Automatic hopper tipping system and method for scrap charging crane

Abstract

This invention provides an automatic trough tilting system and method for a scrap steel feeding crane. The system includes main and auxiliary lifting mechanisms and main and auxiliary trolleys; the main and auxiliary lifting points are respectively located in front of and behind the scrap steel trough. During the tilting process, the system sets a fixed auxiliary lifting speed, uses a plane geometric transformation algorithm to calculate the trough tilting angle in real time, and simultaneously obtains the target operating speeds of the auxiliary trolley and the main lifting mechanism for follow-up control, thereby completing the automated tilting. This invention replaces the manual operation of the four mechanisms with automated control, supports remote control, and eliminates the need for personnel to approach the high-temperature, dense smoke furnace opening for observation. This reduces operational difficulty, improves the working environment, and effectively ensures the safety and reliability of the feeding process.

Description

Technical Field

[0001] This invention relates to the field of crane automation control technology, specifically to an automatic trough tilting system and method for a scrap steel feeding crane. Background Technology

[0002] my country is a major steel producer. Although iron ore remains the primary raw material for steelmaking, the tense international economic situation has led to limited iron ore procurement and rising prices, resulting in a continuous increase in steelmaking costs. To alleviate this situation, using scrap steel as a raw material for steelmaking is an important direction for the green transformation of the steel industry.

[0003] Scrap steelmaking offers economic advantages such as low cost, low energy consumption, and low investment, while significantly reducing carbon footprint and pollution emissions in terms of environmental protection and resource utilization. Scrap steel can directly replace raw materials such as iron ore and coke, eliminating high-cost processes such as mining, beneficiation, and coking. Compared to the long-process (blast furnace-converter) steelmaking, short-process steelmaking can save more than 60% of energy, reduce comprehensive energy consumption per ton of steel by approximately 50% to 60%, and reduce CO2 emissions per ton of steel by approximately 1.6 tons. Simultaneously, it produces almost no dust, SO2, or NOx generated during coking and sintering processes. x Pollutants such as iron ore and coking coal are generated. Realizing the resource utilization of scrap steel not only reduces land occupation and the consumption of natural resources, aligning with the circular economy policy, but also effectively reduces the demand for imported iron ore and coking coal, enhancing national resource security.

[0004] Therefore, major steel mills in China widely use scrap steel in steelmaking. In the scrap steelmaking process, scrap steel feeding cranes are needed, with tilting scrap steel feeding cranes being widely used. However, because the furnace opening produces large amounts of dense smoke and flames during feeding, the crane operators' visibility is severely obstructed, and the high temperature and dust environment makes the working conditions extremely harsh. Furthermore, when adding scrap steel to molten iron in an open furnace opening, if the scrap steel contains moisture or is from a sealed metal container, it can lead to a violent explosion, potentially causing molten iron to splash and resulting in injury or death.

[0005] Therefore, developing an automatic trough tilting system for scrap steel feeding cranes to achieve automated trough tilting control, enabling operators to operate the system remotely without close observation, is of great significance for significantly improving production safety, reducing personal safety threats to operators, and improving feeding efficiency and reliability. Summary of the Invention

[0006] To address the shortcomings of existing technologies, the purpose of this invention is to provide an automatic trough tilting system and method for a scrap steel feeding crane.

[0007] An automatic trough tilting system for a scrap steel feeding crane according to the present invention includes: a main lifting mechanism, an auxiliary lifting mechanism, a main trolley, and an auxiliary trolley; The lifting point of the main lifting mechanism is located in front of the scrap steel trough, and is connected to and controlled by the main trolley for horizontal displacement; the lifting point of the auxiliary lifting mechanism is located behind the scrap steel trough, and is connected to and controlled by the auxiliary trolley for horizontal displacement. The system controls the auxiliary hoist to operate at a set speed, calculates the tilting angle of the scrap steel trough in real time, and uses a plane geometric transformation algorithm to calculate the target operating speed of the auxiliary trolley and the main hoisting mechanism in real time, thereby realizing the automated tilting of the scrap steel trough.

[0008] Preferably, the tilting process of the scrap steel trough is geometrically calculated with the connection point of a bottom base near the furnace opening in front of the trough as the rotation center.

[0009] Preferably, the system employs time slices. The rotation angle of the scrap steel trough is calculated using differential time. The calculation formula is:

[0010] in, The lifting speed of the auxiliary lifting mechanism, The initial height of the auxiliary lifting point from the center of rotation. It is the straight-line distance between the auxiliary lifting point and the center of rotation.

[0011] Preferably, the target operating speed of the auxiliary vehicle The calculation formula is:

[0012] in, The angle between the line connecting the auxiliary lifting point and the rotation center and the horizontal plane, and... .

[0013] Preferably, the formula for calculating the target operating speed Vb of the main hoisting mechanism is:

[0014] in, The length distance between the main lifting point and the center of rotation.

[0015] Preferably, the system collects the weight data of the main lifting mechanism and the auxiliary lifting mechanism in real time during operation, and determines whether the trough touches the bottom or the equipment interferes during the tipping process based on the changes in the weight information.

[0016] An automatic trough tipping method for a scrap steel feeding crane according to the present invention includes the following steps: Step S1: Manually operate the crane to move the scrap steel hopper to the furnace opening feeding position, and then switch to the automatic tilting control mode after it is ready; Step S2: Initialize system variables and check whether the system interlocking conditions are met; Step S3: Calculate the time slice The duration of the time, and the operating speed of the auxiliary lifting mechanism are set. ; Step S4: Calculate the current tilt angle, calculate and set the auxiliary trolley running speed and the main lifting speed, and send the calculated speed to the mechanism's control program to achieve speed adjustment; Step S5: Determine whether the current tilt angle has reached the preset feeding angle; if not, call the safety detection subroutine to check the safety status, and repeat the judgment process of speed calculation after the time slice has elapsed.

[0017] Preferably, the specific steps for calculating the time slice t are as follows: Based on the data from the system's tick counter, obtain the current system tick counter data; Calculate the difference between the current system tick counter data and the tick counter data saved in the previous time slice to obtain the duration of the current time slice t; After each calculation is completed, the data of the current system tick counter is saved for the difference calculation of the next time slice.

[0018] Preferably, the method further includes: Control the shutdown of all mechanisms and wait for a preset period of time; Collect the lifting capacity data of the main hoisting mechanism and the auxiliary hoisting mechanism; When the lifting weight data is determined to be lower than the set threshold, the feeding is considered complete.

[0019] Preferably, it further includes: Step S6: Set the return angle and the return operating speed of the auxiliary lifting mechanism; During each time slice of the return process, the auxiliary trolley, main lifting mechanism, and auxiliary lifting mechanism are controlled to run in the opposite direction of the feeding process; Once the rotation angle of the scrap steel trough reaches the return angle and returns to a horizontal state, the operation of all mechanisms stops and the automatic trough tilting process exits.

[0020] Compared with the prior art, the present invention has the following beneficial effects: 1. This invention uses automated control to move the various mechanisms of a crane, transforming the high-risk operation that originally required close observation into remote or remote control operation. This keeps operators away from high temperatures, dense smoke, flames, and potential hazards of splashing and explosion, greatly improving the working environment and reducing threats to personal safety.

[0021] 2. This invention is based on a planar geometric transformation algorithm, which uses time slices as differential time to calculate the target speed in real time, reducing the difficulty of manual four-mechanism linkage operation and realizing a more stable, efficient and reliable automatic feeding action.

[0022] 3. This invention verifies the weight data of the main and auxiliary lifting devices in real time during the tilting and return processes. If the weight suddenly decreases, it can promptly identify the risk of the trough hitting the bottom or the wire rope slack, thus preventing unhooking accidents. If the weight suddenly increases, it can promptly identify the risk of interference or obstruction, thus preventing equipment damage and ensuring equipment safety in all aspects. Attached Figure Description

[0023] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings: Figure 1 A simplified geometric calculation diagram of the trough tilting action provided in an embodiment of the present invention; Figure 2 A schematic diagram illustrating the formation process of the simplified calculation diagram of the scrap steel trough provided in an embodiment of the present invention; Figure 3 This is a simplified geometric calculation diagram of the main hoisting mechanism according to an embodiment of the present invention; Figure 4 This is a flowchart of the automatic trough tilting control process according to an embodiment of the present invention. Detailed Implementation

[0024] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0025] like Figure 1 and Figure 2 As shown, this embodiment of the invention provides an automatic trough tilting system for a scrap steel feeding crane, designed to automatically tilt the scrap steel trough. The lifting and tilting of the scrap steel trough requires the cooperation of two lifting mechanisms: a main lifting mechanism and an auxiliary lifting mechanism. The lifting point of the main lifting mechanism is located in front of the scrap steel trough, and the main trolley is connected to the main lifting mechanism and controls its horizontal displacement. The lifting point of the auxiliary lifting mechanism is located behind the scrap steel trough, and the auxiliary trolley is connected to the auxiliary lifting mechanism and controls its horizontal displacement.

[0026] like Figure 2 The diagram shown illustrates the formation process of the simplified calculation diagram of the scrap steel trough according to the present invention. In actual working conditions, the scrap steel trough typically has four lifting lugs, i.e., four lifting points (two in the front and two in the back). Since the two front lifting points move synchronously during the tilting operation, and the two rear lifting points also move synchronously, the geometric and kinematic calculations can be simplified to two lifting points: the rear is designated as lifting point 1, and the front as lifting point 2. The tilting process of the scrap steel trough uses the connection point of the bottom base near the furnace opening at the front of the trough as the center of rotation. Since the calculation process only needs to consider the geometric relationship between the lifting point and the center of rotation, the following results are obtained: Figure 2 The simplified calculation diagram of the dashed line section: Lifting point 1 is simplified to point A, lifting point 2 is simplified to point C, and the rotation center is point O. In the initial design or lifting preparation state, points A and C can be approximately considered to be at the same horizontal height. Although there may be slight deviations in reality, these deviations do not affect the calculation accuracy of this system.

[0027] In traditional manual operation, to simplify operations and ensure safety and reliability, the tipping of the scrap hopper is typically controlled by the operator. The main hoist is first slightly angled forward and held stationary, then the auxiliary hoist is raised at a fixed speed, with the auxiliary trolley and main hoist simultaneously controlled. Specifically, the crane is usually equipped with operating handles; the auxiliary hoist and auxiliary trolley share the same cross-shaped operating handle, while the main hoist and main trolley share another. The operator only needs to push the auxiliary hoist to a fixed working position, then control the auxiliary trolley by moving the handle left and right, and simultaneously pull the main hoist handle to control the main hoist. Controlling these two core actions completes the entire tipping operation, significantly reducing operational difficulty compared to a fully interconnected four-mechanism system, thus ensuring reliability and safety.

[0028] The automated system flow of this invention is designed based on the aforementioned manual operation flow. First, the crane needs to be manually operated to move the scrap steel hopper to the furnace feeding position. Once ready, the operator switches the system to automated tilting control mode. In this mode, the main trolley remains stationary, and the automated tilting control system controls the speed of the crane's auxiliary trolley, auxiliary lifting mechanism, and main lifting mechanism. The system operates on time slices. As a differential time interval, the height of the auxiliary hoist is continuously monitored to calculate the positions of the auxiliary trolley and the main hoist, and then the speeds of the auxiliary trolley and the main hoist are calculated. The system sends the calculated target operating speed to the underlying control program of the corresponding mechanism to achieve speed adjustment of the mechanism, and finally completes the tipping control of the scrap steel trough.

[0029] Furthermore, during this automation process, the system collects real-time lifting weight data from both the main and auxiliary hoists and constantly verifies the weight information to ensure it is normal. Normally, the weight will not change abruptly before reaching the desired tipping angle, nor will it suddenly drop to the unloaded weight. If the weight suddenly becomes lighter, it usually means the trough may have hit the bottom, which could cause the hoisting wire rope to slack, easily leading to a dangerous unhooking accident. Conversely, if the weight suddenly increases, it means there is obstruction during tipping, potentially interfering with other surrounding equipment, easily causing equipment damage or detachment accidents. By verifying weight information in real time, production accidents can be greatly reduced.

[0030] like Figure 1 As shown, it demonstrates the use of Figure 2 Based on a simplified calculation graph, the scrap steel trough rotates from a horizontal position. The geometric relationship between the two states after the angle. (In time slices) Inside, lifting point 1 of the scrap steel trough rotates from point A to point B, and lifting point 2 rotates from point C to point D. O is the center of rotation, and the rotation angle is... Correspondingly, the auxiliary trolley moves from position X1 to position X2, with a moving distance of S1, and the height change of the auxiliary lifting mechanism (lifting point 1) is H.

[0031] By simple measurement or based on the mechanical design drawings of the scrap steel trough, the system can pre-determine the straight-line distance L between the auxiliary lifting point A and the rotation center O, as well as the vertical distance H0 between point A and the lower reference plane E.

[0032] therefore, Figure 1 The angle of ∠AOE It can be calculated using the following formula:

[0033] Given that the initial lifting height of the auxiliary hoist is... The scrap steel trough rotates The height after degrees is Therefore, the change in the height of the auxiliary lift. for:

[0034] Although the control speed of the auxiliary hoist is set in the control process, the actual hoisting speed of the auxiliary hoist is adjusted to improve the accuracy of position calculation. It can be based on the time slice time. and the detected actual height change The calculation shows that:

[0035] Based on the above geometric relationships, the rotation angle of the scrap metal trough in the current time slice can be calculated. :

[0036] Then, the displacement of the auxiliary trolley was calculated. :

[0037] Then, the target running speed of the auxiliary trolley in the current time slice can be calculated. :

[0038] At this point, the next running speed of the auxiliary trolley has been calculated. .

[0039] Next, calculate the operating speed of the main hoist. For example... Figure 3 The diagram shown illustrates the computational geometry of the main hoisting point's movement from point C to point D. Let the angle ∠DOC be... The length of DO (i.e., the distance between the main lifting point D and the rotation center O) is The length of the main hoisting wire rope is from Figure 1 CX0 in the middle changes to DX0.

[0040] From geometric relations, we can obtain:

[0041] Calculate the arc length swept by the rotation :

[0042] The angle calculation uses radians, due to the time slice. Very small, combined with a very long main hoisting wire rope, that is... Figure 1 CX0 and DX0 in the time slice are very long, so in the time slice The change in the length of the main hoisting wire rope within a given time period can be approximated by... Figure 3 arc length To express.

[0043] Therefore, the target operating speed of the main lifting mechanism is obtained. :

[0044] At this point, the operating speed of the auxiliary lifting unit will be... and the operating speed of the main hoist All calculations are complete. The system will... and The speed setpoint is used to control the operating speed of the auxiliary and main hoists, and the current coordinate and angle data are recorded. Based on this, in the next time slice... By repeating the above calculation steps, the speed of the auxiliary trolley and the main lifting speed at each subsequent differential moment can be obtained, thus realizing automated speed follow-up control throughout the entire process.

[0045] like Figure 4 The diagram shows the system control operation flowchart of the present invention, and its specific steps are as follows: Step S1: Manual Operation and Mode Switching. First, the crane needs to be manually operated to move the scrap steel hopper to the furnace opening feeding position. Once ready, the operator switches to the automated tilting control mode to start the system's automated process.

[0046] Step S2: Data Initialization and Condition Judgment. The system enters the data initialization procedure, initializing known data (such as mechanism parameters) into the initialization sequence. , , (etc.) Initialize variables. Then check whether a series of safety and operational interlocking conditions of the system are met. If all are ready, start the system control flow; otherwise, wait for the conditions to be ready.

[0047] Step S3: Time Slice and Velocity Calculation. Calculate the time slice. The time slice is calculated based on the system's tick counter data to ensure accuracy. After each calculation, the system saves the current tick counter data. At the next time slice, the difference between the current tick counter data and the previously saved data is calculated to determine the precise time slice. The length of time. Typically, a time slice. The time limit is set between 0.1 and 0.5 seconds. Due to the short duration, the speed response of the auxiliary trolley and the main hoist is basically lag-free during system operation.

[0048] Subsequently, the operating speed of the auxiliary lifting unit was set. The system calculates the current tilt angle. During the first time slice of the automated process, the system defaults to a tilt angle of 0. At this point, the auxiliary trolley speed and main lifting speed are calculated. Since the saved previous system tick counter data is invalid at the initial moment, and the tilt angle is 0, the calculated auxiliary trolley speed and main lifting speed are also zero. Only from the second time slice onwards can the system calculate and output valid follow-up speed data.

[0049] Step S4: Safety Detection and Cyclic Control. After the calculation is completed in each time slice, the system determines whether the current tilt angle has reached the preset feeding angle.

[0050] If the target is not reached, a safety check subroutine is invoked to check the safety status. This safety check includes threshold judgments for the lifting capacity of the main and auxiliary cranes, as well as status checks for other safety interlocks. When an alarm state is detected, such as a sudden change in lifting capacity indicating bottoming out or interference, the system will immediately terminate the operation of all mechanisms in the safety check subroutine and completely terminate the automated operation process to ensure safety.

[0051] If the security check passes, the system waits for the next time slice to arrive (usually during this waiting period, the system will execute other background tasks). When the next time slice arrives, the system returns to step S3 and repeats the above-described process of calculating and judging distance, angle, and speed.

[0052] Step S5: Feeding Completion Judgment. When the system detects that the tilting angle has reached the preset feeding angle, it stops the operation of all mechanisms. The system enters the feeding completion judgment process, during which a period of time is required, followed by data collection of the lifting weight. The system determines the feeding completion status based on both the lifting weight of the main and auxiliary lifters and the waiting time. When the determined lifting weight is lower than a preset threshold, feeding is confirmed as complete.

[0053] Step S6: Return Process. After determining that feeding is complete, the system automatically enters the return process. First, set the target return angle and the auxiliary lifting return speed. .

[0054] The return process is also based on time slices, and the calculation process is exactly the same as the feeding process described above. The tilt angle and the target speed of the main and auxiliary lifting mechanisms are calculated and set sequentially. The only difference is that the running speed direction of each mechanism is opposite to that during feeding. Within each time slice of the return process, the system also verifies whether the return angle has been reached. If it has not been reached, the safety detection subroutine is called to determine the status of the safety interlock and waits for the next time slice to arrive.

[0055] Step S7: Process End. Once the system detects and determines that the rotation angle of the scrap steel trough has returned to a horizontal state, i.e., reached the preset return angle, it will stop the operation of all mechanisms and then exit the automatic tilting system's operation process, thus successfully completing the entire automated feeding task.

[0056] In the description of this application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0057] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. A scrap charging crane automatic hopper tipping system, characterized in that, include: Main hoisting mechanism, auxiliary hoisting mechanism, main trolley and auxiliary trolley; The lifting point of the main lifting mechanism is located in front of the scrap steel trough, and is connected to and controlled by the main trolley for horizontal displacement; the lifting point of the auxiliary lifting mechanism is located behind the scrap steel trough, and is connected to and controlled by the auxiliary trolley for horizontal displacement. The system controls the auxiliary hoist to operate at a set speed, calculates the tilting angle of the scrap steel trough in real time, and uses a plane geometric transformation algorithm to calculate the target operating speed of the auxiliary trolley and the main hoisting mechanism in real time, thereby realizing the automated tilting of the scrap steel trough.

2. The automatic trough tilting system for a scrap steel feeding crane according to claim 1, characterized in that, The tilting process of the scrap steel trough is geometrically calculated with the connection point of the bottom base near the furnace opening in front of the trough as the center of rotation.

3. The automatic trough tilting system for a scrap steel feeding crane according to claim 2, characterized in that, The system uses time slices. The rotation angle of the scrap steel trough is calculated using differential time. The calculation formula is: in, The lifting speed of the auxiliary lifting mechanism, The initial height of the auxiliary lifting point from the center of rotation. It is the straight-line distance between the auxiliary lifting point and the center of rotation.

4. The automatic trough tilting system for a scrap steel feeding crane according to claim 3, characterized in that, The target operating speed of the auxiliary vehicle The calculation formula is: in, The angle between the line connecting the auxiliary lifting point and the rotation center and the horizontal plane, and... .

5. The automatic trough tilting system for a scrap steel feeding crane according to claim 4, characterized in that, The formula for calculating the target operating speed Vb of the main hoisting mechanism is as follows: in, The length distance between the main lifting point and the center of rotation.

6. The automatic trough tilting system for a scrap steel feeding crane according to claim 1, characterized in that, The system collects weight data of the main lifting mechanism and the auxiliary lifting mechanism in real time during operation, and determines whether the trough touches the bottom or the equipment interferes during the tipping process based on the changes in the weight data.

7. A method for automatically tilting the trough of a scrap steel feeding crane, based on the automatic trough tilting system of the scrap steel feeding crane according to any one of claims 1-6, characterized in that, Includes the following steps: Step S1: Manually operate the crane to move the scrap steel hopper to the furnace opening feeding position, and then switch to the automatic tilting control mode after it is ready; Step S2: Initialize system variables and check whether the system interlocking conditions are met; Step S3: Calculate the time slice The duration of the time, and the operating speed of the auxiliary lifting mechanism are set. ; Step S4: Calculate the current tilt angle, calculate and set the auxiliary trolley running speed and the main lifting speed, and send the calculated speed to the mechanism's control program to achieve speed adjustment; Step S5: Determine whether the current tilt angle has reached the preset feeding angle; If the time slice is not reached, the security check subroutine is called to check the security status, and the judgment process of speed calculation is repeated after the time slice is reached.

8. The automatic trough tilting method for a scrap steel feeding crane according to claim 7, characterized in that, The specific steps for calculating the duration of time slice t are as follows: Based on the data from the system's tick counter, obtain the current system tick counter data; Calculate the difference between the current system tick counter data and the tick counter data saved in the previous time slice to obtain the duration of the current time slice t; After each calculation is completed, the data of the current system tick counter is saved for the difference calculation of the next time slice.

9. The automatic trough tilting method for a scrap steel feeding crane according to claim 7, characterized in that, The method further includes: Control the shutdown of all mechanisms and wait for a preset period of time; Collect the lifting capacity data of the main hoisting mechanism and the auxiliary hoisting mechanism; When the lifting weight data is determined to be lower than the set threshold, the feeding is considered complete.

10. The automatic trough tilting method for a scrap steel feeding crane according to claim 9, characterized in that, It also includes step S6: Set the return angle and the return operating speed of the auxiliary lifting mechanism; During each time slice of the return process, the auxiliary trolley, main lifting mechanism, and auxiliary lifting mechanism are controlled to run in the opposite direction of the feeding process; Once the rotation angle of the scrap steel trough reaches the return angle and returns to a horizontal state, the operation of all mechanisms stops and the automatic trough tilting process exits.

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