Automatic hooking system of gantry crane

Abstract

The invention provides an automatic hooking system of a gantry crane, which relates to the technical field of industrial automatic control, and comprises a gantry crane, a cinder ladle, a hook device and a PLC (Programmable Logic Controller) control system, lifting lugs are arranged on two sides of the cinder ladle; a movable bottom hook is hinged to the bottom; in the lifting hook device, a main hook lifting appliance is hooked with a lifting lug, an auxiliary hook lifting appliance is hooked with a movable bottom hook, a visual acquisition unit acquires hooking images, and the main hook lifting appliance and the auxiliary hook lifting appliance are both double-lifting-point lifting appliances; a PLC in the PLC control system is connected with a positioning module, a traveling mechanism and a hoisting mechanism, and the positioning module positions the traveling mechanism and the hoisting mechanism. According to the system, the stability of the hooking process is improved by adopting a double-lifting-point lifting appliance structure; the movable bottom hook is convenient for the auxiliary hook lifting appliance to be automatically hung to finish hooking connection; the visual acquisition unit ensures that the hooking process is accurately completed; a positioning module is introduced to enable the system to form closed-loop control, high-precision position feedback and control are achieved, automatic hooking is further achieved, and potential safety hazards possibly existing when field personnel participate are reduced.

Description

Technical Field

[0001] This invention relates to the field of industrial automatic control technology, and in particular to an automatic hooking system for gantry cranes. Background Art

[0002] The slag cooling field in metal smelting enterprises is mainly used to treat the high-temperature slag generated during the smelting process. Specifically, it uses natural cooling or water cooling to slowly cool the high-temperature slag to a safe temperature for subsequent processing, thereby recovering valuable metal resources, reducing waste and improving resource utilization.

[0003] Currently, metal smelting enterprises mainly transport slag ladles using gantry cranes or wheeled slag ladle cars. Regardless of the mode of transport, manual intervention is involved. In particular, the lifting, hooking, and dumping of slag ladles by gantry cranes require coordination between dispatchers and crane drivers using walkie-talkies. The scheduling between gantry cranes also relies mainly on manual visual inspection and walkie-talkie communication. Traditional slag ladle temperature measurement is also manually operated by people holding temperature guns. The entire process has a low level of automation, always requires manual contact with the slag ladle, has low safety, and poses a significant operational risk. Summary of the Invention

[0004] To address the shortcomings of the existing technology, this invention provides an automatic hooking system for gantry cranes, which solves the technical problems of low intelligence and poor safety caused by the need for manual assistance in the lifting and dumping of slag bags using gantry cranes in the existing technology.

[0005] This invention provides an automatic hooking system for a gantry crane, comprising a gantry crane, a slag bag, a hook device, and a PLC control system. The slag bag has lifting lugs on both sides and a movable bottom hook hinged to its bottom. The gantry crane includes a traveling mechanism and a hoisting mechanism. The hook device is connected to the traveling mechanism via the hoisting mechanism. The traveling mechanism drives the hook device to move above the slag bag, and the hoisting mechanism drives the hook device to move vertically along the slag bag. The hook device includes a vision acquisition unit, a main hook lifting device, and a secondary hook lifting device. The main hook lifting device hooks onto the lifting lugs, and the secondary hook lifting device hooks onto the movable bottom hook. The vision acquisition unit acquires images of the hook connection between the main hook lifting device and the lifting lugs. Both the main hook lifting device and the secondary hook lifting device are dual-point lifting devices. The PLC control system includes a PLC controller and a positioning module. The PLC controller is connected to the positioning module, the traveling mechanism, and the hoisting mechanism, respectively. The positioning module is used to position the traveling mechanism and the hoisting mechanism.

[0006] Optionally, the traveling mechanism includes a main trolley and an auxiliary trolley. The main trolley is mounted on the main beam of the gantry crane, and the auxiliary trolley is mounted on the secondary beam of the gantry crane. The main hook lifting device includes a main hook corresponding to the lifting lug. The main hook is drivenly connected to the hoisting mechanism and is used to hook onto the lifting lug. The auxiliary hook lifting device includes a balance beam and an auxiliary hook. The balance beam is connected to the hoisting mechanism. Both ends of the balance beam are provided with movable pulley blocks. A horizontal tilt sensor is provided on the balance beam. The auxiliary hook includes a flexible lifting device and a V-shaped steel bar connected together. One end of the flexible lifting device is flexibly driven connected to the movable pulley block, and the other end of the flexible lifting device is connected to the V-shaped steel bar. The V-shaped steel bar is used to hook onto the movable bottom hook. The opening direction of the main hook is opposite to that of the auxiliary hook.

[0007] Optionally, the visual acquisition unit includes multiple 3D detection cameras; the 3D detection cameras are positioned on the main trolley near the main hook, and the 3D detection cameras are aimed at the connection point between the main hook and the lifting lug, for acquiring the connection image of the main hook and the lifting lug.

[0008] Optionally, the movable bottom hook includes a fixed connecting section and a movable connecting section; the first end of the fixed connecting section is fixedly connected to the bottom of the slag bag; the first end of the movable connecting section is hinged to the second end of the fixed connecting section, and the second end of the movable connecting section is used to hook with the auxiliary hook lifting device.

[0009] Optionally, the positioning module includes a trolley positioning unit and a hoisting positioning unit; the trolley positioning unit includes a Gray bus, an electromagnetic matching device, and a position detection sensor. The Gray bus is installed on the trolley track where the trolley mechanism is located, and the electromagnetic matching device is installed on the trolley mechanism. The Gray bus and the electromagnetic matching device maintain a non-contact relative motion state to obtain the position information of the trolley mechanism. The position detection sensor is set on the trolley mechanism and is connected to the PLC controller via Profinet bus communication. The hoisting mechanism includes a hoisting drum. The main hook and the auxiliary hook are respectively connected to the trolley mechanism through the hoisting drum. The hoisting positioning unit includes an absolute rotary encoder, a dual-contact limit switch, a proximity switch, and a calibration angle iron. The absolute rotary encoder is coaxially mounted with the hoisting drum. The dual-contact limit switch is set on the hoisting drum, and the proximity switch and the calibration angle iron are set on the side of the hoisting drum.

[0010] Optionally, the PLC control system further includes a safety protection module; the safety protection module includes mechanical limit switches, proximity switches, and radar ranging devices. The mechanical limit switches are located at both ends of the traveling track where the traveling mechanism is located. The proximity switches are located on the traveling track and maintain a preset distance from the mechanical limit switches. The radar ranging devices are located on both sides of the traveling mechanism. The proximity switches and the radar ranging devices are respectively connected to the PLC controller.

[0011] Optionally, the gantry crane automatic hooking system further includes a position recognition system; the position recognition system includes an infrared thermal imager, which is installed below the main beam of the gantry crane for positioning the slag bag.

[0012] Optionally, the position recognition system further includes a laser rangefinder and a stop structure; the stop structure is set on the transport track where the slag bag is located, and is used to stop the slag bag at the initial hoisting position; the laser rangefinder is set on one side of the initial hoisting position, and the laser rangefinder is connected to the PLC controller.

[0013] Optionally, the PLC control system further includes a crane anti-sway module; the crane anti-sway module includes an anti-sway controller, a frequency converter, and a braking resistor. The anti-sway controller and the frequency converter are respectively connected to the PLC controller. The frequency converter is connected to the variable frequency motor of the crane mechanism and the variable frequency motor of the hoisting mechanism based on Profinet bus communication. The braking resistor is connected in parallel with the DC bus of the frequency converter. The anti-sway controller is used to calculate the target data curve based on the working status information of the hook device and send the target speed curve to the PLC controller, so that the PLC controller controls the frequency converter and the braking resistor to work, thereby adjusting the running speed of the crane mechanism and the hoisting mechanism.

[0014] Optionally, the gantry crane automatic hooking system further includes a remote control system; the remote control system includes a central control room control system, a driver's cab control system, and an auxiliary system. The central control room control system and the driver's cab control system are respectively connected to the PLC control system. The central control room control system is used to execute a fully automatic control mode or a remote manual control mode for the gantry crane. The driver's cab control system is installed on the gantry crane and is used to execute a manual operation mode for the gantry crane. The auxiliary system is used to ensure the stable operation of the remote control system.

[0015] The automatic hooking system for gantry cranes provided by this invention adopts a dual-point lifting structure for the main and auxiliary hooks, significantly improving the stability and anti-eccentric load capacity of the hook device during the connection process with the slag bag, enhancing the force balance, and reducing the risk of disengagement. The movable bottom hook hinged at the bottom of the slag bag can swing freely within a certain range, facilitating the automatic hooking of the auxiliary hook and improving the success rate of automatic hooking, meeting the hooking requirements of the slag bag in various postures. The visual acquisition unit in the hook device can acquire the hooking image of the main hook to ensure accurate completion of the hooking process. A positioning module is introduced, forming a closed-loop control with the PLC controller, gantry mechanism, and hoisting mechanism, realizing high-precision position feedback and control, ensuring that the hook device can accurately reach the target position, thereby achieving automatic hooking. The PLC controller dynamically adjusts the gantry and hoisting actions in conjunction with the positioning signal, always maintaining high repeatability positioning accuracy, making the entire hooking process more precise and controllable. Furthermore, the precise positioning capability allows the system to complete the entire process from positioning to hooking without human intervention, reducing the potential safety hazards of on-site personnel involvement.

[0016] Other features and advantages of the invention will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the written description, claims, and drawings.

[0017] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0018] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0019] Figure 1 A schematic diagram of the overall structure of the automatic hook system for a gantry crane in one embodiment provided in this application;

[0020] Figure 2 A schematic diagram of the connection between the hook device and the slag bag in an automatic hook system of a gantry crane provided in this application;

[0021] Figure 3 A three-dimensional structural diagram of the hook connection between the hook device and the slag bag in an automatic hook system of a gantry crane provided in this application;

[0022] Figure 4 A schematic diagram of the connection structure of the 3D detection camera in the automatic hook system of a gantry crane provided in one embodiment of this application;

[0023] Figure 5 A schematic diagram of the position recognition system in the automatic hook system of a gantry crane provided in one embodiment of this application;

[0024] Figure 6 A system architecture diagram of the PLC control system in an automatic hook system of a gantry crane provided in this application.

[0025] In the picture:

[0026] 1. Slag bag; 2. Lifting lug; 3. Movable bottom hook; 301. Fixed connecting section; 302. Movable connecting section; 4. Main hook; 5. Balance beam; 6. Auxiliary hook; 601. Flexible lifting device; 602. V-shaped steel bar; 7. 3D inspection camera. Detailed Implementation

[0027] The present application will be described in detail below with reference to the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features described in the embodiments of the present application can be combined with each other.

[0028] In one embodiment, such as Figure 1 As shown, an automatic hooking system for a gantry crane is provided, including a gantry crane, a slag bag 1, a hook device, and a PLC control system. Lifting lugs 2 are provided on both sides of the slag bag 1, and a movable bottom hook 3 is hinged to the bottom of the slag bag 1. The gantry crane includes a traveling mechanism and a hoisting mechanism. The hook device is connected to the traveling mechanism through the hoisting mechanism. The traveling mechanism is used to move the hook device above the slag bag 1, and the hoisting mechanism is used to move the hook device vertically along the slag bag 1. The hook device includes a vision acquisition unit, a main hook lifting device, and an auxiliary hook lifting device. The main hook lifting device is used to hook onto the lifting lugs 2, and the auxiliary hook lifting device is used to hook onto the movable bottom hook 3. The vision acquisition unit is used to acquire images of the hook connection between the main hook lifting device and the lifting lugs 2. Both the main hook lifting device and the auxiliary hook lifting device are double-point lifting devices. The PLC control system includes a PLC controller and a positioning module. The PLC controller is connected to the positioning module, the traveling mechanism, and the hoisting mechanism respectively. The positioning module is used to position the traveling mechanism and the hoisting mechanism.

[0029] The automatic hooking system for gantry cranes provided in this embodiment adopts a dual-point lifting structure for the main and auxiliary hooks, which significantly improves the stability and anti-eccentric load capacity of the hook device during the connection process with the slag bag 1, enhances the force balance, and reduces the risk of disengagement. The movable bottom hook 3, hinged at the bottom of the slag bag 1, can swing freely within a certain range, facilitating the automatic hooking of the auxiliary hook and improving the success rate of automatic hooking, meeting the hooking requirements of the slag bag 1 in various postures. The visual acquisition unit in the hook device can acquire the hooking image of the main hook to ensure accurate completion of the hooking process. A positioning module is introduced, forming a closed-loop control with the PLC controller, gantry mechanism, and hoisting mechanism, realizing high-precision position feedback and control, ensuring that the hook device can accurately reach the target position, thereby achieving automatic hooking. The PLC controller dynamically adjusts the gantry and hoisting actions in combination with the positioning signal, always maintaining high repeatability positioning accuracy, making the entire hooking process more precise and controllable. Furthermore, the precise positioning capability allows the system to complete the entire process from positioning to hooking without human intervention, reducing the potential safety hazards of on-site personnel involvement.

[0030] In one embodiment, the gantry crane mechanism includes a main trolley and an auxiliary trolley. The main trolley is mounted on the main beam of the gantry crane, and the auxiliary trolley is mounted on the secondary beam of the gantry crane. The main hook lifting device includes a main hook 4 corresponding to the lifting lug 2. The main hook 4 is drivenly connected to the hoisting mechanism and is used to hook onto the lifting lug 2. The auxiliary hook lifting device includes a balance beam 5 and an auxiliary hook 6. The balance beam 5 is connected to the hoisting mechanism. Both ends of the balance beam 5 are provided with movable pulley blocks. A horizontal tilt sensor is provided on the balance beam 5. The auxiliary hook 6 includes a flexible lifting device 601 and a V-shaped steel bar 602 connected to each other. One end of the flexible lifting device 601 is flexibly driven connected to the movable pulley block, and the other end of the flexible lifting device 601 is connected to the V-shaped steel bar 602. The V-shaped steel bar 602 is used to hook onto the movable bottom hook 3. The opening direction of the main hook 4 is opposite to that of the auxiliary hook 6.

[0031] The traditional auxiliary hook structure includes a fixed pulley and an iron chain plus an iron hook fixed on the gantry trolley. It uses a single-axis pulley for release. When the auxiliary hook is near the ground, it is manually hooked. During this process, the safety of the operator cannot be effectively guaranteed.

[0032] In this embodiment, as Figure 2 and Figure 3As shown, the rope-releasing structure of the auxiliary hook 6 is first changed to a structure with a double moving pulley block and a balance beam 5. Specifically, the moving pulley block is placed at both ends of the balance beam 5, and a double lifting point structure is adopted to improve the stability of the auxiliary hook 6. The upper part of the auxiliary hook 6 adopts a special flexible lifting tool 601, and the lower part adopts a V-shaped steel bar 602. At the same time, a horizontal tilt sensor is added to the balance beam 5 to ensure that the system can monitor the state of the balance beam 5. Finally, in order to improve the safety of automatic bag hanging, a weighing sensor is also configured on the auxiliary trolley to determine whether the auxiliary hook 6 reliably hooks onto or detaches from the movable bottom hook 3 of the slag bag 1.

[0033] Furthermore, the visual acquisition unit includes multiple 3D detection cameras 7; the 3D detection cameras 7 are set on the main trolley close to the main hook 4, and the 3D detection cameras 7 are aimed at the hooking point between the main hook 4 and the lifting lug 2, for acquiring the hooking image between the main hook 4 and the lifting lug 2.

[0034] In this embodiment, 3D detection cameras 7 are also installed on both sides of the main hook 4, specifically as follows: Figure 4 As shown, multiple 3D inspection cameras 7 can work collaboratively. Each 3D inspection camera 7 is powered by 220V, uses aviation plug wiring, has millimeter-level inspection accuracy, operates at temperatures from -10 to 70℃, and has an IP54 protection rating. After hooking, the 3D inspection camera 7 takes pictures of the two main hooks 4, obtaining images of the hook connection between the main hooks 4 and the lifting lugs 2. The 3D inspection camera 7 is connected to a PLC controller, sending the acquired hook connection images to a host computer. An image recognition algorithm is then used to calculate whether the main hooks 4 and lifting lugs 2 are correctly aligned without offset, assisting in verifying the hook's position. When it is detected that the hook reliably hooks the lifting lugs 2, the PLC controller sends a command to the gantry crane to place the slag bag 1 in a slow cooling area for slow cooling. Conversely, if it is detected that the hook does not reliably hook the lifting lugs 2, the PLC controller sends a command to the gantry crane to re-hook the lugs. This cycle continues until the gantry crane can reliably lift the slag bag 1.

[0035] In one embodiment, such as Figure 3 As shown, the movable bottom hook 3 includes a fixed connecting section 301 and a movable connecting section 302; the first end of the fixed connecting section 301 is fixedly connected to the bottom of the slag bag 1; the first end of the movable connecting section 302 is hinged to the second end of the fixed connecting section 301, and the second end of the movable connecting section 302 is used to hook with the auxiliary hook lifting device.

[0036] Specifically, the fixed connecting section 301, serving as the basic frame of the movable bottom hook 3, can be made of high-strength steel to ensure sufficient strength and durability under high temperature and heavy load conditions. It is firmly connected to the bottom of the slag bag 1 through precision-machined pins and bolts, ensuring the stability and reliability of the structure. The movable connecting section 302 is hinged to the fixed connecting section 301 through a hinge mechanism, allowing the movable connecting section 302 to rotate and swing within a certain range. The second end of the movable connecting section 302 is hook-shaped and used to hook with the auxiliary hook lifting device, improving the flexibility of hooking and unhooking. It can also adapt to auxiliary hook lifting devices at different angles and positions. Considering that the auxiliary hook 6 is equipped with a V-shaped steel bar 602 at the bottom, it is easy to automatically align with the movable bottom hook 3 to achieve fast and reliable hooking operation. At the same time, when unhooking is required, the V-shaped steel bar 602 can be easily withdrawn to avoid jamming.

[0037] In this embodiment, the movable bottom hook 3 combines the stability of the fixed connecting section 301 with the flexibility of the movable connecting section 302, realizing the automated hooking and unhooking of the slag bag 1. While ensuring the stability of the hooking process, it reduces the need for manual intervention and improves work efficiency.

[0038] In one embodiment, the positioning module includes a trolley positioning unit and a hoisting positioning unit. The trolley positioning unit includes a Gray bus, an electromagnetic matching device, and a position detection sensor. The Gray bus is installed on the trolley track where the trolley mechanism is located, and the electromagnetic matching device is installed on the trolley mechanism. The Gray bus and the electromagnetic matching device maintain a non-contact relative motion state to obtain the position information of the trolley mechanism. The position detection sensor is installed on the trolley mechanism and is connected to the PLC controller via Profinet bus communication. The hoisting mechanism includes a hoisting drum. The main hook and the auxiliary hook are respectively connected to the trolley mechanism through the hoisting drum. The hoisting positioning unit includes an absolute rotary encoder, a double-contact limit switch, a proximity switch, and a calibration angle iron. The absolute rotary encoder is coaxially mounted with the hoisting drum. The double-contact limit switch is installed on the hoisting drum, and the proximity switch and the calibration angle iron are installed on the side of the hoisting drum.

[0039] In this embodiment, on the one hand, the trolley positioning unit in the positioning module is used to position the trolley mechanism. Specifically, considering that hooking operations and transshipment / unloading operations are low-fault-tolerance, high-precision operations, a Gray busbar with high absolute positioning accuracy, low communication delay, and strong resistance to environmental interference is used for feedback of the absolute position of the trolley mechanism. The trolley positioning unit specifically includes a ground electrical cabinet, a vehicle-mounted electrical cabinet, a Gray busbar, and an electromagnetic matching device, etc. The ground electrical cabinet includes a data interpreter, etc., and the vehicle-mounted electrical cabinet includes an electromagnetic generator, etc. The Gray busbar is composed of a flat rubber synthetic outer shell and an internal core wire braided according to the binary digital encoding rule. It can be installed in the horizontal direction of the trolley mechanism's operation or on the fence next to the track. For example, when positioning the main trolley, the Gray busbar is installed on one side of the ground parallel to the power supply line, along the main trolley's travel path. The track is installed along its length. When positioning the auxiliary trolley, the Gray busbar is installed parallel to the auxiliary trolley's track, ensuring that the installation length of the Gray busbar covers the entire running length of both the main and auxiliary trolleys. Furthermore, electromagnetic matching devices are also installed on both the main and auxiliary trolleys to identify their positions. The electromagnetic matching devices move parallel to the Gray busbar without contact; the point pointed to by the electromagnetic matching device is the current position value. Displacement can be obtained on the vehicle or ground without an initial reference point, achieving a positioning accuracy within 20 mm and a resolution of 5 mm. Intermittent or continuous detection is possible. Simultaneously, both the main and auxiliary trolleys are equipped with position detection sensors with reset points. Specifically, Profinet fieldbus communication is used, connecting to the PLC control module. Accurate vehicle positioning is achieved through precise position signals combined with the closed-loop position control program in the PLC control module.

[0040] Furthermore, for precise positioning of the hoisting mechanism, an absolute rotary encoder is coaxially mounted on the hoisting drum for positioning. A dual-contact travel limit switch is also coaxially mounted on the hoisting drum for deceleration and stop limits. A proximity switch is also installed on the hoisting drum, and a calibration angle iron is installed on the side of the drum. Calibration is performed once per revolution of the drum. The absolute rotary encoder used is a Pepperl+Fuchs EN58IL series magnetic absolute rotary encoder, a Profinet interface absolute rotary encoder based on the magnetoelectric sampling principle. To achieve precise control and rapid response in three-dimensional positioning, closed-loop control is used for the motor. Incremental encoders can be added to both the hoisting mechanism motor and the traveling mechanism motor. When the motor rotates, the incremental encoder continuously outputs pulse signals. Each pulse signal corresponds to a tiny movement of the motor shaft. The number of pulses can be recorded by the counter of the drive control unit and converted into the motor speed, which is then further controlled by the drive control unit.

[0041] In one embodiment, the PLC control system further includes a safety protection module; the safety protection module includes mechanical limit switches, proximity switches, and radar ranging devices. The mechanical limit switches are located at both ends of the traveling rail where the traveling mechanism is located, the proximity switches are located on the traveling rail and maintain a preset distance from the mechanical limit switches, and the radar ranging devices are located on both sides of the traveling mechanism; the proximity switches and the radar ranging devices are respectively connected to the PLC controller.

[0042] In this embodiment, the safety protection module adopts a combination of mechanical limit and proximity switch, and is installed at the front and rear movement positions of the traveling mechanism to prevent collisions between the front and rear limits of the traveling mechanism. In addition, radar ranging devices are added on the left and right sides of the traveling mechanism. The maximum detection distance of the radar is 55m, and a further 6m anti-collision deceleration limit is set to prevent collisions.

[0043] In one embodiment, the automatic hooking system of the gantry crane further includes a position recognition system; the position recognition system includes an infrared thermal imager, which is installed below the main beam of the gantry crane for positioning the slag bag.

[0044] In this embodiment, the main working principle of the infrared thermal imager is to obtain an infrared image by performing planar imaging of the temperature of the hot slag bag, then identify the position of the hook in the infrared image, and then normalize the infrared coordinates and the coordinates of the traveling mechanism to the same coordinate system. Finally, based on the data in the same coordinate system, the coordinates of the hook in the slag bag are calculated to guide the main hook to engage.

[0045] Specifically, the location identification system provided in this application uses an infrared thermal imager to detect the location, shape, temperature, and other information of the slag bag. In an automated logistics or production system, the WMS (Warehouse Management System) is responsible for task scheduling and data management. The location identification system provided in this application can communicate with the WMS, that is, communicate via the TCP / IP protocol, to realize functions such as status monitoring, command issuance, and scan result feedback. The specific process is as follows:

[0046] First, the WMS system sends a WMS heartbeat message to the scanning system every 10 seconds. This is mainly used to monitor the connection between the WMS system and the scanning system. If the scanning system does not receive this message for an extended period, it may be considered a communication interruption. Next, the WMS system sends a start-scan command to the scanning system. This occurs when the WMS system detects a slag bag, indicating an object to be scanned, and the gantry crane is in position, meeting the scanning requirements. Then, the scanning system sends a scan heartbeat message to the WMS system every 10 seconds. This helps the WMS system determine if the system is online or experiencing any abnormalities. Following this, the scanning system sends a scan-end command to the WMS system. After completing the scanning task, the scanning results, such as the location, size, and temperature of the slag bag, are packaged and sent to the WMS system as crucial data for subsequent automatic hooking and path planning. Finally, if the scanning system malfunctions, it sends a scan system abnormality command to the WMS system for timely handling of the abnormality or switching to a backup system.

[0047] Furthermore, the position recognition system also includes a laser rangefinder and a stop structure; the stop structure is set on the transport track where the slag bag is located to stop the slag bag at the initial hoisting position, and the laser rangefinder is set on one side of the initial hoisting position and is connected to the PLC controller.

[0048] In this embodiment, the location identification system, in addition to an infrared thermal imager, also includes a laser rangefinder and a stop structure that work together, specifically as follows: Figure 5 As shown, the infrared thermal imager is installed below the main beam, and the power and signal lines are connected to the electrical room. A laser ranging system is installed next to the initial hoisting position of the slag bag on the transport track. When the slag bag car arrives, the stop stops the car in the parking position. The slag bag car triggers the laser ranging sensor on the side to send a signal to the PLC controller. The PLC controller controls the infrared thermal imager to scan the slag bag parking position. After the scan is completed, the hoisting task is generated based on the confirmed scan results and after inputting the slag bag attributes.

[0049] In one embodiment, the PLC control system further includes a crane anti-sway module; the crane anti-sway module includes an anti-sway controller, a frequency converter, and a braking resistor. The anti-sway controller and the frequency converter are respectively connected to the PLC controller. The frequency converter is connected to the variable frequency motor of the crane mechanism and the variable frequency motor of the hoisting mechanism respectively based on Profinet bus communication. The braking resistor is connected in parallel with the DC bus of the frequency converter. The anti-sway controller is used to calculate the target data curve based on the working status information of the hook device and send the target speed curve to the PLC controller, so that the PLC controller controls the frequency converter and the braking resistor to work to adjust the running speed of the crane mechanism and the hoisting mechanism.

[0050] In this embodiment, the crane anti-sway module is specifically used to realize closed-loop speed control of each mechanism. It mainly includes an anti-sway controller, a frequency converter, and anti-sway software. Specifically, when the crane mechanism is running, the optimal speed of the crane is calculated based on the lowering height of the lifting device, so that the crane mechanism can smoothly reach the target position. Automatic electrical anti-sway of the crane mechanism is achieved by controlling the acceleration and speed of the crane mechanism. When the crane anti-sway module alarms or malfunctions, it sends the alarm or malfunction information to the PLC controller. The anti-sway controller uses the feedback of the changing angle to calculate a reasonable speed setpoint for the trolley and crane. The PLC controller sends the processed setpoint to the transmission mechanism to control the movement of the crane mechanism.

[0051] Specifically, the inverter selected is the Huichuan CS710-4T series inverter. To improve the inverter's command reception rate, enhance information interaction between the inverter and the PLC controller, and fully utilize the PLC controller's diagnostic functions, ProfiNet bus communication is adopted to communicate with the inverters of the main trolley, auxiliary trolley, and hoisting mechanism, meeting bus control requirements and achieving performance characteristics such as precise positioning and rapid anti-sway. Furthermore, according to the law of conservation of energy, when the lifting device is lowered, the gravitational potential energy needs to be converted into electrical energy and released through the braking resistor. 60% of the rated power of the main hook and auxiliary hook motors, i.e., 54KW and 33KW, is selected as the braking resistor power. When the traveling mechanism moves, the dynamic potential energy of the traveling mechanism needs to be converted into electrical energy and released through the braking resistor. 40% of the power of the main trolley and auxiliary trolley motors, i.e., 36KW and 22KW, is selected as the braking resistor power.

[0052] In one embodiment, the gantry crane automatic hooking system further includes a remote control system; the remote control system includes a central control room control system, a driver's cab control system, and an auxiliary system. The central control room control system and the driver's cab control system are respectively connected to the PLC control system. The central control room control system is used to execute fully automatic control mode or remote manual control mode for the gantry crane. The driver's cab control system is installed on the gantry crane and is used to execute manual operation mode for the gantry crane. The auxiliary system is used to ensure the stable operation of the remote control system.

[0053] In this embodiment, the gantry crane can realize three control modes: fully automatic control mode, remote manual control mode, and manual operation mode. After authorization from the central control room, the operation mode can be selected as needed.

[0054] Specifically, the central control room is located far from the construction site to ensure that control personnel are away from the operating area of ​​the automatic gantry crane. In fully automatic control mode, planning information from the upper-level system is sent to the intelligent warehouse management system server, which then parses the planning commands and sends them to the dispatching system server. The PLC control system executes the commands through a compiled instruction set, and finally, the completed task is fed back to the dispatching system server. In this operating mode, only personnel are needed in the central control room. The remote manual control mode requires the addition of two sets of linkage operation devices in the central control room. The original operating mode is retained, and manual remote control operation of specific crane mechanisms can be performed based on video signals. When the crane mechanism is selected as the manual control mode, the crane can be remotely operated, and the work completion command is returned. The manual operation mode retains the original gantry crane body driver's cab operation mode. When manual intervention is required, the operator can control the crane through the driver's cab. The above three operating modes can be freely switched. When a crane switches modes, it does not affect the automatic operation of other cranes. When switching back from manual mode to automatic mode, the crane dispatching system can quickly take over the crane and assign appropriate tasks.

[0055] In addition, the auxiliary system involves installing a ground control cabinet in the electrical room, and installing sprinkler valves, physical fences, Gray busbars, decoders, ground monitoring, lighting, and fixed-end wireless WIFI equipment in the slag bag area. The power supply and signal lines are connected to the ground control cabinet, with a total load power of 10KW. External power supply cables are introduced into the ground control cabinet in the electrical room. According to the equipment layout diagram of the remote control room, the driving linkage console, central control dispatch computer and interactive platform computer, 60-inch monitoring display screen, and remote control cabinet are installed in the control room. Cable trays are laid inside, with a total load power of 5KW for the internal equipment. External power supply cables are introduced into the control room, and the grounding resistance must not exceed 4Ω. The remote control cabinet will have a reserved digital fiber optic interface.

[0056] In summary, the PLC control system architecture provided in this application is as follows: Figure 6As shown, the system is specifically divided into upper-layer control and communication, middle-layer control and processing, and lower-layer execution and feedback. In the upper-layer control and communication, wireless APs provide wireless network access points for remote monitoring and data transmission. Switches, as the core devices of the wired network, connect various subsystems to achieve data exchange and communication. In the middle-layer control and processing, the PLC controller, as the core controller, is responsible for receiving data from various sensors and devices and performing logical operations and control outputs according to preset programs. Industrial control computers are used for more complex calculations, data processing, and human-machine interfaces. In the lower-layer execution and feedback, frequency converters control the speed and torque of variable frequency motors, achieving smooth start and stop by adjusting voltage and frequency. Encoders are installed on the motors to monitor and feedback position information to the PLC controller in real time to ensure precise control. Radar rangefinders are used to measure distances for collision avoidance or positioning functions. Limit switches limit the travel range of mechanical devices to prevent overtravel damage. Scanners detect the position, shape, and other information of objects. The main trolley Gray bus and auxiliary trolley Gray bus in the crane mechanism are used for crane positioning.

[0057] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0058] The above embodiments are merely illustrative of several implementation methods of this application, and their descriptions are relatively specific and detailed. However, they should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. An automatic hooking system for a gantry crane, characterized in that, Includes a gantry crane, slag bag (1), hook device and PLC control system; The slag bag (1) is provided with lifting lugs (2) on both sides, and the bottom of the slag bag (1) is hinged with a movable bottom hook (3); the gantry crane includes a traveling mechanism and a hoisting mechanism, the hook device is connected to the traveling mechanism through the hoisting mechanism, the traveling mechanism is used to drive the hook device to move above the slag bag (1), the hoisting mechanism is used to drive the hook device to move vertically along the slag bag (1), the hook device includes a vision acquisition unit, a main hook lifting tool and a secondary hook lifting tool, the main hook lifting tool is used to hook the lifting lugs (2), the secondary hook lifting tool is used to hook the movable bottom hook (3), the vision acquisition unit is used to acquire the hooking image of the main hook lifting tool and the lifting lugs (2), wherein the main hook lifting tool and the secondary hook lifting tool are both double lifting point lifting tools; The PLC control system includes a PLC controller and a positioning module. The PLC controller is connected to the positioning module, the traveling mechanism, and the hoisting mechanism, respectively. The positioning module is used to position the traveling mechanism and the hoisting mechanism.

2. The automatic hooking system for gantry cranes according to claim 1, characterized in that, The traveling mechanism includes a main trolley and an auxiliary trolley. The main trolley is mounted on the main beam of the gantry crane, and the auxiliary trolley is mounted on the auxiliary beam of the gantry crane. The main hook lifting device includes a main hook (4) corresponding to the lifting lug (2), the main hook (4) is connected to the lifting mechanism for transmission and is used to hook with the lifting lug (2); The auxiliary hook lifting device includes a balance beam (5) and an auxiliary hook (6). The balance beam (5) is connected to the lifting mechanism. Both ends of the balance beam (5) are provided with a movable pulley group. A horizontal tilt sensor is provided on the balance beam (5). The auxiliary hook (6) includes a flexible lifting device (601) and a V-shaped steel bar (602) connected to each other. One end of the flexible lifting device (601) is flexibly connected to the movable pulley group, and the other end of the flexible lifting device (601) is connected to the V-shaped steel bar (602). The V-shaped steel bar (602) is used to hook with the movable bottom hook (3). The opening direction of the main hook (4) is opposite to that of the secondary hook (6).

3. The automatic hooking system for gantry cranes according to claim 2, characterized in that, The visual acquisition unit includes multiple 3D detection cameras (7); The 3D detection camera (7) is set on the main trolley close to the main hook (4), and the 3D detection camera (7) is aimed at the hook connection between the main hook (4) and the lifting lug (2) to collect the hook connection image between the main hook (4) and the lifting lug (2).

4. The automatic hooking system for gantry cranes according to claim 1, characterized in that, The movable bottom hook (3) includes a fixed connecting section (301) and a movable connecting section (302); The first end of the fixed connection section (301) is fixedly connected to the bottom of the slag bag (1); The first end of the movable connecting section (302) is hinged to the second end of the fixed connecting section (301), and the second end of the movable connecting section (302) is used to hook with the auxiliary hook lifting device.

5. The automatic hooking system for gantry cranes according to claim 1, characterized in that, The positioning module includes a vehicle positioning unit and a lifting positioning unit; The trolley positioning unit includes a Gray bus, an electromagnetic matching device, and a position detection sensor. The Gray bus is installed on the trolley track where the trolley mechanism is located. The electromagnetic matching device is installed on the trolley mechanism. The Gray bus and the electromagnetic matching device maintain a non-contact relative motion state to obtain the position information of the trolley mechanism. The position detection sensor is set on the trolley mechanism and is connected to the PLC controller via Profinet bus communication. The hoisting mechanism includes a hoisting drum. The main hook and the auxiliary hook are respectively connected to the traveling mechanism through the hoisting drum. The hoisting positioning unit includes an absolute rotary encoder, a dual-contact limit switch, a proximity switch, and a calibration angle iron. The absolute rotary encoder is coaxially mounted with the hoisting drum. The dual-contact limit switch is located on the hoisting drum. The proximity switch and the calibration angle iron are located on the side of the hoisting drum.

6. The automatic hooking system for gantry cranes according to claim 1, characterized in that, The PLC control system also includes a safety protection module; The safety protection module includes mechanical limiters, proximity switches, and radar ranging devices. The mechanical limiters are located at both ends of the traveling track where the traveling mechanism is located. The proximity switches are located on the traveling track and maintain a preset distance from the mechanical limiters. The radar ranging devices are located on both sides of the traveling mechanism. The proximity switch and the radar ranging device are respectively connected to the PLC controller.

7. The automatic hooking system for gantry cranes according to claim 1, characterized in that, The gantry crane automatic hooking system also includes a position recognition system; The location identification system includes an infrared thermal imager, which is installed below the main beam of the gantry crane for positioning the slag bag.

8. The automatic hooking system for gantry cranes according to claim 7, characterized in that, The location identification system also includes a laser rangefinder and a stop structure; The stop structure is installed on the transport track where the slag bag is located, and is used to stop the slag bag at the initial hoisting position. The laser rangefinder is installed on one side of the initial hoisting position and is connected to the PLC controller.

9. The automatic hooking system for a gantry crane according to claim 1, characterized in that, The PLC control system also includes a vehicle anti-sway module; The anti-sway module for the crane includes an anti-sway controller, a frequency converter, and a braking resistor. The anti-sway controller and the frequency converter are respectively connected to the PLC controller. The frequency converter is connected to the variable frequency motor of the crane mechanism and the variable frequency motor of the hoisting mechanism based on Profinet bus communication. The braking resistor is connected in parallel with the DC bus of the frequency converter. The anti-sway controller is used to calculate the target data curve based on the working status information of the hook device, and send the target speed curve to the PLC controller, so that the PLC controller controls the frequency converter and the braking resistor to work, thereby adjusting the running speed of the traveling mechanism and the hoisting mechanism.

10. The automatic hooking system for a gantry crane according to claim 1, characterized in that, The gantry crane automatic hooking system also includes a remote control system; The remote control system includes a central control room control system, a driver's cab control system, and an auxiliary system. The central control room control system and the driver's cab control system are respectively connected to the PLC control system. The central control room control system is used to execute fully automatic control mode or remote manual control mode for the gantry crane. The driver's cab control system is installed on the gantry crane and is used to execute manual operation mode for the gantry crane. The auxiliary system is used to ensure the stable operation of the remote control system.

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