Omnidirectional active dynamic balance system of tower crane and control method

Abstract

The invention discloses an omni-directional active dynamic balance system of a tower crane and a control method. The omni-directional active dynamic balance system comprises an attitude monitoring unit, a control unit, a longitudinal balance mechanism and a transverse balance mechanism, the control unit controls the longitudinal balance mechanism and / or the transverse balance mechanism to act according to the posture deviation direction, so that the tower body keeps vertical and does not shake in the transverse direction. The method comprises the steps of real-time monitoring, deviation judgment, dynamic adjustment and closed-loop feedback. The transverse balance mechanism is independently arranged, transverse shaking is adjusted through the relative position difference of the double counterweight components, 360-degree omni-directional active dynamic balance of the tower crane is achieved for the first time, any dynamic disturbance including wind load and rotation centrifugal force can be sensed and corrected in real time, alternating bending moment borne by a tower body is eliminated, fatigue of a metal structure is delayed, and the service life of the tower crane is prolonged. And the service life of the tower crane is greatly prolonged.

Description

Technical Field

[0001] This invention relates to the field of automatic control technology for tower cranes, specifically to an omnidirectional active dynamic balancing system and control method for tower cranes. Background Technology

[0002] Tower cranes, as crucial material handling equipment in modern construction engineering, directly impact operational safety and service life through their balance performance. Traditional static counterweight methods, with their fixed balancing torque, cannot adapt to real-time changes in load weight and position. This results in the tower body enduring alternating bending moments over extended periods, causing swaying, affecting operational safety, and accelerating fatigue damage to the metal structure. To address this issue, the industry has proposed various dynamic balancing solutions. For example, patent CN104495643B's "An Active Stability Maintenance System for Tower Cranes" uses longitudinal and transverse pulleys to move the balance ellipsoid, actively changing the tower's center of gravity to achieve dynamic balance. Another example is patent CN201087088Y's "Adaptive Adjustment Device for Counterweight of Luffing Boom Tower Cranes," which uses a four-bar linkage mechanism to adaptively adjust the counterweight according to the boom's pitch movement. However, the aforementioned existing technologies mainly focus on longitudinal balance adjustment along the boom direction, and their core control logic is mostly based on torque calculation or mechanical linkage. They lack targeted solutions for the lateral swaying problem caused by factors such as lateral wind and centrifugal force during tower crane rotation.

[0003] First, as a vertical support structure, the tower crane's tower body is susceptible to significant safety hazards from any swaying. However, existing research only addresses the longitudinal balance along the boom direction, completely neglecting the risk of lateral swaying perpendicular to the boom. Furthermore, the randomness of the wind direction and the continuous, uninterrupted operation of the slewing mechanism make lateral swaying unpredictable and uncontrollable. Second, even if the solution described in CN104495643B can achieve two-dimensional counterweight movement, the balance ellipsoid experiences inertial delay as it moves along the tower crane boom. The control system still relies on point-to-point control logic based on angle detection followed by target position calculation, failing to achieve real-time continuous adjustment of lateral swaying. Additionally, existing technologies, such as the balance plate proximity switch solution disclosed in CN206407848U, only provide a switching signal for counterweight movement, with response accuracy and speed insufficient for dynamic operating conditions. Most existing control modes are open-loop, unable to provide real-time feedback and correction for dynamic disturbances. The tower body is constantly subjected to alternating bending moments, leading to significant structural fatigue issues. Therefore, how to achieve active, real-time, and continuous adjustment of the lateral sway of the tower crane and eliminate the alternating bending moment borne by the tower body has become a technical problem that urgently needs to be solved in this field. Summary of the Invention

[0004] This invention proposes an omnidirectional active dynamic balancing system and control method for tower cranes, which realizes 360° omnidirectional active dynamic balancing of tower cranes, improves operational safety and equipment service life, and solves the problem that existing tower cranes cannot simultaneously achieve real-time active dynamic balancing of longitudinal and lateral sway, resulting in metal fatigue and lateral sway safety hazards caused by alternating bending moments on the tower body.

[0005] The technical solution of this invention is implemented as follows:

[0006] A tower crane omnidirectional active dynamic balancing system includes:

[0007] The attitude monitoring unit is installed on the tower body or boom to monitor the attitude status of the tower crane in real time and output the actual attitude value.

[0008] The control unit is electrically connected to the attitude monitoring unit and is used to receive the actual attitude value, compare it with the preset standard attitude value, determine the attitude deviation and the direction of the deviation, and generate control commands.

[0009] A longitudinal balancing mechanism is located on the side of the counterweight arm and is electrically connected to the control unit. It is used to adjust the longitudinal balancing torque of the tower crane along the working arm direction according to the control command.

[0010] A lateral balancing mechanism, set independently of the longitudinal balancing mechanism, is electrically connected to the control unit and is used to adjust the lateral center of gravity position of the tower crane perpendicular to the boom direction according to the control command.

[0011] The control unit controls the longitudinal balancing mechanism and / or the lateral balancing mechanism to operate according to the attitude deviation direction fed back by the attitude monitoring unit, so that the tower body remains vertical and the lateral sway is eliminated.

[0012] Furthermore, the longitudinal balancing mechanism includes:

[0013] The third and fourth winches are located at the root and tail of the counterweight boom, respectively.

[0014] The second counterweight steel cable has its two ends connected to the third winch and the fourth winch respectively, and the second counterweight steel cable can be wound in a biased manner between the third winch and the fourth winch;

[0015] Specifically, by changing the winding length distribution of the second counterweight steel cable on the third and fourth winches, the center of gravity of the second counterweight steel cable is moved in the length direction of the counterweight arm, thereby changing the longitudinal balance torque; the second counterweight steel cable is made of multiple strands of scrapped lifting wire rope.

[0016] Furthermore, the lateral balancing mechanism includes:

[0017] A horizontal beam is fixedly installed at the top of the tower body and passes through the tower body axis, extending horizontally in a direction perpendicular to the tower crane's working arm, forming an independent lateral balance support structure.

[0018] The first movable counterweight component and the second movable counterweight component are respectively disposed at both ends of the horizontal beam, and can move independently along the length of the horizontal beam.

[0019] A drive mechanism, electrically connected to the control unit, is used to independently drive the first movable counterweight component and the second movable counterweight component to move;

[0020] Specifically, by adjusting the relative positions of the first movable counterweight component and the second movable counterweight component, a positional difference is created, causing the center of gravity of the system to shift to one side, generating an eccentric torque to adjust the lateral sway of the tower body in real time.

[0021] Furthermore, the first movable counterweight component and the second movable counterweight component are the two ends of the same continuous first counterweight steel cable;

[0022] The drive mechanism includes a first winch and a second winch, which are respectively located at both ends of the horizontal beam. The two ends of the first counterweight steel cable are respectively connected to the first winch and the second winch.

[0023] The first counterweight cable can be wound biased between the first winch and the second winch, so that the winding length of the first counterweight cable on the first winch side and the winding length on the second winch side form the position difference. The first counterweight cable itself serves as a counterweight for lateral balance. The first counterweight cable is made of multiple strands of scrapped lifting wire rope.

[0024] The first winch and the second winch can move synchronously on the horizontal beam to adjust their distance from the center of the tower, thereby achieving dynamic adjustment of the lever arm.

[0025] Furthermore, the first movable counterweight component and the second movable counterweight component are steel pipes with racks;

[0026] The driving mechanism includes a first motor and a second motor, which are respectively disposed at both ends of the horizontal beam. The first motor and the second motor mesh with the steel pipe on the corresponding side through gears, driving the steel pipe to move linearly on the horizontal beam to form the position difference. The steel pipe itself serves as a counterweight for lateral balance.

[0027] Furthermore, the first movable counterweight component and the second movable counterweight component can move synchronously on the horizontal beam to adjust their distance from the center of the tower body, thereby achieving dynamic adjustment of the lever arm.

[0028] When the tower crane is in operation, the control unit controls the first movable counterweight component and the second movable counterweight component to move synchronously to both ends of the horizontal beam to increase the lever arm;

[0029] When the tower crane is stopped, the control unit controls the first movable counterweight component and the second movable counterweight component to move synchronously to a position close to the center of the tower body in order to reduce the center of gravity shift.

[0030] Furthermore, the attitude monitoring unit includes one or more of a tilt sensor, a gyroscope, a mercury tilt switch, or a mechanical plumb bob device, used to monitor the tilt angle of the tower body or the horizontal angle of the working arm, and to use the angle as the actual attitude value.

[0031] A method for active dynamic balance control of a tower crane using the aforementioned system includes the following steps:

[0032] S1. Real-time monitoring steps: The attitude monitoring unit monitors the vertical state of the tower body or the horizontal state of the boom of the tower crane in real time to obtain the actual attitude value.

[0033] S2. Deviation judgment step: Compare the actual posture value with the preset standard posture value to determine whether there is a posture deviation and the direction of the deviation.

[0034] S3. Dynamic adjustment step: Based on the deviation direction, generate control commands and send them to the corresponding balancing mechanism:

[0035] If the deviation is longitudinal, control the longitudinal balancing mechanism to adjust the longitudinal balancing torque;

[0036] If the deviation is lateral, the lateral balancing mechanism is controlled to adjust the relative positions of the first movable counterweight and the second movable counterweight to form a position difference and generate a reverse eccentric torque.

[0037] S4. Closed-loop feedback step: While driving the balancing mechanism, the real-time monitoring of step S1 is continuously executed until the deviation between the actual attitude value and the standard attitude value is eliminated, forming a closed-loop control with the tower body being vertical and lateral without swaying as the direct control target.

[0038] Furthermore, in step S3, when controlling the lateral balancing mechanism, continuous, delay-free adjustment of the center of gravity is achieved by continuously adjusting the relative position difference between the first movable counterweight component and the second movable counterweight component. Specifically:

[0039] If the tower body tilts towards the first movable counterweight component, control the second movable counterweight component to move away from the tower body, so that the center of gravity shifts to the second side;

[0040] If the tower body tilts towards the second movable counterweight component, control the first movable counterweight component to move away from the tower body, so that the center of gravity shifts to the first side.

[0041] Furthermore, it also includes:

[0042] Multi-level response steps: Preset multiple sets of attitude deviation ranges with different thresholds, each corresponding to a different adjustment speed; when the actual attitude value falls into a certain deviation range, control the corresponding balancing mechanism to respond and adjust at a speed corresponding to that range;

[0043] Non-working state adjustment steps: When the tower crane is stopped and there is no load, control the longitudinal balancing mechanism and / or the lateral balancing mechanism to adjust the tower body to a state where it remains vertical and does not sway laterally.

[0044] The beneficial effects of the technical solution provided in this application are as follows:

[0045] 1. This application uses an attitude monitoring unit to monitor the vertical state of the tower or the horizontal state of the boom in real time. After comparing the actual attitude value with a preset standard attitude value, it directly generates control commands to drive the independently configured longitudinal and lateral balancing mechanisms to work together. On one hand, this invention abandons the traditional open-loop control mode based on torque calculation, adopting a closed-loop feedback control with "vertical tower and no lateral sway" as the direct control objective. It can sense and directly correct any form of dynamic inertial force disturbance, including wind load, centrifugal force during rotation, and sudden unloading, eliminating alternating bending moments on the tower, delaying metal structure fatigue, and significantly extending the service life of the tower crane equipment.

[0046] 2. This application, by setting the lateral balancing mechanism independently from the longitudinal balancing mechanism and adjusting the longitudinal balancing torque and the lateral center of gravity position separately, achieves active dynamic balancing of the tower crane in all 360° directions for the first time. It solves the technical problem that the existing technology can only solve the longitudinal sway and completely ignore the risk of lateral sway, effectively resists dynamic disturbances in any direction, and greatly improves the operational safety, wind resistance and operational accuracy of the tower crane.

[0047] 3. The balancing mechanism of the present invention is simple in design and highly adaptable. The lateral balancing mechanism provides two implementation methods: steel cable type and steel pipe gear rack type. The steel cable type is low in cost and easy to install, and is suitable for small and medium-sized tower cranes; the steel pipe type has high adjustment accuracy and good stability, and is suitable for large tower cranes. Those skilled in the art can flexibly choose according to actual working conditions. At the same time, the various embodiments can be combined to achieve a combination of flexible and rigid adjustment.

[0048] 4. This invention features a dynamic lever arm adjustment function and multi-level response logic, which can adaptively adjust the lever arm length according to different working conditions of the tower crane (working / stopping). It matches differentiated adjustment speeds according to the magnitude of posture deviation, taking into account correction capability, adjustment accuracy, and equipment stability, and achieving optimal balance control under all working conditions.

[0049] 5. The counterweight steel cable of the present invention can be made by multi-strand braiding of scrapped lifting steel wire rope, realizing the reuse of waste materials and conforming to the concept of green environmental protection; the overall structure has no complex mechanical linkage parts, making installation and maintenance convenient, reducing the equipment modification cost and later operation and maintenance cost, and has good prospects for industrial application. Attached Figure Description

[0050] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0051] Figure 1 This is a schematic diagram of the overall module structure of the system of the present invention;

[0052] Figure 2 This is a front view of the tower crane of the present invention;

[0053] Figure 3 This is a schematic diagram of the longitudinal balancing mechanism of the present invention;

[0054] Figure 4 This is a side view of the tower crane of the present invention;

[0055] Figure 5 This is a schematic diagram of the isometric projection of the tower crane of the present invention;

[0056] Figure 6 This is a schematic diagram of the first embodiment of the lateral balancing mechanism of the present invention;

[0057] Figure 7 This is a schematic diagram of the second embodiment of the lateral balancing mechanism of the present invention;

[0058] Figure 8 This is a schematic diagram of the tower crane of the present invention in the shutdown state;

[0059] Figure 9 This is a flowchart of the active dynamic balance control method of the present invention.

[0060] In the diagram: 100 Attitude monitoring unit, 101 Tilt sensor, 102 Gyroscope, 103 Mercury tilt switch, 104 Mechanical hammer device, 200 Control unit, 300 Longitudinal balancing mechanism, 301 Third winch, 302 Fourth winch, 303 Second counterweight cable, 400 Lateral balancing mechanism, 401 Horizontal beam, 402 First movable counterweight component, 403 Second movable counterweight component, 404 Drive mechanism, 405 First counterweight cable, 406 First winch, 407 Second winch, 408 Steel pipe, 409 First motor, 410 Second motor, 411 Gear, 500 Tower body, 600 Working arm, 700 Counterweight arm. Detailed Implementation

[0061] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0062] like Figure 1 , Figure 2 , Figure 5As shown, this invention provides an omnidirectional active dynamic balancing system for a tower crane. The system includes an attitude monitoring unit 100, a control unit 200, a longitudinal balancing mechanism 300, and a lateral balancing mechanism 400. The attitude monitoring unit 100 is mounted on the tower body 500 or the boom 600, preferably near the operator's cab for easy maintenance and signal transmission. It monitors the tower crane's attitude status in real time and outputs actual attitude values. The control unit 200 is electrically connected to the attitude monitoring unit 100, receives the actual attitude values, compares them with preset standard attitude values, determines whether there is an attitude deviation and its direction, and generates corresponding control commands based on the determination result. The longitudinal balancing mechanism 300 is located on the side of the boom 700 and electrically connected to the control unit 200. It adjusts the longitudinal balancing torque of the tower crane along the boom 600 direction according to the control commands. The lateral balancing mechanism 400 is independent of the longitudinal balancing mechanism 300, located at the top of the tower body, and also electrically connected to the control unit 200. It adjusts the lateral center of gravity position of the tower crane perpendicular to the boom 600 direction according to the control commands. Based on the attitude deviation direction fed back by the attitude monitoring unit 100, the control unit 200 controls the longitudinal balancing mechanism 300 and / or the lateral balancing mechanism 400 to maintain the tower body 500 in a vertical state and eliminate lateral sway. Through this structure, the present invention achieves independent or coordinated adjustment of the tower crane in both the longitudinal and lateral directions. The various units work together to form a closed-loop feedback control, capable of responding in real time to various dynamic disturbances, including wind loads, centrifugal force during rotation, and sudden unloading, thereby effectively eliminating the alternating bending moment borne by the tower body and significantly improving the safety performance and service life of the tower crane.

[0063] like Figure 1 As shown, the attitude monitoring unit 100 can be implemented using various types of sensors. For example, an inclination sensor 101 can be used to directly measure the tilt angle of the tower body 500 relative to the vertical line, or to measure the tilt angle of the working arm 600 relative to the horizontal plane. A gyroscope 102 can also be used to detect the angular velocity and integrate it to obtain the angle value. A mercury tilt switch 103 can also be used, triggering the switching of different circuits by the change in the position of a mercury bead inside a glass tube, thereby outputting a switch signal to indicate the tilt direction. Furthermore, a mechanical plumb bob device 104 is also a feasible option, determining the tilt direction through the contact between the suspended rod and the curved metal plate. In practical applications, multiple sensors can be used in combination; these sensors can be used individually or in combination to improve reliability and accuracy. The actual attitude value output in real time by the attitude monitoring unit 100 is transmitted to the control unit 200 as a feedback signal for closed-loop control.

[0064] The control unit 200 is typically implemented using a programmable logic controller (PLC), an embedded processor, or an industrial control computer. It has pre-set standard attitude values ​​(e.g., an angle of 0° corresponding to the tower's vertical position) and stores control logic programs. It incorporates multi-level deviation thresholds and corresponding adjustment speed matching logic. After receiving the actual attitude values ​​from the attitude monitoring unit 100, the control unit 200 compares and calculates to determine if a deviation exists and its direction. If a deviation exists, it generates corresponding control commands according to a pre-set control strategy and sends them to the longitudinal balancing mechanism 300 and / or the lateral balancing mechanism 400. The control unit 200 also features multi-level response speed control, allowing it to select different adjustment speeds based on the magnitude of the deviation to achieve a balance between rapid response and smooth adjustment. As the core of the entire system, the control unit directly uses the tower's attitude as the control target, eliminating the need for complex torque calculations and significantly improving control response speed and accuracy.

[0065] like Figure 3 As shown, a preferred implementation of the longitudinal balancing mechanism 300 includes a third winch 301, a fourth winch 302, and a second counterweight cable 303. The third winch 301 is located at the root of the balance arm 700 (on the side closer to the tower 500), and the fourth winch 302 is located at the tail of the balance arm 700 (on the side farther from the tower 500). The two ends of the second counterweight cable 303 are connected to the third winch 301 and the fourth winch 302, respectively, with the middle portion hanging naturally or guided by a fixed pulley. The second counterweight cable 303 can be made from multiple strands of scrapped lifting wire rope, realizing the reuse of waste materials, reducing costs, and meeting environmental protection requirements. When the control unit 200 determines that there is a longitudinal attitude deviation, it sends a control command to the third winch 301 and / or the fourth winch 302 to drive the corresponding winch to wind or unwind, causing the winding length of the second counterweight cable 303 on the winches on both sides to change. Because the second counterweight cable 303 has a certain mass, its center of gravity shifts along the length of the balance arm 700 as the winding length changes, thereby altering the balancing torque on the balance arm side and restoring the tower 500 to a vertical position. This cable design is simple in structure, and the second counterweight cable 303 can also be made from scrapped lifting wire rope, achieving the reuse of waste materials. By adjusting the winch's winding and unwinding speed, continuous and precise adjustment of the balancing torque can be achieved.

[0066] As another implementation of the longitudinal balancing mechanism, a counterweight trolley scheme can be adopted. Specifically, a guide rail can be set along the length of the counterweight arm 700, and the counterweight trolley is movably mounted on the guide rail. A winch is connected to the counterweight trolley via a wire rope, driving the counterweight trolley to move along the guide rail. By changing the position of the counterweight trolley on the counterweight arm 700, its lever arm length relative to the tower body 500 is adjusted, thereby changing the longitudinal balancing torque. This scheme can also achieve real-time adjustment of longitudinal balance, and those skilled in the art can choose a suitable method according to actual needs.

[0067] like Figure 1 , Figure 4 , Figure 5 , Figure 6 As shown, the lateral balancing mechanism 400 is the core component for achieving active lateral dynamic balancing in this invention. It includes a horizontal beam 401, a first movable counterweight component 402, a second movable counterweight component 403, and a drive mechanism 404. The horizontal beam 401 is fixedly mounted on the top of the tower body 500 and passes through the tower body axis, extending horizontally in a direction perpendicular to the tower crane's boom 600, thus forming an independent lateral balancing support structure. The first movable counterweight component 402 and the second movable counterweight component 403 are respectively disposed at both ends of the horizontal beam 401 and can move independently along the length of the horizontal beam 401. The drive mechanism 404 is electrically connected to the control unit 200 and is used to independently drive the first movable counterweight component 402 and the second movable counterweight component 403 to move. By adjusting the relative positions of the first movable counterweight component 402 and the second movable counterweight component 403, a positional difference is created, causing the center of gravity of the entire system to shift to one side, thereby generating an eccentric torque. This torque acts on the tower body 500, enabling real-time adjustment of the tower body's lateral sway. This method of generating a corrective torque using the relative positional difference of the two counterweight components avoids the inertial delay problem present in the traditional single counterweight movement, achieving rapid and precise suppression of lateral sway. Furthermore, the independent lateral balancing support structure does not affect the operation of the longitudinal balancing mechanism, ensuring the independence and coordination of adjustments in both directions.

[0068] In a preferred embodiment of the present invention, such as Figure 6As shown, the first movable counterweight component 402 and the second movable counterweight component 403 are implemented using the two ends of the same continuous first counterweight steel cable 405. At this time, the drive mechanism 404 includes a first winch 406 and a second winch 407, which are respectively located at both ends of the horizontal beam 401. The two ends of the first counterweight steel cable 405 are respectively connected to the first winch 406 and the second winch 407, with the middle portion hanging naturally or guided by pulleys. The first counterweight steel cable 405 can be made from multiple strands of scrapped lifting wire rope, realizing the reuse of waste materials, meeting environmental protection requirements, and reducing manufacturing costs. When it is necessary to adjust the lateral balance, the control unit 200 controls the first winch 406 or the second winch 407 to wind or unwind, causing the winding length of the first counterweight steel cable 405 on the two winches to change, forming a length difference. Since the first counterweight steel cable 405 itself has a certain mass, its center of gravity will move with the change in length difference, thereby generating an eccentric torque. This steel cable scheme is simple in structure and low in cost. Furthermore, the first counterweight steel cable 405 can be made from multiple strands of scrapped lifting wire rope, achieving the reuse of waste materials and meeting environmental protection requirements. Simultaneously, the first winch 406 and the second winch 407 can be configured to move synchronously on the horizontal beam 401 to adjust their distance from the center of the tower 500, thereby changing the lever arm length and further enhancing the adjustment capability. Specifically, as... Figure 8 As shown, before the tower crane starts working, the two winches can be moved synchronously to both ends of the crossbeam to increase the lever arm; before stopping, they can be moved synchronously to the center of the tower body to avoid unnecessary shaking when not in operation.

[0069] In another preferred embodiment of the invention, such as Figure 7 As shown, the first movable counterweight component 402 and the second movable counterweight component 403 are implemented using steel pipes 408 with racks. The drive mechanism 404 includes a first motor 409 and a second motor 410, respectively located at both ends of the horizontal beam 401. Gears are mounted on the output shafts of the first motor 409 and the second motor 410, and these gears mesh with the racks on the corresponding steel pipes 408. When the control unit 200 issues a control command, the first motor 409 and / or the second motor 410 rotate, driving the steel pipes 408 to move linearly on the horizontal beam 401 via rack and pinion transmission, thereby changing the positions of the steel pipes 408 on both sides and creating a positional difference. The steel pipe 408 itself, as a counterweight, has a large mass and moves smoothly, making it particularly suitable for large tower cranes with higher requirements for control precision and stability. This scheme offers higher adjustment precision, stronger anti-disturbance capability, and is suitable for the complex operating conditions of large tower cranes. Similarly, the motor and gear mechanism can also be designed to be movable to achieve dynamic adjustment of the lever arm.

[0070] To further enhance the adaptability of the lateral balancing mechanism, this invention also includes a dynamic lever arm adjustment function. For example...Figure 1 , Figure 8 As shown, the first movable counterweight component 402 and the second movable counterweight component 403 (whether the first counterweight cable 405 or the steel pipe 408 option) can move synchronously on the horizontal beam 401 to adjust their distance from the center of the tower body 500. Specifically, when the tower crane is in operation, the control unit 200 controls the first movable counterweight component 402 and the second movable counterweight component 403 to move synchronously to both ends of the horizontal beam 401, thereby increasing the lever arm and allowing a smaller center of gravity offset to generate a larger eccentric moment, enhancing the correction capability. When the tower crane is stopped, the control unit 200 controls them to move synchronously to a position close to the center of the tower body 500, so that the center of gravity is as close as possible to the tower body axis, reducing unnecessary swaying caused by wind load and other factors when the crane is stopped. This dynamic adjustment function of the lever arm further optimizes the overall performance of the system. This dynamic adjustment function of the lever arm realizes the adaptive matching between the tower crane's operating conditions and the balancing mechanism, further optimizing the overall performance of the system and improving the stability of the equipment under different operating conditions.

[0071] The attitude monitoring unit 100 can be implemented in various ways, such as Figure 1 As shown, in addition to the aforementioned tilt sensor 101, gyroscope 102, mercury tilt switch 103, and mechanical hammer device 104, other sensors capable of sensing angle or tilt can also be used. These sensors can be installed at the top, middle, or bottom of the tower 500, or at the end of the boom 600, as long as they can accurately reflect the vertical state of the tower or the horizontal state of the boom. In practical applications, sensors are usually installed near the operator's cab for easy maintenance and signal transmission. The sensor output signal can be analog, digital, or switching, and the control unit 200 processes it accordingly based on the signal type. The combined use of multiple sensors can effectively improve monitoring reliability, avoid monitoring failure caused by a single sensor malfunction, and ensure the safe operation of the system.

[0072] The following is combined with Figure 9 The active dynamic balancing control method for tower cranes provided by this invention is described in detail. This method, implemented using the aforementioned system, includes the following steps:

[0073] S1. Real-time Monitoring Steps: The attitude monitoring unit 100 monitors the vertical state of the tower crane's tower body 500 or the horizontal state of the boom 600 in real time to obtain the actual attitude value. The attitude monitoring unit 100 continuously collects data and sends the actual attitude value to the control unit 200 in real time. For example, when using the tilt sensor 101, the actual attitude value is the specific tilt angle value; when using the mercury tilt switch 103, the actual attitude value is the switch signal indicating the tilt direction. High-frequency continuous acquisition ensures that the system can promptly capture changes in the tower's attitude, laying the foundation for subsequent real-time adjustments.

[0074] S2. Deviation Judgment Step: The control unit 200 compares the received actual posture value with the preset standard posture value to determine whether a posture deviation exists and its direction. The standard posture value is usually set to the value corresponding to the verticality of the tower body or the horizontality of the working arm (e.g., 0°). If the difference between the actual posture value and the standard posture value exceeds the preset allowable error range, a deviation is determined, and the direction of the deviation is determined based on the sign of the difference (e.g., tilting towards the working arm or the counterweight arm, or tilting towards the first counterweight component or the second counterweight component). To improve the precision of the adjustment, this step can also preset multiple sets of posture deviation ranges with different thresholds, each corresponding to a different adjustment speed. For example, slow adjustment is used when the deviation is small to avoid over-adjustment; medium-speed adjustment is used when the deviation is moderate; and fast adjustment is used when the deviation is large to quickly restore balance. The preset allowable error range and multi-level deviation thresholds make the system's deviation judgment more accurate, providing a reliable basis for differentiated adjustment.

[0075] S3. Dynamic Adjustment Step: Based on the deviation direction obtained in the deviation judgment step, the control unit 200 generates corresponding control commands and sends them to the corresponding balancing mechanism. Specifically:

[0076] If the deviation is longitudinal (i.e., the tower leans towards the working arm or counterweight arm), the control unit 200 sends a control command to the longitudinal balancing mechanism 300 to drive the third winch 301 and / or the fourth winch 302 to wind / unwind, changing the center of gravity position of the second counterweight cable 303 and altering the longitudinal balancing torque until the tower returns to vertical. During the adjustment process, the control unit 200 determines the direction and speed of movement of the counterweight trolley 301 based on the magnitude and direction of the deviation and continuously monitors changes in the actual attitude values.

[0077] If the deviation is lateral (i.e., the tower body tilts towards the first movable counterweight component 402 or the second movable counterweight component 403), the control unit 200 sends a control command to the lateral balancing mechanism 400 to drive the first movable counterweight component 402 and the second movable counterweight component 403 to move, adjusting their relative positions to create a positional difference and generate a reverse eccentric torque. Specifically, if the tower body tilts towards the first movable counterweight component 402, the second movable counterweight component 403 is controlled to move away from the tower body, shifting the center of gravity to the second side and generating a reverse torque to straighten the tower body; conversely, if it tilts towards the second side, the first movable counterweight component 402 is controlled to move away from the tower body. This lateral adjustment has no step-by-step movement delay, enabling real-time tracking and correction of tower body sway, effectively suppressing lateral sway caused by dynamic disturbances. This adjustment method achieves continuous, delay-free adjustment of the center of gravity, enabling real-time tracking of tower body sway changes.

[0078] S4. Closed-loop feedback step: While driving the balancing mechanism, the control unit 200 continuously executes the real-time monitoring of step S1, obtains the updated actual attitude value, and compares it with the standard attitude value to determine whether the deviation has been eliminated. If the deviation has not been eliminated, adjustment continues; if the deviation has been eliminated, the corresponding balancing mechanism stops its operation to maintain the system in a balanced state. This cycle is repeated to form a closed-loop control with the tower's verticality and lateral stability as the direct control target. Closed-loop feedback control is one of the core innovations of this invention. It directly uses the tower's attitude as the control target, abandoning traditional torque calculation and open-loop control, realizing real-time perception and immediate correction of dynamic disturbances, and completely eliminating the alternating bending moment of the tower.

[0079] To ensure the continuity and real-time nature of the adjustment during lateral adjustment, this invention further specifies a continuous, delay-free adjustment method. As described in step S3, when a lateral deviation is detected, the control unit 200 does not use step-by-step movement, but instead continuously controls the drive mechanism 404 to continuously change the relative position difference between the first movable counterweight component 402 and the second movable counterweight component 403 until the tower body returns to vertical. This continuous adjustment method avoids the delay and impact caused by traditional mechanical positioning devices, enabling the system to respond to the dynamic swaying of the tower crane in real time, and is particularly suitable for lateral balance during continuous slewing operations of the tower crane.

[0080] Furthermore, the method of the present invention also includes a multi-level response step and a non-working state adjustment step. In the multi-level response step, the control unit 200 internally presets multiple deviation threshold ranges, each range corresponding to an adjustment speed level. When the actual attitude value falls into a certain deviation range, the control unit 200 drives the balancing mechanism to operate at the speed corresponding to that range, thereby achieving differentiated responses under different deviation conditions. This ensures smooth fine-tuning under small deviations and rapid correction under large deviations. The multi-level response logic effectively avoids over-adjustment under small deviations and adjustment lag under large deviations, balancing the stability and speed of the system. In the non-working state adjustment step, when the tower crane is stopped and there is no load, the control unit 200 controls the longitudinal balancing mechanism 300 and / or the lateral balancing mechanism 400 to adjust to a state where the tower body remains vertical and laterally stable. For example, for the lateral balancing mechanism 400, the first movable counterweight component 402 and the second movable counterweight component 403 can be controlled to move synchronously to a position close to the center of the tower body, reducing the lever arm and avoiding unnecessary swaying and stress on the tower body due to the fixed counterweight in windy weather. Automatic adjustments during non-operating periods further enhance the equipment's intelligence, reduce manual operation, and decrease equipment wear and safety hazards. These additional steps further improve the system's intelligence and security.

[0081] It should be noted that the above embodiments can be implemented individually or in combination as needed. For example, the steel cable scheme can be combined with the counterweight trolley scheme to form a system with both flexible and rigid adjustment characteristics. Alternatively, multi-level response can be combined with non-working state adjustment to achieve optimal control under all operating conditions. Small tower cranes can preferentially adopt a lightweight scheme of steel cable longitudinal + steel cable lateral, while large tower cranes can adopt a high-precision scheme of steel cable longitudinal + steel pipe lateral. Those skilled in the art can make reasonable selections and modifications according to the actual needs of the tower crane's tonnage, operating conditions, etc., and all of these should be covered within the protection scope of this invention.

Claims

1. A tower crane omnidirectional active dynamic balancing system, characterized in that, include: The attitude monitoring unit (100) is installed on the tower body (500) or the boom (600) to monitor the attitude status of the tower crane in real time and output the actual attitude value. The control unit (200) is electrically connected to the attitude monitoring unit (100) and is used to receive the actual attitude value, compare it with the preset standard attitude value, determine the attitude deviation and the direction of the deviation, and generate control commands. A longitudinal balancing mechanism (300) is provided on the side of the balance arm (700) and electrically connected to the control unit (200) for adjusting the longitudinal balancing torque of the tower crane along the working arm (600) according to the control command. A lateral balancing mechanism (400) is set independently of the longitudinal balancing mechanism (300) and is electrically connected to the control unit (200) for adjusting the lateral center of gravity position of the tower crane in the direction perpendicular to the boom (600) according to the control command. The control unit (200) controls the longitudinal balancing mechanism (300) and / or the lateral balancing mechanism (400) to operate according to the attitude deviation direction fed back by the attitude monitoring unit (100), so that the tower body (500) remains vertical and the lateral sway is eliminated.

2. The active dynamic balancing system according to claim 1, characterized in that, The longitudinal balancing mechanism (300) includes: The third winch (301) and the fourth winch (302) are respectively located at the root and tail of the counterweight arm (700); The second counterweight cable (303) is connected at both ends to the third winch (301) and the fourth winch (302) respectively. The second counterweight cable (303) can be wound in a biased manner between the third winch (301) and the fourth winch (302). The longitudinal balance torque is changed by altering the winding length distribution of the second counterweight cable (303) on the third winch (301) and the fourth winch (302). The center of gravity of the second counterweight cable (303) is moved along the length of the balance arm (700). The second counterweight cable (303) is made of multiple strands of scrapped lifting wire rope.

3. The active dynamic balancing system according to claim 1, characterized in that, The lateral balancing mechanism (400) includes: A horizontal beam (401) is fixedly installed on the top of the tower body (500) and passes through the tower body axis. It extends horizontally in a direction perpendicular to the tower crane boom (600) to form an independent transverse balance support structure. The first movable counterweight component (402) and the second movable counterweight component (403) are respectively disposed at both ends of the horizontal beam (401) and can move independently along the length direction of the horizontal beam (401). The drive mechanism (404) is electrically connected to the control unit (200) and is used to independently drive the first movable counterweight component (402) and the second movable counterweight component (403) to move. In this process, by adjusting the relative positions of the first movable counterweight component (402) and the second movable counterweight component (403), a positional difference is formed, causing the center of gravity of the system to shift to one side, generating an eccentric torque to adjust the lateral sway of the tower body (500) in real time.

4. The active dynamic balancing system according to claim 3, characterized in that, The first movable counterweight component (402) and the second movable counterweight component (403) are the two ends of the same continuous first counterweight steel cable (405); The drive mechanism (404) includes a first winch (406) and a second winch (407), which are respectively disposed at both ends of the horizontal beam (401). The two ends of the first counterweight steel cable (405) are respectively connected to the first winch (406) and the second winch (407). The first counterweight cable (405) can be wound biased between the first winch (406) and the second winch (407), so that the winding length of the first counterweight cable (405) on the side of the first winch (406) and the winding length on the side of the second winch (407) form the position difference. The first counterweight cable (405) itself serves as a counterweight for lateral balance. The first counterweight cable (405) is made of multiple strands of scrapped lifting wire rope. The first winch (406) and the second winch (407) can move synchronously on the horizontal beam (401) to adjust their distance from the center of the tower body (500) and realize dynamic adjustment of the lever arm.

5. The active dynamic balancing system according to claim 3, characterized in that, The first movable counterweight component (402) and the second movable counterweight component (403) are steel pipes (408) with racks. The drive mechanism (404) includes a first motor (409) and a second motor (410), which are respectively disposed at both ends of the horizontal beam (401). The first motor (409) and the second motor (410) mesh with the steel pipe (408) on the corresponding side through gears, driving the steel pipe (408) to move linearly on the horizontal beam (401) to form the position difference. The steel pipe (408) itself serves as a counterweight for lateral balance.

6. The active dynamic balancing system according to claim 3, characterized in that, The first movable counterweight component (402) and the second movable counterweight component (403) can move synchronously on the horizontal beam (401) to adjust their distance from the center of the tower body (500), thereby achieving dynamic adjustment of the lever arm. When the tower crane is in operation, the control unit (200) controls the first movable counterweight component (402) and the second movable counterweight component (403) to move synchronously to both ends of the horizontal beam (401) to increase the lever arm; When the tower crane is stopped, the control unit (200) controls the first movable counterweight component (402) and the second movable counterweight component (403) to move synchronously to a position close to the center of the tower body (500) in order to reduce the center of gravity shift.

7. The active dynamic balancing system according to claim 1, characterized in that, The attitude monitoring unit (100) includes one or more of the following: tilt sensor (101), gyroscope (102), mercury tilt switch (103) or mechanical hammer device (104), used to monitor the tilt angle of the tower body (500) or the horizontal angle of the working arm (600), and use the angle as the actual attitude value.

8. A method for active dynamic balance control of a tower crane using the system described in any one of claims 1-7, characterized in that, Includes the following steps: S1. Real-time monitoring steps: The attitude monitoring unit (100) monitors the vertical state of the tower body (500) or the horizontal state of the boom (600) of the tower crane in real time to obtain the actual attitude value. S2. Deviation Judgment Step: Compare the actual posture value with the preset standard posture value to determine whether there is a posture deviation and the direction of the deviation. S3. Dynamic adjustment step: Based on the deviation direction, generate control commands and send them to the corresponding balancing mechanism: If the deviation is longitudinal, control the longitudinal balancing mechanism (300) to adjust the longitudinal balancing torque; If the deviation is lateral, the lateral balancing mechanism (400) is controlled to adjust the relative position of the first movable counterweight (402) and the second movable counterweight (403) to form a position difference and generate a reverse eccentric torque; S4. Closed-loop feedback step: While driving the balancing mechanism to move, the real-time monitoring of step S1 is continuously executed until the deviation between the actual attitude value and the standard attitude value is eliminated, forming a closed-loop control with the tower body (500) being vertical and without lateral sway as the direct control target.

9. The control method according to claim 8, characterized in that, In step S3, when controlling the lateral balancing mechanism (400) to operate, the center of gravity is continuously adjusted without delay by continuously adjusting the relative position difference between the first movable counterweight component (402) and the second movable counterweight component (403). Specifically: If the tower body (500) tilts toward the first movable counterweight component (402), control the second movable counterweight component (403) to move away from the tower body (500), so that the center of gravity shifts to the second side; If the tower body (500) tilts toward the second movable counterweight component (403), control the first movable counterweight component (402) to move away from the tower body (500) so that the center of gravity shifts toward the first side.

10. The control method according to claim 8, characterized in that, Also includes: Multi-level response steps: Preset multiple sets of attitude deviation ranges with different thresholds, each corresponding to a different adjustment speed; When the actual attitude value falls within a certain deviation range, the corresponding balancing mechanism is controlled to respond and adjust at a speed corresponding to that range. Non-working state adjustment steps: When the tower crane is stopped and there is no load, control the longitudinal balancing mechanism (300) and / or the lateral balancing mechanism (400) to adjust the tower body (500) to a state where it is vertical and there is no lateral sway.

Images