Tower crane sudden unloading anti-overturning system, control method and processor

Abstract

The present invention discloses a tower crane sudden unloading anti-overturning system and a control method thereof, wherein the anti-overturning system includes a boom hinged to a tower body; a detachable counterweight provided on the boom; a counterweight detaching mechanism, wherein the counterweight detaching mechanism locks the detachable counterweight on the boom in a locked state and releases the lock on the detachable counterweight in a released state so that the detachable counterweight can fall off the boom; and an upward locking mechanism, wherein the upward locking mechanism connects the tower body and the boom and is used to lock the boom when the rotation angle of the boom reaches a first angle. The tower crane sudden unloading anti-overturning system of the present invention can reduce the unbalanced bending moment of the entire tower crane in the event of sudden unloading, reduce the possibility of the tower crane overturning, mitigate the impact of sudden unloading on the structure by raising the boom and shedding the counterweight, limit the boom from rotating in the opposite direction, and prevent the boom's gravitational potential energy from being released again and causing a secondary impact on the tower body.

Description

Technical Field

[0001] The present invention relates to a tower crane anti-overturning device, and more particularly to a tower crane sudden unloading anti-overturning system, and also to a tower crane sudden unloading anti-overturning system control method and processor. Background Art

[0002] Tower cranes, as key equipment in modern construction, are widely used in building, wind power, and nuclear power construction. In some specialized industries, customers are particularly concerned about preventing secondary damage caused by tower crane overturning, and their requirements for tower crane anti-overturning are becoming increasingly stringent.

[0003] Currently, tower crane anti-overturning measures primarily rely on adjusting the overall mass distribution and strengthening the tower body, based on the traditional tower crane structure, to improve the crane's anti-overturning performance. However, as tower cranes develop towards larger and heavier loads, these anti-overturning designs become less effective. This is especially true for ultra-large tower cranes, which face sudden unloading, where simply adjusting the structural mass and strength makes it difficult to achieve anti-overturning performance.

[0004] Therefore, the sudden unloading and anti-overturning design of super-large tower cranes has always been a technical difficulty in this industry. Summary of the Invention

[0005] The technical problem to be solved by this invention is to provide a tower crane sudden unloading anti-overturning system that can reduce the unbalanced bending moment of the entire tower crane during sudden unloading, thereby reducing the possibility of the tower crane overturning. By raising the boom and using a removable counterweight, the impact of sudden unloading on the structure is mitigated, and the boom's reverse rotation is restricted, preventing the boom's gravitational potential energy from being released again and causing a secondary impact on the tower body.

[0006] The technical problem that the present invention also aims to solve is to provide a control method for a tower crane's sudden unloading anti-overturning system. The control method for a tower crane's sudden unloading anti-overturning system reduces the impact of sudden unloading on the structure by raising the boom and using a detachable counterweight, limits the boom's reverse rotation, and avoids the boom's gravitational potential energy being released again to cause a secondary impact on the tower body.

[0007] In order to solve the above technical problems, the present invention provides a tower crane sudden unloading anti-overturning system, the anti-overturning system includes:

[0008] Tower body;

[0009] A boom, the boom being hinged to the tower body;

[0010] a detachable counterweight, the detachable counterweight being arranged on the arm;

[0011] a counterweight dropping mechanism, wherein the counterweight dropping mechanism locks the detachable counterweight on the arm in a locked state and releases the lock on the detachable counterweight in a released state so that the detachable counterweight can drop from the arm;

[0012] An upward locking mechanism is connected to the tower body and the boom, and is used to lock the boom when the rotation angle of the boom reaches a first angle.

[0013] Optionally, the boom includes a lifting arm and a balancing arm;

[0014] The detachable balancing weight is arranged on the balancing arm.

[0015] Furthermore, it also includes a movable counterweight, wherein the movable counterweight is connected to the arm;

[0016] A displacement drive mechanism is used to drive the movable counterweight to move on the arm.

[0017] Furthermore, the arm support is provided with a guide rail extending from the balance arm to the lifting arm, and the movable balance weight is slidably connected to the guide rail.

[0018] Optionally, the hinge point between the arm and the tower body is located on a side of the tower body close to the balance arm, and the connection portion between the upward locking mechanism and the tower body is located on a side of the tower body close to the lifting arm.

[0019] Furthermore, the upward locking mechanism includes a double-rod hydraulic cylinder, a hydraulic rod at one end of the double-rod hydraulic cylinder is pivotally connected to the side of the tower body close to the lifting arm, and a hydraulic rod at the other end is connected to the arm frame, and the hydraulic rods at both ends of the double-rod hydraulic cylinder extend and retract synchronously.

[0020] Furthermore, the hydraulic rod at one end of the double-rod hydraulic cylinder is pivotally connected to a side of the tower body close to the lifting arm through a pin.

[0021] Optionally, the counterweight detaching mechanism is configured to release the lock on the detachable counterweight when the rotation angle of the arm reaches a second angle, and the second angle is smaller than the first angle.

[0022] Another aspect of the present invention provides a control method for a tower crane sudden unloading anti-overturning system. The control method comprises:

[0023] Get the arm's rotation angle;

[0024] When the rotation angle reaches a first angle, the upward locking mechanism is controlled to lock the arm.

[0025] Optionally, after obtaining the rotation angle of the boom, the method further includes:

[0026] When the rotation angle reaches a second angle, the counterweight dropping mechanism is controlled to release the lock on the detachable counterweight.

[0027] Optionally, when the tower crane sudden unloading anti-overturning system further includes moving a counterweight, the method further includes:

[0028] Under normal hoisting conditions, the target position of the mobile counterweight on the boom is determined at least according to the load moment.

[0029] Optionally, determining a target position of the mobile counterweight on the boom includes:

[0030] Obtaining the weight and hoisting position of the hoisted object to determine the load moment of the tower crane;

[0031] The target position of the mobile counterweight is determined based on at least the load moment, the mobile counterweight is controlled to move to the target position, and the boom bending moment acting on the boom causes the boom to tend to rotate downward relative to the hinge point between the boom and the tower body.

[0032] Optionally, obtaining load torque and load status;

[0033] When the hoisting state is normal hoisting and the load torque is greater than a preset torque, controlling the upward locking mechanism to lock the boom;

[0034] When the hoisting state is normal hoisting and the load torque is less than or equal to a preset torque, controlling the upward locking mechanism to unlock the boom;

[0035] When the rotation angle reaches the first angle, controlling the upward locking mechanism to lock the arm comprises:

[0036] When the hoisting state is a sudden unloading state and the rotation angle reaches the first angle, the upward locking mechanism is controlled to lock the boom.

[0037] The present invention also provides a processor configured to execute the tower crane sudden unloading anti-overturning system control method described in any one of the above technical solutions.

[0038] Through the above technical solution, the beneficial effects of the present invention are as follows:

[0039] When the tower crane is suddenly unloaded, the boom rises, converting the resulting impact bending moment into the boom's rotational kinetic energy. This rotational kinetic energy is then converted into the boom's gravitational potential energy, achieving the purpose of absorbing energy during the boom's upward movement. The boom's rotation angle reaches a first angle, at which point the upward locking mechanism locks the boom to prevent the boom's increased gravitational potential energy from being released and impacting the tower. When the boom rises to a certain angle, the counterweight dropout mechanism causes the detachable counterweight to fall off the boom, removing the counterweight's potential energy. This, in turn, reduces and reverses the unbalanced bending moment of the entire tower crane, minimizing the possibility of the crane tipping over.

[0040] Other features and advantages of the present invention will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the following detailed description, they are used to explain the present invention but do not constitute a limitation of the present invention. In the accompanying drawings:

[0042] Figure 1 2 is a schematic structural diagram of a tower crane sudden unloading anti-overturning system in a specific embodiment of the present invention, with the boom in an upward state;

[0043] Figure 2 This is a schematic diagram of the structure in which the lifting mechanism and the lifting locking mechanism in a specific embodiment of the present invention are installed between the boom and the tower body;

[0044] Figure 3 It is a structural schematic diagram of the lifting mechanism in a specific embodiment of the present invention;

[0045] Figure 4 1 is a schematic structural diagram of a tower crane sudden unloading anti-overturning system in a specific embodiment of the present invention, wherein the boom is in a horizontal state;

[0046] Figure 5 is a structural schematic diagram of a mobile counterweight mechanism in a specific embodiment of the present invention;

[0047] Figure 6 This is a simplified diagram of the tower crane state when the anti-overturning system in a specific embodiment of the present invention is in effect;

[0048] Figure 7 It is a flowchart of a tower crane sudden unloading anti-overturning system control method in a specific embodiment of the present invention.

[0049] Description of Reference Numerals

[0050] 1 tower body 2 mobile counterweight

[0051] 21 pulley 22 winch

[0052] 3 balance arms 4 lifting arms

[0053] 5 detachable counterweight 51 traction rope

[0054] 52 pull rod 53 balance weight support

[0055] 54 counterweight support hinge point 55 tie rod frame hinge point

[0056] 61 hinge point 62 pin

[0057] 7 Upward locking mechanism DETAILED DESCRIPTION

[0058] The specific embodiments of the present invention are described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention, and the scope of protection of the present invention is not limited to the specific embodiments described below.

[0059] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "disposed," "installed," and "connected" should be understood broadly. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to direct connections or indirect connections through an intermediate medium; they may refer to internal communication between two components or the interaction between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0060] In addition, the terms "first", "second", etc. are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, features defined as "first", "second", etc. may explicitly or implicitly include one or more of the said features.

[0061] In the description of the present invention, it should be understood that the orientation terms are based on the orientation of the tower crane in use. In order to facilitate the description of the present invention and simplify the description, the terms "front" and "rear" refer to the up and down directions of the tower crane in actual use. For example, Figure 1 , the boom 4 is located in front of the balance arm 3; the orientations or positional relationships shown in the drawings are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore should not be understood as limiting the present invention.

[0062] like Figures 1 to 4As shown, the present invention provides a sudden unloading anti-overturning system for a tower crane, the anti-overturning system comprises a tower body 1, a boom, a detachable counterweight 5, a counterweight detaching mechanism and an upward locking mechanism 7, the boom is hinged to the tower body 1, a detachable counterweight 5 is arranged on the boom, and the upward locking mechanism 7 is connected between the tower body 1 and the boom. Under normal hoisting conditions, the counterweight detaching mechanism locks the detachable counterweight 5 on the boom, so that the detachable counterweight 5 is in a locked state; when the tower crane is suddenly unloaded, the upward locking mechanism 7 releases the lock on the boom, allowing the boom to rise, and when the boom is rotated to a certain angle The counterweight falling-off mechanism releases the lock on the detachable counterweight 5, so that the detachable counterweight 5 is in a released state, and the detachable counterweight 5 falls off from the boom, reducing the unbalanced bending moment of the entire tower crane and reducing the possibility of overturning the tower crane; in the process of the boom rising, the boom can convert the generated impact bending moment into rotational kinetic energy, and then convert the rotational kinetic energy into the gravitational potential energy of the boom, to avoid the impact bending moment being transmitted to the tower body 1. When the rotation angle of the boom reaches the first angle, the upward locking mechanism 7 will lock the boom again to prevent the increased gravitational potential energy of the boom from being converted into rotational kinetic energy again, forming an impact load on the tower body 1.

[0063] Generally, the boom includes a lifting arm 4 and a balancing arm 3, with a detachable counterweight 5 disposed on the balancing arm 3. Preferably, the detachable counterweight 5 is disposed at the tail end of the balancing arm 3. Furthermore, a movable counterweight 2 may be disposed on the boom, and the movable counterweight 2 is connected to a displacement drive mechanism, which is used to drive the movable counterweight 2 to move on the boom.

[0064] As a specific embodiment of the balance weight falling mechanism, Figure 1 As shown, the counterweight detachment mechanism includes a traction rope 51, a pull rod 52, a counterweight support 53, a counterweight support hinge 54 and a pull rod frame hinge 55. The detachable counterweight 5 is installed in the installation position of the balance arm 3, and the detachable counterweight 5 is clamped in the installation position of the balance arm 3 through a pin. When the arm is raised, the traction rope 51 passes around the pull rod frame hinge 55 to pull the pull rod 52, and the pull rod 52 pulls the counterweight support 53 to rotate around the counterweight support hinge 54, and the counterweight support 53 pulls the pin. When the arm rotates to a certain angle, the angle can be set to a second angle, that is, when the rotation angle of the arm reaches the second angle, the pin is pulled out from the detachable counterweight 5, so that the counterweight detachment mechanism releases the lock on the detachable counterweight 5, allowing the detachable counterweight 5 to fall off from the balance arm 3. The arm continues to rotate, and when the rotation angle reaches a first angle (at this time, the rotation speed of the arm is approximately 0), the upward locking mechanism 7 locks the arm so that it no longer rotates, wherein the first angle is greater than the second angle.

[0065] Of course, the balancing weight falling-off mechanism is not limited to the above-mentioned specific structure, and other structural forms may also be adopted. For example, electromagnetic adsorption may be adopted. Specifically, an electromagnet is provided on the balancing arm 3, and the detachable balancing weight 5 is adsorbed on the balancing arm 3 by the electromagnet. When the power is off, the electromagnet loses its magnetism, causing the detachable balancing weight 5 to fall off from the balancing arm 3; or, a solenoid valve is provided on the balancing arm 3, and the solenoid valve controls the extension and retraction of the oil cylinder. The piston rod of the oil cylinder is connected to the pin shaft, and the pin shaft passes through the structure on the balancing arm 3 and is inserted into the detachable balancing weight 5. When the piston rod retracts into the oil cylinder, the pin shaft is driven to be pulled out of the detachable balancing weight 5, thereby releasing the lock on the detachable balancing weight 5 and causing the detachable balancing weight 5 to fall off from the balancing arm 3.

[0066] As a specific embodiment of the upward locking mechanism 7, Figure 2 As shown, the upward locking mechanism 7 includes a double-rod hydraulic cylinder. The hydraulic rod at one end of the double-rod hydraulic cylinder is pivotally connected to the side of the tower body 1 near the lifting arm 4, and the hydraulic rod at the other end is connected to the boom. The hydraulic rods at both ends of the double-rod hydraulic cylinder extend and retract synchronously. The double-rod hydraulic cylinder is connected to a hydraulic control system, which controls the movement of the double-rod hydraulic cylinder. When the upward locking mechanism 7 locks the boom, the hydraulic control system controls the hydraulic rods at both ends of the double-rod hydraulic cylinder to remain stationary. When the upward locking mechanism 7 releases the boom, the hydraulic control system controls the hydraulic rods at both ends of the double-rod hydraulic cylinder to move synchronously. Alternatively, the upward locking mechanism 7 can also use an electromechanical PID control system in conjunction with a wedge mechanism, a ratchet mechanism, or a hydraulic mechanism to achieve a comparative locking function.

[0067] Furthermore, if Figure 2 and Figure 3 As shown, the hinge point 61 between the arm and the tower body 1 is located on the side of the tower body 1 close to the balance arm 3, and the upward locking mechanism 7 is connected to the tower body 1 through a pin 62. The pin 62 is located on the side of the tower body 1 close to the lifting arm 4. The hinge point 61 and the pin 62 constitute an upward mechanism.

[0068] In a specific embodiment of the present invention, a guide rail is provided on the boom, and the guide rail extends from the balance arm 3 to the lifting arm 4, and the mobile counterweight 2 is slidably installed on the guide rail. Specifically, a luffing trolley can be installed on the guide rail, and the mobile counterweight 2 is hung under the luffing trolley, and the mobile counterweight 2 is driven to move by driving the luffing trolley. Adjusting the position of the mobile counterweight 2 on the balance arm 3 and the lifting arm 4 can improve the bending moment state of the whole machine during normal lifting, reduce the bending moment of the tower crane body, and reduce the potential energy stored in the tower body during sudden unloading. After the tower crane is suddenly unloaded, the mobile counterweight 2 is located on the lifting arm 4, which can suppress the lifting arm 4 from rising, so that the rotational kinetic energy of the boom is converted into gravitational potential energy, thereby achieving the purpose of absorbing kinetic energy.

[0069] As a specific structural form of displacement drive mechanism, such as Figure 5As shown, the displacement drive mechanism includes a pulley 21 and a winch 22. The winch 22 is installed on the arm. A channel is set in the arm for the mobile counterweight 2 to pass through. The winch 22 passes through the pulley 21 on one side through a steel wire rope and is connected to the mounting seat on one side of the mobile counterweight 2. The winch 22 passes through the pulley 21 on the other side through another steel wire rope and is connected to the mounting seat on the other side of the mobile counterweight 2; in the process of pulling the mobile counterweight 2 to move, the winch 22 releases one steel wire rope while synchronously reeling in the other steel wire rope, thereby controlling the mobile counterweight 2 to move at a uniform and stable speed.

[0070] like Figure 7 As shown, based on the tower crane sudden unloading anti-overturning system, the present invention also provides a tower crane sudden unloading anti-overturning system control method, the control method includes:

[0071] Get the arm's rotation angle;

[0072] When the rotation angle reaches the first angle, the upward locking mechanism 7 is controlled to lock the boom. When the boom's rotation angle reaches the first angle, the boom's rotation speed is approximately 0, that is, the boom is raised to its maximum angle position. At this time, the upward locking mechanism 7 is controlled to lock the boom, which can prevent the boom's gravitational potential energy from being converted into rotational kinetic energy again, thereby causing an impact on the tower body 1.

[0073] Furthermore, after obtaining the boom's rotation angle, when the boom's rotation angle reaches a second angle, the counterweight dropping mechanism is controlled to release the lock on the detachable counterweight 5. The second angle is smaller than the first angle, and when the boom rotates to the second angle, the counterweight dropping mechanism can be triggered to release the lock on the detachable counterweight 5, allowing the detachable counterweight 5 to fall off the boom, thereby reducing the unbalanced bending moment of the entire tower crane and reducing the possibility of the tower crane overturning.

[0074] In an embodiment of the present invention, when the anti-overturning system of the tower crane is suddenly unloaded and includes a mobile counterweight 2, the mobile counterweight 2 is installed on the boom and can move along the length direction of the boom. Under normal loading conditions, the target position of the mobile counterweight 2 on the boom is determined based on at least the load torque, thereby balancing the bending moment exerted on the entire tower crane.

[0075] Furthermore, the weight of the hoisted object is obtained to determine the load torque of the tower crane; specifically, the weight of the hoisted object applied to the boom can be detected by a weight detection device. For example, an example of a weight detection device may include a weighing sensor, which can be set at the hook to detect the weight of the hoisted object. The position of the luffing trolley (i.e., the distance of the luffing trolley along the boom from the tower crane's rotation center) can be detected by a position sensor (such as a rotary encoder or a cable sensor) to determine the gravity of the hoisted object relative to the lever arm of the tower crane's rotation center (the position of the tower crane's rotation center is known), and the load torque of the hoisted object can be determined based on the weight and lever arm of the hoisted object.

[0076] The target position of the mobile counterweight 2 is determined based on at least the load torque, and the mobile counterweight 2 is controlled to move to the target position, while the boom bending moment acting on the boom is biased toward the boom relative to the hinge point 61 between the boom and the tower body. The boom bending moment acting on the boom causes the boom to rotate downward relative to the hinge point 61 between the boom and the tower body, that is, to tilt slightly forward. During normal loading, this reduces the unbalanced bending moment of the entire tower crane and increases the redundant design space of the tower body. In the event of a sudden unloading of the tower crane and the detachable counterweight 5, the boom bending moment can suppress the upward movement of the boom 4, thereby absorbing kinetic energy.

[0077] In the embodiment of the present invention, the hoisting conditions can be divided into two categories. One category is when the load moment is less than a set value (which can be considered as a small hoisting condition), the tower crane is strong enough to withstand (hard-resist) the sudden unloading condition. Only by moving the counterweight 2, the overall bending moment state of the boom can be changed to improve the tower crane's hard-resistance to sudden unloading. The target position of the mobile counterweight 2 on the boom is determined according to the load moment. During normal hoisting, the position of the mobile counterweight 2 is adjusted, and the boom bending moment is tilted forward as much as possible, so that when the tower crane is suddenly unloaded, the forward bending moment can offset the impact bending moment of the sudden unloading, thereby achieving the effect of improving the hard-resistance to sudden unloading condition. The other category is when the load moment is greater than the set value (which can be considered as a large hoisting condition), the tower body strength is not enough to hard-resist the sudden unloading condition. At this time, the mobile counterweight 2 and the detachable counterweight 5 need to work together to prevent the tower crane from overturning.

[0078] Furthermore, simulation software (e.g., commercial simulation software) can be used to model the tower crane to be studied, i.e., to establish a simulation model of the tower crane. A computational model of the boom and tower flexible body is established, and modal information of the boom and tower is calculated. Data fitting is performed using at least two of the load weight, load arm, and load torque as independent variables and the target position of the mobile counterweight 2 as the dependent variable. If the fitted data distribution is linear or regular, a fitting function is obtained to obtain a position determination model; if the fitted data distribution is nonlinear mapping, an intelligent algorithm (e.g., BP neural network, radial basis algorithm, etc.) is used to fit the simulation data to obtain a position determination model.

[0079] In a specific embodiment of the present invention, the control process of the upward locking mechanism 7 is as follows:

[0080] Obtain load torque and load status;

[0081] When the hoisting state is normal and the load torque is greater than the preset torque, the upward locking mechanism 7 is controlled to lock the boom; at this time, the tower crane is performing normal hoisting operations.

[0082] When the hoisting state is normal and the load torque is less than or equal to the preset torque, the upward locking mechanism 7 is controlled to release the locking arm; at this time, the tower crane is suddenly unloaded, specifically, the wire rope used for hoisting of the tower crane breaks, causing the hoisted object to fall, or the hoisted object to fall off the hook.

[0083] When the hoisting state is a sudden unloading state and the rotation angle reaches the first angle, the upward locking mechanism 7 is controlled to lock the boom. At this time, the boom is raised to the maximum angle (the rotation speed of the boom is 0). The upward locking mechanism 7 is controlled to lock the boom, which can prevent the boom from rotating downward again and causing an impact on the tower body 1.

[0084] Specifically, the rate of change of the load torque can be used to detect the degree of change in the load torque per unit time. In other words, when the load torque suddenly changes dramatically, it can be considered that the loading state has transitioned from normal loading to sudden unloading. Alternatively, the hook or rope of the tower crane can be monitored. If the load on the hook or rope of the tower crane suddenly decreases significantly or even reaches zero during normal loading, the loading state can be considered to have transitioned from normal loading to sudden unloading.

[0085] Specifically, a displacement sensor may be used to measure the lifting position of the boom, and the lifting speed of the boom may be obtained through differential calculation. Based on the lifting speed of the boom, the lifting limit angle of the boom may be determined.

[0086] like Figure 6As shown, the action process of the tower crane sudden unloading anti-overturning system of the present invention can be roughly divided into four stages, namely, normal lifting to sudden unloading, sudden unloading to the falling off of the detachable counterweight, the falling off of the detachable counterweight to the boom rising to the maximum angle, and the boom rising to the maximum angle (boom locking).

[0087] The energy change of the boom caused by the impact of broken rope during the whole process is as follows:

[0088] W1=M1×α1+(-M2)×β1

[0089] Among them, M1 represents the backward bending moment exerted on the boom, the second angle α1 represents the upward angle of the boom at the moment when the detachable counterweight 5 falls off, M2 represents the forward bending moment exerted on the boom, and β1 represents the angle of rotation of the boom from the time when the detachable counterweight 5 falls off to the time when it is locked.

[0090] During normal hoisting, the displacement drive mechanism controls the movement of the mobile counterweight 2 to the target position based on the acquired load torque. This shifts the boom bending moment acting on the boom toward the boom, improving the overall bending moment during normal hoisting and reducing the tower bending moment. This reduces the overall unbalanced bending moment and increases the redundancy design space of the tower. Furthermore, it reduces the elastic potential energy stored in the tower during sudden unloading, thereby reducing M1 and α1 after the tower crane is suddenly unloaded.

[0091] After the sudden unloading occurs and before the detachable counterweight falls off, due to the large backward bending moment M1 of the boom, the upward locking mechanism 7 releases the lock on the boom, releasing the rotational freedom of the boom. Under the action of the backward bending moment M1, the boom rotates upward, and the backward bending moment M1 is converted into the rotational kinetic energy of the boom, preventing the backward bending moment M1 from being transmitted to the tower body, causing the tower body to bear a large backward bending moment M1.

[0092] Before the detachable counterweight falls off until the boom is raised to its maximum angle (the boom is locked), when the boom rotates to the second angle α1, the counterweight shedding mechanism releases the lock on the detachable counterweight 5, allowing the detachable counterweight 5 to fall off the boom, removing the counterweight's gravitational potential energy. At this time, the boom bending moment changes from the backward bending moment M1 to a slightly forward bending moment M2. The forward bending moment M2 will prevent the boom from continuing to rise, converting the boom's rotational kinetic energy into the boom's gravitational potential energy, thereby absorbing energy. In this process, the energy conversion process is the conversion of the sudden unloading impact energy into the boom's rotational kinetic energy of rising. After the detachable counterweight falls off, the boom's rotational kinetic energy is converted into the boom's gravitational potential energy, achieving the purpose of the boom rising to absorb the sudden unloading impact energy.

[0093] The boom is raised to its maximum angle (boom locking). When the boom is raised to the first angle (i.e., the maximum position θ1, at which the upward angular velocity is approximately 0), the bending moment is the forward bending moment M2. The upper locking mechanism 7 locks the boom in this position to prevent the boom from falling back and hitting the tower body (the gravitational potential energy is released as rotational kinetic energy), causing a secondary impact and ensuring the stability of the entire tower crane structure.

[0094] In some large and even extra-large tower crane applications (for example, those used in wind power and nuclear power facilities), particularly in crawler-type tower cranes, the load and the counterweights used to match the load can be very heavy. During the lifting process, the moment on the counterweight side varies significantly, and the moment acting on the tower is also very high. To ensure safety, the traditional approach is to adjust the overall mass distribution and enhance the tower strength to improve the crane's anti-overturning performance. However, for large and even extra-large tower cranes, simply adjusting the structural mass and strength to achieve anti-overturning performance is unrealistic.

[0095] The present invention designs a control strategy for the mobile counterweight 2 and the detachable counterweight 5. During normal hoisting, by adjusting the position of the mobile counterweight 2 on the boom, the bending moment state of the entire machine during normal hoisting can be improved, the bending moment of the tower crane body can be reduced, and the potential energy stored in the tower body during sudden unloading can be reduced. During sudden unloading, the boom rises, converting the backward bending moment into rotational kinetic energy to prevent the backward bending moment from being transmitted to the tower body. When the boom rotates to a second angle, the counterweight shedding mechanism controls the detachable counterweight 5 to detach from the boom, removing the gravitational potential energy of the counterweight, while reducing the unbalanced bending moment of the entire tower crane and the possibility of the tower crane overturning. After the detachable counterweight 5 falls off, the bending moment on the boom changes from the backward bending moment to the forward bending moment, allowing the boom to absorb energy by increasing its own gravitational potential energy. When the boom rises to the maximum angle, the upward locking mechanism 7 locks the boom to prevent the gravitational potential energy stored in the boom from being released again to impact the tower body, thereby achieving the purpose of preventing the tower crane from overturning.

[0096] In an embodiment of the present invention, a processor is provided, configured to execute the method for controlling a tower crane sudden unloading anti-overturning system according to any of the above embodiments.

[0097] The preferred embodiments of the present invention are described in detail above in conjunction with the accompanying drawings. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, various simple modifications can be made to the technical solution of the present invention, and these simple modifications all fall within the scope of protection of the present invention.

[0098] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any appropriate manner without contradiction. To avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0099] In addition, the various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

Claims

1. A tower crane sudden unloading anti-overturning system, characterized in that: The anti-overturning system includes Tower (1); A boom, the boom being hinged to the tower body (1); A detachable counterweight (5), the detachable counterweight (5) being arranged on the arm; The counterweight dropping mechanism locks the detachable counterweight (5) on the boom when the tower crane is normally hoisting, so that the detachable counterweight (5) is in a locked state. When the tower crane is suddenly unloaded and the boom rotates to a second angle, the counterweight dropping mechanism releases the lock on the detachable counterweight (5), so that the detachable counterweight (5) is in a released state, so that the detachable counterweight (5) can fall off from the boom; An upward locking mechanism (7) is provided, wherein the upward locking mechanism (7) connects the tower body (1) and the arm and is used to lock the arm when the rotation angle of the arm reaches a first angle.

2. The tower crane sudden unloading anti-overturning system according to claim 1 is characterized in that: The boom comprises a lifting arm (4) and a balancing arm (3); The detachable balancing weight (5) is arranged on the balancing arm (3).

3. The tower crane sudden unloading anti-overturning system according to claim 2 is characterized in that: Also includes A movable counterweight (2), the movable counterweight (2) being connected to the arm; A displacement drive mechanism, wherein the displacement drive mechanism is used to drive the movable counterweight (2) to move on the arm.

4. The tower crane sudden unloading anti-overturning system according to claim 3 is characterized in that: A guide rail extending from the balancing arm (3) to the lifting arm (4) is provided on the arm frame, and the movable balancing weight (2) is slidably connected to the guide rail.

5. The tower crane sudden unloading anti-overturning system according to claim 2, characterized in that: The hinge point (61) between the arm and the tower body (1) is located on a side of the tower body (1) close to the balance arm (3), and the connection portion between the upward locking mechanism (7) and the tower body (1) is located on a side of the tower body (1) close to the lifting arm (4).

6. The tower crane sudden unloading anti-overturning system according to claim 5, characterized in that: The upward locking mechanism (7) comprises a double-rod hydraulic cylinder, wherein a hydraulic rod at one end of the double-rod hydraulic cylinder is pivotally connected to a side of the tower body (1) close to the lifting arm (4), and a hydraulic rod at the other end is connected to the boom, and the hydraulic rods at both ends of the double-rod hydraulic cylinder are synchronously extended and retracted.

7. The tower crane sudden unloading anti-overturning system according to claim 6, characterized in that: The hydraulic rod at one end of the double-rod hydraulic cylinder is pivotally connected to a side of the tower body (1) close to the lifting arm (4) through a pin shaft (62).

8. The tower crane sudden unloading anti-overturning system according to claim 1, characterized in that: The counterweight dropping mechanism is configured to release the locking of the droppable counterweight (5) when the rotation angle of the arm reaches a second angle, wherein the second angle is smaller than the first angle.

9. A tower crane sudden unloading anti-overturning system control method, characterized in that: Based on the tower crane sudden unloading anti-overturning system according to any one of claims 1 to 8, the control method includes: Get the arm's rotation angle; When the rotation angle reaches a first angle, the upward locking mechanism (7) is controlled to lock the arm.

10. The tower crane sudden unloading anti-overturning system control method according to claim 9, characterized in that: After obtaining the rotation angle of the boom, the method further includes: When the rotation angle reaches the second angle, the balancing weight dropping mechanism is controlled to release the locking of the detachable balancing weight (5).

11. The tower crane sudden unloading anti-overturning system control method according to claim 9, characterized in that: In the case where the tower crane sudden unloading anti-overturning system further includes a movable counterweight (2), the method further includes: Under normal hoisting conditions, the target position of the mobile counterweight (2) on the boom is determined at least according to the load moment.

12. The tower crane sudden unloading anti-overturning system control method according to claim 11, characterized in that: Determining the target position of the mobile counterweight (2) on the boom comprises: Obtaining the weight and hoisting position of the hoisted object to determine the load moment of the tower crane; The target position of the mobile counterweight (2) is determined based on at least the load moment, the mobile counterweight (2) is controlled to move to the target position, and the boom bending moment acting on the boom is caused to rotate downward relative to the hinge point (61) between the boom and the tower body.

13. The tower crane sudden unloading anti-overturning system control method according to claim 9, characterized in that: Obtain load torque and load status; When the hoisting state is normal hoisting and the load torque is greater than a preset torque, controlling the upward locking mechanism (7) to lock the boom; When the hoisting state is normal hoisting and the load torque is less than or equal to a preset torque, controlling the upward locking mechanism (7) to unlock the boom; When the rotation angle reaches a first angle, controlling the upward locking mechanism (7) to lock the arm comprises: When the hoisting state is a sudden unloading state and the rotation angle reaches the first angle, the upward locking mechanism (7) is controlled to lock the boom.

14. A processor, characterized in that: The method is configured to execute the tower crane sudden unloading anti-overturning system control method according to any one of claims 9 to 13.

Images