Tower crane and control method, device and processor therefor

Abstract

Embodiments of the present application provide a control method, a control device, a processor, a tower crane and a machine readable storage medium for a tower crane. The tower crane comprises a hinged tower body and a superstructure. The superstructure comprises a balance arm, a hoisting arm, a fixed counterweight and a movable counterweight. The superstructure is provided with a guide rail extending from the balance arm side to the hoisting arm side. The movable counterweight is movable along the guide rail. The control method comprises: determining a hoisting load bending moment of the tower crane; determining a first target position of the movable counterweight according to at least the hoisting load bending moment; and controlling the movable counterweight to move to the first target position; wherein, when the movable counterweight is located at the first target position, in the case of sudden unloading of the tower crane, after at least a part of the fixed counterweight falls off, a first bending moment of the superstructure has a downward turning tendency relative to the hinged point of the superstructure and the tower body. Through the above scheme, the sudden unloading overturning resistance of the tower crane can be improved.

Description

Technical Field

[0001] This application relates to the field of computer technology, and more specifically to a control method, control device, processor, tower crane, and machine-readable storage medium for a tower crane. Background Technology

[0002] Tower cranes (also known as tower hoists or tower cranes) are key pieces of equipment in modern construction and are widely used in building, wind power, and nuclear power construction. Due to the specific characteristics of some industries, the prevention of secondary damage caused by tower crane overturning is of paramount importance, and the requirements for tower crane overturning resistance are becoming increasingly stringent.

[0003] Currently, tower crane anti-tipping measures primarily rely on adjusting the overall weight distribution and strengthening the tower body based on traditional tower crane structures to improve their anti-tipping performance. However, with the increasing load weight of tower cranes, this anti-tipping design becomes less effective, especially during sudden unloading of ultra-large tower cranes, where simply adjusting structural mass and strength is insufficient to achieve anti-tipping capabilities. Therefore, improving the anti-tipping capability of tower cranes during sudden unloading remains a key technical challenge for the industry, particularly in the era of large and even ultra-large tower cranes. Summary of the Invention

[0004] The purpose of this application is to provide a control method, control device, processor, tower crane, and machine-readable storage medium for tower cranes, which can improve the anti-overturning ability of tower cranes when suddenly unloaded.

[0005] To achieve the above objectives, a first aspect of this application provides a control method for a tower crane. The tower crane includes a hinged tower body and a superstructure. The superstructure includes a counterweight boom, a jib boom, a fixed counterweight, and a movable counterweight. The fixed counterweight is fixed to the counterweight boom side. The superstructure is provided with a guide rail extending from the counterweight boom side to the jib boom side. The movable counterweight is movable along the guide rail. The control method includes:

[0006] Determine the lifting bending moment of the tower crane;

[0007] Determine the first target position of the moving counterweight based on at least the lifting bending moment; and

[0008] Control the moving counterweight to move to the first target position;

[0009] When the moving counterweight is at the first target position, in the event of a sudden unloading of the tower crane, after at least a portion of the fixed counterweight falls off, the first bending moment of the superstructure relative to the hinge point between the superstructure and the tower body causes the boom to tend to rotate downwards.

[0010] In this embodiment of the application, determining the lifting bending moment of the tower crane includes:

[0011] Obtain the weight and lifting position of the object being lifted;

[0012] The lifting moment of the tower crane is determined based on the weight of the object being lifted and the lifting position.

[0013] In this embodiment, the hinge point is located on the side of the balance arm.

[0014] In this embodiment of the application, when the moving counterweight is located at the first target position, when the tower crane is lifting the load, the first bending moment relative to the hinge point causes the boom to tend to rotate downward.

[0015] In this embodiment of the application, the control method further includes:

[0016] Compare the lifting bending moment with the set bending moment;

[0017] Determining the first target position of the moving counterweight based on the minimum lifting moment includes: when the lifting moment is greater than a set moment, determining the first target position of the moving counterweight based on the minimum lifting moment.

[0018] In this embodiment of the application, the control method further includes:

[0019] If the lifting bending moment is less than the set bending moment, then the second target position is determined based on the lifting bending moment; and

[0020] Control the moving counterweight to move to the second target position;

[0021] Specifically, when the moving counterweight is at the second target position, and the tower crane is lifting the load, the second bending moment of the upper structure is located on the side of the crane boom.

[0022] In this embodiment of the application, a luffing trolley that moves along the boom is provided on the boom, and the control method further includes:

[0023] If the second bending moment exceeds the preset bending moment threshold, the luffing trolley is prohibited from luffing to the far end of the boom.

[0024] In this embodiment of the application, determining the first target position of the moving counterweight based on the lifting bending moment includes:

[0025] The minimum load bending moment is input into the predetermined location determination model to obtain the first target location.

[0026] In this embodiment of the application, the location determination model is obtained through the following steps:

[0027] Obtain simulation data for the tower crane, including at least two of the following: load weight, load boom, load moment, and the optimal position of the moving counterweight corresponding to the load moment.

[0028] Using at least two of the lifting weight, lifting boom, and lifting bending moment as independent variables, and the optimal position of the moving counterweight as the dependent variable, data fitting is performed.

[0029] If the fitted data is distributed linearly or regularly, then the fitted function is obtained to obtain the location determination model;

[0030] If the fitted data is distributed in a non-linear mapping relationship, then a neural network is used to fit the simulation data to obtain a location determination model;

[0031] At least two of the load weight, load boom, and load bending moment input into the position determination model, along with the position of the moving counterweight output by the position determination model, are input into the simulation model of the tower crane controller to verify the position determination model.

[0032] If the location determination model fails the verification, a mapping table is generated based on the simulation data, which maps at least two of the load weight, load arm, and load bending moment to the position of the moving counterweight. The location determination model is then obtained based on the mapping table and the interpolation function.

[0033] A second aspect of this application provides a processor configured to execute the above-described control method for a tower crane.

[0034] A third aspect of this application provides a control device for a tower crane. The tower crane includes a hinged tower body and a superstructure. The superstructure includes a counterweight boom, a jib boom, a fixed counterweight, and a movable counterweight. The fixed counterweight is fixed to the counterweight boom side. The superstructure is provided with a guide rail extending from the counterweight boom side to the jib boom side. The movable counterweight is movable along the guide rail. The control device includes:

[0035] Drive mechanism, used to drive the movable counterweight to move along the guide rail, and

[0036] The processor mentioned above.

[0037] In this embodiment of the application, the control device further includes:

[0038] Position detection equipment is used to detect the position of a moving counterweight.

[0039] A fourth aspect of this application provides a tower crane, comprising:

[0040] Tower body;

[0041] The upper structure, hinged to the tower body, includes:

[0042] The counterweight arm is equipped with a fixed counterweight.

[0043] Crane boom; and

[0044] The mobile counterweight is equipped with a guide rail extending from the counterweight arm to the crane arm, allowing the mobile counterweight to move along the guide rail.

[0045] The aforementioned control device for tower cranes.

[0046] In this application embodiment, the tower crane includes a crawler tower crane.

[0047] The fifth aspect of this application provides a machine-readable storage medium storing instructions that, when executed by a processor, cause the processor to implement the aforementioned control method for a tower crane.

[0048] The above scheme determines the target position of the moving counterweight based on the minimum lifting moment. The moving counterweight is then moved to the target position. When the tower crane suddenly unloads, the bending moment after the fixed counterweight falls off causes the boom to tend to rotate downwards, thereby suppressing the boom from rising and absorbing kinetic energy.

[0049] Other features and advantages of the embodiments of this application will be described in detail in the following detailed description section. Attached Figure Description

[0050] The accompanying drawings are provided to further illustrate the embodiments of this application and form part of the specification. They are used together with the following detailed description to explain the embodiments of this application, but do not constitute a limitation on the embodiments of this application. In the drawings:

[0051] Figure 1 A schematic diagram of the structure of a tower crane according to an embodiment of this application is shown.

[0052] Figure 2 A schematic flowchart of a control method for a tower crane according to an embodiment of this application is shown.

[0053] Figure 3 A schematic block diagram of a control device for a tower crane according to an embodiment of this application is shown.

[0054] Figures 4A-4E A schematic block diagram of a drive mechanism according to an embodiment of this application is shown; and

[0055] Figure 5 The illustration shows the tower crane's superstructure in an upward state when it is suddenly unloaded according to an embodiment of this application. Detailed Implementation

[0056] The specific embodiments of this application will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are for illustration and explanation only and are not intended to limit the embodiments of this application.

[0057] It should be noted that if the embodiments of this application involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0058] Furthermore, if the embodiments of this application involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, features defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed in this application.

[0059] In some large or even super-large tower crane applications (e.g., in bridges, nuclear power facilities, etc.), especially in mobile (e.g., crawler-mounted) tower crane applications, the weight of the counterweights used to match the load on the lifting and counterbalance jib sides can be very large. During the lifting process of such tower cranes, the torque on the counterbalance jib side changes significantly, resulting in a large torque acting on the tower body. To ensure safety, ideally, the tower's bending moment resistance should be increased, for example, by increasing the tower's volume. However, in actual tower structure design, it is impossible to increase the tower's volume and weight indefinitely. This means that higher requirements are placed on the torque balance on both sides of the counterbalance jib and the lifting jib.

[0060] Figure 1 A schematic diagram of a tower crane according to an embodiment of this application is shown. Figure 1As shown in this embodiment, the tower crane may include a tower body 110 and a superstructure, which can rotate around the tower body 110 (e.g., the slewing mechanism of the tower body). The superstructure may include a counterweight 120, a lifting jib 130, a fixed counterweight 140, and a movable counterweight 150. The fixed counterweight 140 may be fixed to the counterweight jib side, for example, at the far end of the counterweight jib 120 (i.e., away from the slewing center of the tower crane). The superstructure may be provided with a guide rail (not shown in the figure) extending from the counterweight jib side to the lifting jib side, and the movable counterweight 150 can move along the guide rail. The lifting jib 130 may be provided with a luffing trolley 160 and a slide rail for the luffing trolley 160 to move (luff), and the luffing trolley 160 can be connected to a hook 170 via a lifting rope.

[0061] Figure 2 A schematic flowchart of a control method for a tower crane according to an embodiment of this application is shown. Figure 2 The control method shown can be applied to Figure 1 In the tower crane shown. For example... Figure 2 As shown in the embodiments of this application, the control method may include the following steps.

[0062] In step S210, the lifting bending moment of the tower crane is determined.

[0063] Specifically, in one example, the weight of the load applied to the jib can be detected using a weight detection device. For example, an example of a weight detection device could include a load cell, which can be positioned at the hook to detect the weight of the load. The luffing radius of the luffing trolley (i.e., the distance of the luffing trolley along the jib from the tower crane's slewing center) can be detected, for example, using a position sensor (e.g., a rotary encoder or a drawbar sensor) to determine the lever arm of the load relative to the tower crane's slewing center (the location of the tower crane's slewing center is known). Based on the weight of the load and the lever arm, the moment of the load can be determined. Here, the load of the tower crane can include the sum of the weight of the load and the weight of the hook and the lifting rope, and the weights of the hook and the lifting rope can be predetermined. Therefore, obtaining the weight of the load yields the load (or load weight, lifting load), and based on the load and the lever arm, the lifting moment can be obtained. In another example, the weight of the load to be lifted can be obtained using machine vision. For example, a marker with the weight information of the object to be lifted can be affixed to it. An image of the marker can be acquired, and the weight information of the object can be obtained through semantic recognition. In another example, a pre-planned lifting task can be obtained, which may include information such as the weight of the object to be lifted and the lifting path. In yet another example, the lifting position can be obtained by detecting the luffing amplitude of the luffing trolley (i.e., the distance of the luffing trolley along the boom from the center of rotation of the tower crane). In yet another example, the lifting position can be obtained based on positioning technology (e.g., RTK). After obtaining the weight of the object and the lifting position, the distance between the line of action of the force exerted by the object on the boom and the center of rotation of the tower crane (i.e., the lever arm) can be determined based on the lifting position. In yet another example, the lifting bending moment can be directly measured by a torque sensor.

[0064] In step S220, the first target position of the moving counterweight is determined based on at least the lifting bending moment.

[0065] In step S230, the counterweight is controlled to move to the first target position;

[0066] When the moving counterweight is at the first target position, in the event of a sudden unloading of the tower crane, after at least a portion of the fixed counterweight falls off, the first bending moment of the superstructure relative to the hinge point between the superstructure and the tower body causes the boom to tend to rotate downwards.

[0067] Specifically, in the embodiments of this application, step S220 may include:

[0068] The minimum load bending moment is input into the predetermined location determination model to obtain the first target location.

[0069] In this embodiment of the application, the hinge point may be located on the side of the balance arm.

[0070] More specifically, in the embodiments of this application, the location determination model can be obtained through the following steps:

[0071] Obtain simulation data for the tower crane, including at least two of the following: load weight, load boom, load moment, and the optimal position of the moving counterweight corresponding to the load moment.

[0072] Using at least two of the lifting weight, lifting boom, and lifting bending moment as independent variables, and the optimal position of the moving counterweight as the dependent variable, data fitting is performed.

[0073] If the fitted data is distributed linearly or regularly, then the fitted function is obtained to obtain the location determination model;

[0074] If the fitted data is distributed in a non-linear mapping relationship, then an intelligent algorithm is used to fit the simulation data to obtain a location determination model;

[0075] At least two of the load weight, load boom, and load bending moment input into the position determination model, along with the position of the moving counterweight output by the position determination model, are input into the simulation model of the tower crane controller to verify the position determination model.

[0076] If the location determination model fails the verification, a mapping table is generated based on the simulation data, which maps at least two of the load weight, load arm, and load bending moment to the position of the moving counterweight. The location determination model is then obtained based on the mapping table and the interpolation function.

[0077] Specifically, in one example, simulation software (such as commercial simulation software) can be used to model the tower crane under study (of interest), i.e., to establish a simulation model of the tower crane. Specifically, a rigid body model can be established first: the tower crane can be divided into two moving bodies, the superstructure and the tower body, connected by a hinge kinematic pair at the rear hinge point (i.e., the counterweight boom side). Then, a flexible body computational model of the superstructure and tower body can be established to calculate their modal information. The rigid body model is then associated with the modal result file to achieve rigid-flexible coupling of the moving body model. Next, kinematic pairs, contacts, limiters, and other components are added and associated with the rigid-flexible coupling model to form a co-simulation model. Finally, various lifting conditions of the tower crane are determined, and the counterweight scheme parameters for different lifting conditions are input into the model. A sudden unloading process is then loaded to simulate the outrigger force, pitch angle, and other data information of the tower crane under different sudden unloading conditions.

[0078] Through multibody dynamics simulation or experiments, the optimal counterweight detachment time (detachment angle) and detachment weight, the optimal moving position of the moving counterweight and the corresponding bending moment were obtained.

[0079] After establishing the tower crane simulation model, it is necessary to obtain at least a set of data on the lifting bending moment and the corresponding optimal moving counterweight position through the simulation model. This optimal moving counterweight position should satisfy the following conditions:

[0080] When the moving counterweight is at the optimal moving counterweight position (i.e., the first target position), in the event of a sudden unloading of the tower crane, after at least a portion of the fixed counterweight detaches, the overall bending moment of the superstructure (i.e., the first bending moment) tends towards the jib side relative to the hinge point between the superstructure and the tower body. In other words, this bending moment causes the jib to tend to rotate downwards relative to the hinge point. The magnitude of the first bending moment can be determined according to the design requirements of the tower crane.

[0081] In a further example, it is expected that when the moving counterweight is at the first target position, when the tower crane is lifting the load, the first bending moment is inclined towards the boom side relative to the hinge point, that is, the bending moment causes the boom to tend to rotate downward relative to the hinge point.

[0082] This design can be applied to tower cranes where the superstructure is hinged to the tower body on the counterweight boom side (rear hinge point), while the jib side is either open to the tower body or has a detachable hinge relationship (e.g., a pluggable pin) (allowing the jib of the superstructure to tilt upwards around the rear hinge point). In the event of a sudden unloading of the tower crane and the fixed counterweight on the counterweight boom side detaching (the fixed counterweight detachment mechanism will be described in detail below), the overall bending moment of the superstructure tends towards the jib side, applying a downward force to the jib and inhibiting its tilting upwards. Furthermore, during normal lifting operations, it is also desirable for the overall torque of the superstructure to tend towards the jib side to inhibit its tilting upwards.

[0083] In a further example, since the lifting moment is determined by both the lifting weight and the lifting boom, relying solely on the lifting moment as a single parameter to determine the optimal position of the moving counterweight may not accurately reflect different lifting conditions. Therefore, a simulation model can be used to determine the mapping relationship between multiple parameters and the optimal position of the moving counterweight. In one example, a simulation model can be used to determine data sets relating at least two of the lifting weight, lifting boom, and lifting moment to the optimal position of the moving counterweight under different lifting conditions. After obtaining these data sets, a position determination model can be established.

[0084] Specifically, at least two of the following data sets—lifting weight, lifting boom, and lifting bending moment (e.g., lifting weight and lifting bending moment)—are used as independent variables, and the corresponding optimal moving counterweight position is used as the dependent variable for data fitting. Specifically, if the data distribution is linear or regular, a specific form of fitting function can be obtained through fitting to obtain a moving counterweight position calculation model, which is the position determination model. If the data has a non-linear mapping relationship, intelligent algorithms (e.g., BP neural networks, radial basis function algorithms, etc.) can be used to fit the data to obtain a moving counterweight position calculation model, which is the position determination model.

[0085] After obtaining the calculation model for the moving counterweight position in either of the two scenarios described above, the output of this calculation model (i.e., the optimal moving counterweight position (target position)) and the inputs (i.e., at least two of the lifting weight, lifting boom, and lifting bending moment) are substituted back into the simulation model to verify the output of the calculation model. If the verification passes (e.g., the output of the calculation model matches the result obtained through the simulation model, such as the difference between the two being within an acceptable error range), the calculation model is determined to be usable. If the verification fails, the data set is re-acquired through the simulation model, and the data fitting is performed again.

[0086] Due to poor data quality, low robustness of the computational model, and insufficient sample size, if the re-obtained computational model still fails the verification, then after reaching a certain condition (e.g., the number of refits exceeds N, where N can be a set number of refits), data fitting is no longer performed. Instead, a mapping table is formed based on the data obtained from the simulation model, mapping at least two of the load weight, load arm, and load bending moment to the optimal moving counterweight position, and then an interpolation function is determined. The target position of the moving counterweight can be determined based on the mapping table and the interpolation function. In this case, the position determination model can include a combination of the mapping table and the interpolation function. The closest data can be found from the mapping table based on at least two of the determined load bending moment, load weight, and load arm, and then the target position of the moving counterweight is obtained using the interpolation function.

[0087] In the embodiments of this application, the lifting conditions can be divided into two main categories. One category is when the lifting bending moment is less than a set value M1 (which can be considered a small lifting condition), the tower crane's strength is sufficient to withstand (hard-handle) the sudden unloading condition. Simply moving the counterweight can change the overall bending moment state of the superstructure, thereby improving the tower crane's ability to withstand sudden unloading. The other category is when the lifting bending moment is greater than the set value M1 (which can be considered a large lifting condition), the tower body's strength is insufficient to withstand the sudden unloading condition. In this case, the coordinated action of moving and dropping counterweights is required to prevent the tower crane from overturning.

[0088] When the lifting moment is less than M1, the bending moment of the superstructure is tilted forward as much as possible when the moving counterweight is adjusted to normal lifting conditions (assuming that the limit of the bending moment of the tower body tilting forward (i.e. the side of the crane boom) is M2, where M2 > M1), so that when the tower crane is suddenly unloaded, the forward tilting moment can cancel the impact moment of the sudden unloading, thus improving the effect of the sudden unloading condition.

[0089] When the lifting bending moment is greater than M1, the target position (first target position) of the moving counterweight can be determined as described in the above embodiment.

[0090] Therefore, in the embodiments of this application, the control method may further include:

[0091] Compare the lifting bending moment with the set bending moment;

[0092] If the lifting bending moment is less than the set bending moment, then the second target position is determined based on the lifting bending moment; and

[0093] Control the moving counterweight to move to the second target position;

[0094] Specifically, when the moving counterweight is at the second target position, and the tower crane is lifting the load, the second bending moment of the upper structure is located on the side of the crane boom.

[0095] In this embodiment, the second bending moment can be determined (designed) based on the maximum bending moment that the tower crane can withstand. For example, the second bending moment may not exceed the maximum bending moment. In one example, the range of the second bending moment can be 50% to 95% of the maximum bending moment.

[0096] In this embodiment of the application, when the second bending moment is close to the maximum bending moment, for safety reasons, the outward luffing of the luffing trolley can be restricted to increase the second bending moment. Specifically, the control method may further include:

[0097] If the second bending moment exceeds the preset bending moment threshold, the luffing trolley is prohibited from luffing to the far end of the boom.

[0098] In one example, the preset bending moment threshold can be 90% of the maximum bending moment.

[0099] In the embodiments of this application, if the lifting bending moment is equal to the set bending moment, the same treatment can be performed as if the bending moment is less than the set bending moment, or the same treatment can be performed as if the bending moment is greater than the set bending moment.

[0100] After determining the target location of the moving counterweight (e.g., the first target location, the second target location), the moving counterweight can be controlled to move to the target location.

[0101] Specifically, in this embodiment, the upper structure may be equipped with a drive mechanism for driving the movable counterweight to move along the guide rail. In one example, the drive mechanism may include a motor, a reducer, a brake, a drum, and a pulley block. The motor may include, for example, a stepper motor or a servo motor. The motor can be connected to the drum via the reducer to drive the drum to rotate. A pull rope may be wound on the drum, one end of which can be connected to one side of the movable counterweight, and the other end can pass through the pulley block and be connected to the other side of the movable counterweight. The brake is used to brake (decelerate or stop) the drum. The reciprocating motion of the movable counterweight on the guide rail is achieved by driving the drum to rotate forward or backward by the motor.

[0102] After determining the target position (e.g., a first target position, a second target position), the distance the moving counterweight (e.g., from the initial position) needs to move to the target position can be determined. The control drive mechanism then moves the moving counterweight along the guide rail by that distance, thus reaching the target position. Taking a stepper motor as an example, after determining the distance the moving counterweight needs to move to the target position, the processor can convert that distance into an angular displacement that the stepper motor needs to perform, and output a corresponding control signal to the motor to drive it to rotate by that angular displacement. In one example, a position sensor (e.g., an encoder or a ranging sensor) can be used to detect the distance the moving counterweight has moved, enabling closed-loop control of the movement of the moving counterweight.

[0103] Accordingly, in this application embodiment, a processor is provided, configured to execute the control method for tower cranes of any of the above embodiments.

[0104] In one application scenario, the control method of the above embodiments can be executed by the tower crane controller of the tower crane. In other application scenarios, the control method of the above embodiments can be executed by an entity other than the tower crane controller. In one example, the control method can be executed by a separate processor. In this case, the processor can communicate with the tower crane controller (e.g., via a communication module). After the moving counterweight has moved to the target position, the processor can send a signal to the tower crane controller allowing the lifting operation. Upon receiving the signal, the tower crane controller can issue a notification that the lifting operation is permitted (e.g., through sound, light, or displaying relevant information on a screen in the tower crane operator's cab). In one possible application, the processor can be integrated into the drive mechanism, or it can be the motor controller of the drive mechanism.

[0105] Figure 3 A schematic block diagram of a control device for a tower crane according to an embodiment of this application is shown. Figure 3As shown in the embodiments of this application, a control device for a tower crane is provided. The tower crane may include a hinged tower body and a superstructure. The superstructure may include a counterweight boom, a jib boom, a fixed counterweight, and a movable counterweight. The fixed counterweight may be fixed to the counterweight boom side. The superstructure is provided with a guide rail extending from the counterweight boom side to the jib boom side. The movable counterweight can move along the guide rail. The control device may include:

[0106] Drive mechanism 312 is used to drive the movable counterweight to move along the guide rail, and

[0107] The processor 314 in any of the above embodiments.

[0108] Figures 4A-4E A schematic block diagram of a drive mechanism according to an embodiment of this application is shown. Figures 4A-4E As shown, specifically in a particular embodiment of this application, the upper assembly may include a guide wheel 41 disposed on the movable counterweight 4 and moving in cooperation with the guide rail.

[0109] In this embodiment of the application, the upper structure can be a truss structure, which includes an upper truss structure and a lower truss structure arranged vertically. The upper truss structure has a channel for the movement of the movable counterweight 4, and the upper truss structure includes two parallel upper chords 51. The bottom of the upper chords 51 is a lower cover plate 52. The flanges of the two lower cover plates 52 extend inward to form guide rails. The guide wheels 41 are symmetrically arranged on the left and right sides of the movable counterweight 4.

[0110] In this embodiment of the application, the upper truss structure and the lower truss structure are connected by a pin 53.

[0111] In this embodiment, the drive mechanism 312 may include a winch 6, a first pulley block, and a second pulley block. The first pulley block is mounted on the lifting arm 1, and the second pulley block is mounted on the counterweight arm 2. The winch 6 is connected to one end of the movable counterweight 4 via a traction rope that passes around the first pulley block, and the winch 6 is connected to the other end of the movable counterweight 4 via another traction rope that passes around the second pulley block, so that the winch 6 can simultaneously release the other traction rope while winding up one traction rope, thereby driving the movable counterweight 4 to move.

[0112] In this embodiment, the first pulley group includes a first pulley 71 and a second pulley 72. The first pulley 71 is installed on the inner surface of the top of the upper truss structure of the lifting arm 1, and the second pulley 72 is installed on the pin 53 between the upper truss structure and the corresponding lower truss structure. One end of a traction rope is connected to the winch 6, and the other end passes through the second pulley 72 and the first pulley 71 in sequence and is connected to one end of the moving counterweight 4. The second pulley group includes a third pulley 73 and a fourth pulley 74. The third pulley 73 is installed on the inner surface of the top of the upper truss structure of the counterweight arm 2, and the fourth pulley 74 is installed on the pin 53 located between the upper truss structure and the corresponding lower truss structure. One end of another traction rope is connected to the winch 6, and the other end passes through the fourth pulley 74 and the third pulley 73 in sequence and is connected to the other end of the moving counterweight 4.

[0113] In this embodiment, the other end of the movable counterweight 4 is provided with a mounting base 42 for connecting to the traction rope.

[0114] In this embodiment of the application, a diagonal brace 54 is provided in the lower truss structure.

[0115] In this embodiment, the winch 6 may include a motor, a reducer, a brake, and a drum. The motor may include, for example, a stepper motor or a servo motor. The motor can be connected to the drum via the reducer to drive the drum to rotate. A traction rope may be wound on the drum, and the traction rope is connected to the moving counterweight 4 as described above. The brake is used to brake the drum (decelerate or stop it). The reciprocating motion of the moving counterweight on the guide rail is achieved by driving the drum to rotate forward or backward by the motor, and the moving speed of the moving counterweight 4 can be controlled by controlling the speed of the motor.

[0116] In a preferred embodiment of this application, the control device may further include: a position detection device 316 for detecting the position of the moving counterweight.

[0117] Specifically, the position detection device can be implemented in various forms. In one example, the position detection device may include an encoder, examples of which may include, but are not limited to, absolute encoders and incremental encoders. The encoder can be configured to detect the angular displacement (e.g., number of revolutions) of a motor or reducer, determine the angular displacement of the drum based on the angular displacement of the motor or reducer, and thus determine the length of rope winding or unwinding on the drum. Alternatively, the encoder can be configured to detect the angular displacement of the drum to determine the length of rope winding or unwinding on the drum. Based on this length, the distance the moving counterweight has moved (e.g., relative to its initial position) can be determined to determine the position of the moving counterweight. In another example, the position detection device may include a distance sensor (e.g., a laser distance sensor). The distance sensor can be positioned appropriately, such as at either end of a guide rail. The distance of the moving counterweight relative to the distance sensor can be detected by the distance sensor to determine the position of the moving counterweight. In one example, the encoder or distance sensor can also be used to detect the speed at which the moving counterweight moves.

[0118] In this embodiment of the application, the control device may further include an amplitude detection device 318 (e.g., an encoder, a draw wire sensor, etc.) for detecting the amplitude of the amplitude-changing trolley.

[0119] In this application embodiment, a tower crane is provided, which may include:

[0120] Tower body;

[0121] The upper structure, hinged to the tower body, includes:

[0122] The counterweight arm is equipped with a fixed counterweight.

[0123] Crane boom; and

[0124] The mobile counterweight is equipped with a guide rail extending from the counterweight arm to the crane arm, allowing the mobile counterweight to move along the guide rail.

[0125] The control device for tower cranes in any of the above embodiments.

[0126] In this embodiment, the processor of the control device may be a tower crane controller.

[0127] Figure 5 The illustration schematically depicts a tower crane in an upward-lifting state during sudden unloading according to an embodiment of this application, showing a counterweight detachment mechanism. (See also...) Figure 5As shown, the counterweight detachment mechanism includes a traction rope 51, a pull rod 52, a counterweight support 53, a counterweight support hinge point 54, and a pull rod frame hinge point 55. The detachable counterweight 5 is installed at the mounting position of the counterweight arm 3. The detachable counterweight 5 is secured in the mounting position of the counterweight arm 3 by a pin. When the upper structure is raised, the traction rope 51 passes around the pull rod frame hinge point 55 and pulls the pull rod 52. The pull rod 52 pulls the counterweight support 53 to rotate around the counterweight support hinge point 54. The counterweight support 53 pulls the pin. When the upper structure rotates to a certain angle, this angle can be set as a second angle. That is, when the rotation angle of the upper structure reaches the second angle, the pin is pulled out from the detachable counterweight 5, thereby releasing the locking of the detachable counterweight 5 by the counterweight detachment mechanism, allowing the detachable counterweight 5 to detach from the counterweight arm 3. The upper garment continues to rotate. When the rotation angle reaches the first angle (at which point the rotation speed of the upper garment is approximately 0), the upward locking mechanism 7 locks the upper garment, preventing it from rotating further. The first angle is greater than the second angle.

[0128] Of course, the counterweight detachment mechanism is not limited to the specific structure described above, and other structural forms can also be adopted. For example, electromagnetic adsorption can be used. Specifically, an electromagnet is set on the balance arm 3, and the detachable counterweight 5 is attracted to the balance arm 3 by the electromagnet. When the power is off, the electromagnet loses its magnetism, causing the detachable counterweight 5 to detach from the balance arm 3. Alternatively, a solenoid valve is set on the balance arm 3, and the solenoid valve controls the extension and retraction of the hydraulic cylinder. The piston rod of the hydraulic cylinder is connected to a pin, and the pin passes through the structure on the balance arm 3 and is inserted into the detachable counterweight 5. When the piston rod retracts into the hydraulic cylinder, it drives the pin to be pulled out from the detachable counterweight 5, thereby releasing the lock on the detachable counterweight 5 and causing the detachable counterweight 5 to detach from the balance arm 3.

[0129] In this embodiment of the application, the tower crane can be a fixed tower crane or a mobile tower crane, and the mobile tower crane can include a crawler tower crane.

[0130] In this application embodiment, a machine-readable storage medium is provided, on which instructions are stored, which, when executed by a processor, cause the processor to implement the control method for tower cranes described in any of the above embodiments.

[0131] The above-described solution in this application determines the target position of the moving counterweight based on at least the lifting bending moment. The moving counterweight is then moved to the target position. When the tower crane experiences sudden unloading, the bending moment of the superstructure after the fixed counterweight falls off causes the jib to tend to rotate downwards, thus suppressing the jib from rising and absorbing kinetic energy. Furthermore, during normal lifting, the bending moment of the superstructure also causes the jib to tend to rotate downwards, ensuring that the superstructure does not rise during normal lifting. This improves the tower crane's resistance to overturning during sudden unloading, which is particularly important in the application of crawler tower cranes.

[0132] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0133] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0134] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0135] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0136] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0137] Memory may include non-persistent memory in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, like read-only memory (ROM) or flash RAM. Memory is an example of computer-readable media.

[0138] Computer-readable media includes both permanent and non-permanent, removable and non-removable media that can store information using any method or technology. Information can be computer-readable instructions, data structures, modules of programs, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic magnetic disk storage or other magnetic storage devices, or any other non-transferable medium that can be used to store information accessible by a computing device. As defined herein, computer-readable media does not include transient computer-readable media, such as modulated data signals and carrier waves.

[0139] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0140] The above are merely embodiments of this application and are not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. A control method for a tower crane, characterized in that, A tower crane includes a hinged tower body and a superstructure. The superstructure includes a counterweight boom, a jib, a fixed counterweight, and a movable counterweight. The fixed counterweight is fixed to the side of the counterweight boom. The superstructure is provided with a guide rail extending from the side of the counterweight boom to the side of the jib. The movable counterweight is movable along the guide rail. The control method includes: Determine the lifting bending moment of the tower crane; The first target position of the moving counterweight is determined based on at least the aforementioned lifting bending moment; and Control the moving counterweight to move to the first target position; When the mobile counterweight is located at the first target position, in the event of a sudden unloading of the tower crane, after at least a portion of the fixed counterweight falls off, the first bending moment of the superstructure relative to the hinge point between the superstructure and the tower body causes the boom to tend to rotate downwards.

2. The control method according to claim 1, characterized in that, The determination of the lifting bending moment of the tower crane includes: Obtain the weight and lifting position of the object being lifted; The lifting moment of the tower crane is determined based on the weight of the object being lifted and the lifting position.

3. The control method according to claim 1, characterized in that, The hinge point is located on the side of the balance arm.

4. The control method according to claim 3, characterized in that, At least a portion of the fixed counterweight detaches when the lifting boom is raised relative to the hinge point.

5. The control method according to claim 1, characterized in that, When the moving counterweight is at the first target position, and the tower crane is lifting the load, the first bending moment relative to the hinge point causes the boom to tend to rotate downwards.

6. The control method according to claim 1, characterized in that, Also includes: Compare the lifting bending moment with the set bending moment; Determining the first target position of the moving counterweight based on at least the lifting bending moment includes: when the lifting bending moment is greater than the set bending moment, determining the first target position of the moving counterweight based on at least the lifting bending moment.

7. The control method according to claim 6, characterized in that, Also includes: If the lifting bending moment is less than the set bending moment, then the second target position is determined based on the lifting bending moment; as well as Control the moving counterweight to move to the second target position; Specifically, when the moving counterweight is located at the second target position, and the tower crane is lifting the load, the second bending moment of the upper structure is located on the side of the crane boom.

8. The control method according to claim 7, characterized in that, The lifting boom is equipped with a luffing trolley that moves along the lifting boom, and the control method further includes: If the second bending moment exceeds a preset bending moment threshold, the luffing trolley is prohibited from luffing to the far end of the boom.

9. The control method according to claim 1, characterized in that, Determining the first target position of the moving counterweight based on the lifting bending moment includes: The lifting bending moment is input into a predetermined position determination model to obtain the first target position.

10. The control method according to claim 9, characterized in that, The location determination model is obtained through the following steps: Obtain simulation data for the tower crane, wherein the simulation data includes at least two of the following: lifting weight, lifting boom, and lifting moment, as well as the optimal position of the moving counterweight corresponding to the lifting moment. Using at least two of the lifting weight, lifting boom, and lifting bending moment as independent variables, and the optimal position of the moving counterweight as the dependent variable, data fitting is performed. If the fitted data is distributed linearly or regularly, then the fitted function is obtained to determine the location model. If the fitted data is distributed in a non-linear mapping relationship, then a neural network is used to fit the simulation data to obtain the location determination model; The position determination model is verified by inputting at least two of the lifting weight, lifting boom, and lifting bending moment into the position determination model, along with the position of the moving counterweight output by the position determination model. If the location determination model fails the verification, a mapping table is formed based on the simulation data, which maps at least two of the load weight, load arm, and load bending moment to the position of the moving counterweight. The location determination model is then obtained based on the mapping table and the interpolation function.

11. A processor, characterized in that, It is configured to perform the control method for a tower crane according to any one of claims 1 to 10.

12. A control device for a tower crane, characterized in that, A tower crane includes a hinged tower body and a superstructure. The superstructure includes a counterweight boom, a jib, a fixed counterweight, and a movable counterweight. The fixed counterweight is fixed to the side of the counterweight boom. The superstructure is provided with a guide rail extending from the side of the counterweight boom to the side of the jib. The movable counterweight is movable along the guide rail. The control device includes: A drive mechanism is used to drive the movable counterweight to move along the guide rail, and The processor according to claim 11.

13. The control device according to claim 12, characterized in that, Also includes: A position detection device is used to detect the position of the moving counterweight.

14. A tower crane, characterized in that, include: Tower body; The upper structure, hinged to the tower body, includes: The counterweight arm is equipped with a fixed counterweight. Crane boom; and A mobile counterweight is provided with a guide rail extending from the counterweight arm side to the lifting arm side, and the mobile counterweight can move along the guide rail. The control device for a tower crane according to claim 12 or 13.

15. The tower crane according to claim 14, characterized in that, The hinge point between the upper structure and the tower body is located on the side of the counterweight arm.

16. The tower crane according to claim 14, characterized in that, The tower cranes include crawler tower cranes.

17. A machine-readable storage medium, characterized in that, The machine-readable storage medium stores instructions that, when executed by a processor, cause the processor to implement the control method for a tower crane according to any one of claims 1 to 10.

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