceleration A101 of the loaded basket 20 is evaluated by measuring the dynamic load of the basket, then by calculating the acceleration of the loaded basket 20, using the computer of the articulated platform, the acceleration of the loaded basket 20 being proportional to the dynamic load divided by the static load. Advantageously, during the evaluation phase 101, the acceleration measurement signal A101 is filtered, for example by exponential filtering. The objective of the filtering is to avoid false positives. For example, when driving at high speed on a grooved surface, for example on a paved road, dynamic load variations of low amplitude and high frequency can be read, without any consequence on the balance of the driver. The filtering is for example carried out via a low-pass filter, allowing only low frequencies to pass.The alert method also comprises an alert phase 102, during which, if the acceleration evaluated during the evaluation phase 101 is greater than a first predetermined acceleration threshold A1, then a first alert signal is emitted, by means of the first alert device 25A, to the attention of the operator 22 present in the basket 20. The first acceleration threshold A1 is chosen to correspond to situations where the rolling is done at too high a speed in view of the unevenness of the ground 14 on which the lifting platform 10 is moving. Thus the first acceleration threshold A1 is established to signal accelerations which begin to present a risk for the stability of the operator. The operator is thus alerted to a potentially dangerous situation. The first acceleration threshold A1 is expressed in acceleration units “g”, and is of the order of 1.2 g to 1.4 g.More generally, the method of the invention is implemented while the basket 20 is in a movement phase without encountering an obstacle.
[0059] Thus, when the operator receives the first alert signal emitted by the first alert device 25A, the operator becomes aware of the potential danger to which he is subjected and, if necessary, reduces the speed of movement of the lifting platform 20.
[0060] According to another advantageous aspect, if, during the alert phase 102, the acceleration A101 of the loaded basket 20 is greater than a second predetermined acceleration threshold A2, the second acceleration threshold A2 being strictly greater than the first acceleration threshold A1, then during the alert phase 102 a second alert signal is transmitted by means of the second alert device 25B. For example, the second alert signal is transmitted for the attention of a remote operator. Alternatively or in addition, the second alert signal is transmitted for the attention of people around the lifting platform 10.
[0061] The second acceleration threshold A2 is for example chosen so that its exceedance indicates an abnormal situation, potentially dangerous for the operator and / or causing damage to the lifting platform 10. The remote operator or the people around the lifting platform 20, thus alerted, can then take the necessary measures, these measures including alerting emergency services, and / or scheduling a maintenance visit to the lifting platform 10, etc. In practice, the thresholds A1 and A2 are established for each model of platform by an experiment plan in real conditions. Typically, the second acceleration threshold A2 is of the order of 1.5 to 2 times the first acceleration threshold A1.
[0062] According to another aspect of the invention illustrated in Figure 4, the first acceleration threshold A1 advantageously depends on a ground travel speed V of the articulated nacelle 20. The objective being to encourage the operator to adopt more cautious driving, the first acceleration threshold A1 preferably decreases as the ground travel speed V increases. Similarly, the second acceleration threshold A2 also decreases as the ground travel speed V increases.
[0063] Figure 4a) is an abacus 41 comprising a curve C401 illustrating the evolution of the first acceleration threshold A1, expressed in m / s 2 - meter per second squared - depending on the speed V of movement on the ground of the lifting platform 10, the speed V being expressed in m / s - meter per second - or in km / h.
[0064] Generally, the lifting platform 10 is configured to move on the ground at a movement speed chosen by the operator 22 present in the basket 20, the movement speed being less than a maximum movement speed Vmax. The speed Vmax advantageously depends on the configuration of the lifting device 30. According to a first non-limiting example, when the lifting platform 10 is in the approach phase, in other words when the lifting device 30 is in the folded configuration, the maximum speed Vmax is equal to 5 km / h. According to a second non-limiting example, when the lifting device 30 is in the deployed configuration, the maximum speed Vmax is strictly less than 5 km / h, for example equal to 2 km / h.
[0065] We define an intermediate speed threshold Vi, the intermediate speed threshold Vi being non-zero and strictly lower than the maximum speed Vmax. For example, the intermediate speed threshold Vi is equal to 40% of the maximum speed Vmax.
[0066] If the ground movement speed V of the nacelle 10 is lower than the intermediate speed threshold Vi, then the first acceleration threshold A1 is equal to a first predetermined value A401, while if the movement speed V is between the intermediate speed threshold Vi and the maximum speed Vmax, then the first acceleration threshold A1 is equal to a second value A402. Advantageously, the first value A401 is greater than the second value A402.
[0067] The alert method according to the invention is thus implemented with acceleration thresholds which depend on the speed, so as to improve the relevance of the first alert signal in the event of the acceleration threshold being exceeded, while reducing the number of false positives, which would risk “wearing off” the operator 22, who would no longer pay attention to the first alert signal.
[0068] In the alternative example illustrated in Figure 4b), the first acceleration threshold A1 and the second acceleration threshold A2 both vary as a function of the speed of movement V of the lifting platform 20. Figure 4b) is a chart 42 comprising a first curve C421 illustrating the evolution of the first acceleration threshold A1 as a function of the speed V of movement on the ground of the lifting platform 20. The chart 42 also comprising a second curve C422 illustrating the evolution of the second acceleration threshold A2 as a function of the speed V of movement on the ground of the lifting platform 20. A first speed threshold V1 is defined, which is non-zero and strictly lower than the maximum speed Vmax. A second speed threshold V2 is defined, which is intermediate between the first speed threshold V1 and the maximum speed Vmax.For example, the maximum speed Vmax is equal to 5 km / h, the first speed threshold V1 is equal to 1 km / h, and the second speed threshold V2 is equal to 2.5 km / h.
[0069] In the example illustrated, when the speed V is lower than the first speed threshold V1, the first acceleration threshold A1 is equal to a first value AT. When the speed V is between the first speed threshold V1 and the second threshold V2, the first acceleration threshold A1 is equal to a second value A1”, which is strictly lower than the first value AT of the first acceleration threshold A1. When the speed V is between the second speed threshold V2 and the maximum speed Vmax, the first acceleration threshold A1 is equal to a third value AT”, which is strictly lower than the second value A1” of the first acceleration threshold A1.
[0070] Similarly, when the speed V is lower than the first speed threshold V1, the second acceleration threshold A2 is equal to a first value A2'. When the speed V is between the first speed threshold V1 and the second threshold V2, the second acceleration threshold A2 is equal to a second value A2”, which is strictly lower than the first value A2' of the second acceleration threshold A2. When the speed V is between the second speed threshold V2 and the maximum speed Vmax, the second acceleration threshold A2 is equal to a third value A2'”, which is strictly lower than the second value A2” of the second acceleration threshold A2.
[0071] More generally, it is understood that multiple approaches are possible to define, as a function of the speed of movement V of the lifting platform 20, one or more predetermined acceleration thresholds, so as to distinguish between “normal” operating situations of the lifting platform 20, where the operator 22 is not in danger and where no alert is necessary, inappropriate situations, where it is appropriate to alert the operator 22 so that he reduces, if necessary, the speed of movement of the lifting platform 10, and dangerous situations, where it is appropriate to alert a remote operator, or the people located around the lifting platform, so as to rescue the operator 22 on board the basket 20, or to organize an inspection of the lifting platform 10.
[0072] In the example illustrated, the acceleration sensor 40 is a load sensor 40A integrated into the joint 33. In a variant not shown, the acceleration sensor 40 is arranged differently, for example integrated into the actuator 34.
[0073] In the illustrated example, the acceleration sensor 40 measures, during the initial phase 100, a vertical component of the force exerted by the loaded basket on the lifting device 30. When the ground 12 is horizontal, the acceleration sensor 40 thus measures the weight of the loaded basket 20. Similarly, the dynamic load, measured during the evaluation phase 101, is a vertical component of the force exerted by the loaded basket 20 on the lifting device 30.
[0074] According to a variant not shown, the acceleration sensor 40 is an accelerometer, which directly measures the accelerations undergone by the basket 20, without needing to calculate a ratio between the dynamic and static load measurements. In other words, the initial phase 100 can be omitted. For example, the acceleration sensor 40 is an accelerometer attached to the platform 21 A.
[0075] In the illustrated example, the first acceleration threshold A1 and the second acceleration threshold A2 are evaluated as a function of the vertical components of the loads, static or dynamic, measured by the acceleration sensor. In a variant not shown, other components - other than the vertical component - of the acceleration of the basket 20 are taken into account, for example a longitudinal component of the acceleration of the basket 20, and / or a transverse component of the acceleration of the basket 20. The longitudinal component is substantially parallel to a direction of movement of the lifting cradle 10 on the ground 12, while the transverse component is parallel to the ground 12 and orthogonal to the direction of movement of the cradle 10 on the ground 12.
[0076] The embodiments and variations mentioned above can be combined with each other to generate new embodiments of the invention.
Claims
CLAIMS 1. Alert method for alerting an operator (22) in a basket (20) of a lifting platform (10) during a phase of movement of the basket (20) relative to the ground (14), in which: the lifting platform (10) comprises: • a chassis (12) with wheels (16), the chassis (12) being configured to move on the ground (14) by rotating the wheels (16), the lifting platform (10) being in a movement phase, • a basket (20), configured to receive an on-board load comprising an operator (22) and, optionally, one or more other persons, as well as objects such as tools and / or materials, the basket (20), the operator (22) and any objects and persons on board the basket (20) forming a loaded basket (20), and • a lifting device (30), which connects the basket (20) to the chassis (12) and which is configured to move the basket (20) relative to the ground (14) between a low position, in which the lifting device (30) is in a folded configuration, and a high position, in which the lifting device (30) is in a deployed configuration, while the basket (20) is in a moving phase, the alert method comprises an evaluation phase (101), during which an acceleration of the loaded basket (20) is evaluated by means of an acceleration sensor (40, 40A), the alert method also comprises an alert phase (102), during which, if the acceleration evaluated during the evaluation phase (101) is greater than a first predetermined acceleration threshold (A1), then a first alert signal is emitted, by means of a first alert device (25A) of the nacelle lifting device (10), for the attention of the operator (22) present in the basket (20),the first acceleration threshold (A1) being between 1.2g and 1.4g, the phase of movement of the basket (20) is a phase of movement on the ground of the lifting platform (10), while the chassis (12) moves on the ground (14)., 2. The alert method of claim 1, wherein: the acceleration sensor (40) is an accelerometer, which is attached to the basket (20) and which is configured to measure accelerations experienced by the loaded basket (20).
3. Alert method according to claim 1, wherein: the acceleration sensor (40) is a load sensor (40A), which is interposed between the lifting device (30) and the basket (20), the load sensor (40A) being configured to measure a total mass of the loaded basket (20), the alert method comprises an initial phase (100), which is prior to the evaluation phase (101) and during which a static load of the loaded basket (20) is measured by means of the load sensor (40A) and while the basket (20) is stationary, the static load being proportional to a force exerted by the loaded basket (20) on the lifting device (30), then, during the evaluation phase (101): • a dynamic load of the loaded basket (20) is measured by means of the load sensor (40A), which is proportional to a force exerted by the loaded basket (20) on the lifting device (30), and • then, using a lifting platform calculator (10), the acceleration of the loaded basket (20) is calculated, the acceleration of the loaded basket (20) being proportional to the dynamic load divided by the static load.
4. Alert method according to claim 3, wherein: the static load, measured during the initial phase (100), is a vertical component of the force exerted by the loaded basket (20) on the lifting device (30), and the dynamic load, measured during the evaluation phase (101), is a vertical component of the force exerted by the loaded basket (20) on the lifting device (30).
5. Alert method according to any one of claims 1 to 4, wherein: during the evaluation phase (101), the basket (20) is moving relative to the ground (14) without encountering an obstacle.
6. Alert method according to any one of claims 1 to 5, wherein: during the alert phase (102), if the acceleration of the loaded basket (20) is greater than a second predetermined acceleration threshold (A2), the second threshold (A2) being strictly greater than the first threshold (A1), then a second alert signal is transmitted by means of a second alert device (25B): • for the attention of a remote operator, the second alert device (25B) including transmission means, and / or • for the attention of people around the lifting platform (10), the second alert device (25B) including sound and / or light alert means.
7. Alert method according to any one of claims 1 to 6, in which: the first acceleration threshold (A1) depends on a movement speed (V) of the lifting platform (10).
8. Alert method according to claim 7, wherein: the lifting platform (10) is configured to move on the ground (14) at a movement speed (V) chosen by the operator (22) present in the basket (20), the movement speed being less than a maximum movement speed (Vmax), an intermediate speed threshold (Vi) is defined, which is non-zero and strictly less than the maximum speed (Vmax), if the movement speed (V) is less than the intermediate speed threshold (Vi), then the first acceleration threshold (A1) is equal to a first value (A401), while if the movement speed (V) is between the intermediate speed threshold (Vi) and the maximum speed (Vmax), then the first acceleration threshold (A1) is equal to a second value (A402), which is different from the first value (A401), the first value (A401) is greater than the second value (A402).
9. An alert method according to any one of claims 1 to 8, wherein: a height of the basket (20) relative to the ground (14) is fixed while the chassis (12) moves on the ground, and the first acceleration threshold (A1) depends on the height of the basket (20).
10. Lifting platform (10), in particular an articulated platform, the lifting platform (10) comprising: a chassis (12) with wheels (16), the chassis (12) being configured to move on the ground (14), a basket (20), configured to receive at least one operator (22) and, optionally, objects such as tools and / or materials, a lifting device (30), which connects the basket (20) to the chassis (12), the lifting device (30) being configured to move the basket (20) relative to the ground (14) between a low position, in which the lifting device (30) is in a folded configuration, and a high position, in which the lifting device (30) is in a deployed configuration, a calculator, configured to record the values measured by the load sensor (40, 40A), and to perform calculations from the measured values, an alert device (25A), configured to emit an alert signal to the attention of an operator (22) present in the basket (20), wherein the lifting platform (10) is configured to implement the alert method according to any one of claims 1 to 9.
11. Lifting platform (10) according to claim 10, wherein: the lifting platform (10) is an articulated platform, the lifting device (30) being a lifting arm (32), which is connected to the basket (20) by an articulation (33), the acceleration sensor (40) is a load sensor (40A), which is interposed between the lifting arm (30) and the basket (20), the load sensor (40A) being configured to measure the force exerted by the loaded basket (20) on the lifting arm (30) both when the basket (20) is stationary relative to the ground (14) and when the basket (20) is moving relative to the ground (14).