PLC (Programmable Logic Controller) control method for automatic transportation of zinc stacks and related equipment

Abstract

The invention relates to the technical field of PLC automatic control, in particular to a PLC control method for zinc stack automatic transportation and related equipment. The method comprises the following steps: controlling a motor of a zinc sheet stacker crane through industrial Ethernet communication to obtain a layer thickness standard signal; a frequency converter of a zinc stack conveying line is triggered according to the layer thickness standard reaching signal, the zinc stack is moved through the zinc stack conveying line, and an arrival signal is obtained; the zinc stacks are transferred to an electric flat plate conveyor according to the sequence of the arrival signals, and the zinc stacks are horizontally moved to a first elevator through the electric flat plate conveyor; controlling a first elevator to lift the zinc stack to a starting position of a chain conveyor; and the zinc stacks are conveyed to the second elevator through the chain conveyor, the second elevator drives the zinc stacks to descend, and the zinc stacks descend to the target area to complete transportation of the zinc stacks. The control signal can be accurately obtained, the safe transportation environment is judged, equipment idling and zinc stack accumulation are avoided, and production continuity is guaranteed.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of PLC automation control, in particular to a PLC control method for automatic transportation of zinc stacks and related equipment. BACKGROUND

[0002] In the production process of zinc ingots, the automatic transportation control of zinc stacks relies on a decentralized centralized control system with PLC as the core. The system controls the frequency converters of the stacker, conveying line, elevator and other equipment through the PLC modules in each operation box with the help of PN communication, receives sensor signals such as photoelectric switches and proximity switches to realize a series of actions such as transfer, lifting and rotation of zinc stacks, thereby ensuring the continuous production. However, the existing control mode has many shortcomings: first, the control of PLC on the equipment depends on single sensor signal triggering, and in the complex environment of zinc dust and water vapor, the sensor is easily disturbed, leading to signal false alarm or omission, which makes PLC misjudge the position of zinc stacks, causing problems such as misplacement of conveying, equipment jamming and interrupting production process; second, the PN communication between distributed PLC modules and the main station and centralized monitoring system lacks a perfect emergency mechanism, and when the communication is delayed or interrupted, the control room is difficult to grasp the real-time state of the scene, and the abnormal operation of local equipment may affect the overall transportation rhythm, leading to zinc stack accumulation; third, the safety interlocking mechanism is not fully covered, and the protection of the cross region of equipment linkage is insufficient, and PLC cannot respond to potential safety hazards in time, increasing the probability of shutdown to handle safety accidents; fourth, the manual and automatic mode switching logic is ambiguous, and PLC is easy to fall into logical confusion due to operation conflicts, and has weak self-diagnosis ability for equipment failure, and the fault troubleshooting takes too long.

[0003] In summary, the technical problems in the related art need to be improved. SUMMARY

[0004] The main purpose of the embodiments of the present application is to provide a PLC control method for automatic transportation of zinc stacks and related equipment, which can accurately obtain control signals, judge safe transportation environment, avoid equipment idling and zinc stack accumulation, and ensure the continuity of production.

[0005] To achieve the above-mentioned purpose, one aspect of the embodiments of the present application provides a PLC control method for automatic transportation of zinc stacks, which comprises the following steps: controlling the motor of the zinc sheet stacker through industrial Ethernet communication to obtain a layer thickness standard signal; triggering the frequency converter of the zinc stack conveying line according to the layer thickness standard signal, moving the zinc stack through the zinc stack conveying line to obtain an arrival signal; According to the order of the arrival signal, the zinc stack is transferred to the electric flat conveyor, and the zinc stack is moved to the first elevator through the electric flat conveyor; Detecting the arrival of the zinc stack to the first elevator through a sensor; Transporting the zinc stack to the second elevator through the chain conveyor, and lowering the zinc stack to a target area through the second elevator to complete the transportation of the zinc stack.

[0006] In some embodiments, the sensor detection includes photoelectric switch detection and proximity switch detection; The photoelectric switch is used to detect whether the zinc stack reaches the start position of each device; The proximity switch is used to detect whether the action of each device reaches the stop position.

[0007] In some embodiments, the photoelectric switch and the auxiliary sensor simultaneously detect whether the zinc stack reaches the start position of each device; When the photoelectric switch and the auxiliary sensor remain consistent within a set time window, it is confirmed that the zinc stack reaches the start position of each device; The auxiliary sensor includes an ultrasonic sensor, a laser sensor, or an infrared sensor.

[0008] In some embodiments, the zinc sheet stacker, the electric flat conveyor, the first elevator, the chain conveyor, and the second elevator respectively communicate with the PLC through two independent industrial Ethernet cables; Redundant ring network technology is deployed at the network switch level through the two industrial Ethernet cables.

[0009] In some embodiments, it also includes a safety light curtain, an overload sensor, and a speed encoder; The safety light curtain, the overload sensor, and the speed encoder are respectively connected in communication with the PLC; The safety light curtain realizes signal hard-wired safety interlocking through safety PLC technology; The overload sensor is arranged at the motor of the zinc sheet stacker, the electric flat conveyor, the first elevator, and the second elevator; The speed encoder is arranged at the drive shaft of the chain conveyor; The overload sensor and the speed encoder are used for motor overload monitoring and chain speed anomaly detection of the device.

[0010] In some embodiments, the transferring of the zinc stack to the electric flat conveyor according to the arrival signals in the order of priority includes: When the new and old lines both send the arrival signal, the PLC automatically selects the delivery line with higher priority through a numerical comparison algorithm, and controls the electric flat conveyor to preferentially dock.

[0011] In some embodiments, the PLC control program acquires the frequency of the sensor signal jump in real time through the industrial Ethernet communication; In some embodiments, the PLC control program acquires the frequency of the sensor signal jump in real time through the industrial Ethernet communication; In some embodiments, the PLC control program acquires the frequency of the sensor signal jump in real time through the industrial Ethernet communication; In some embodiments, the PLC control program acquires the frequency of the sensor signal jump in real time through the industrial Ethernet communication; In some embodiments, the PLC control program acquires the frequency of the sensor signal jump in real time through the industrial Ethernet communication;

[0012] In some embodiments, the following steps are further included: In some embodiments, the following steps are further included: In some embodiments, the following steps are further included: In some embodiments, the following steps are further included:

[0013] To achieve the above-mentioned purposes, another aspect of the embodiments of the present application proposes a PLC control system for automatic transportation of zinc stacks, which comprises: A layer thickness confirmation module is configured to control the motor of a zinc sheet stacking machine through industrial Ethernet communication to obtain a layer thickness standard signal. A reaching signal generation module is configured to trigger the frequency converter of a zinc stack conveying line according to the layer thickness standard signal, move the zinc stack through the zinc stack conveying line, and obtain a reaching signal. A flat plate conveying module is configured to transfer the zinc stack to an electric flat plate conveyor according to the sequence of the reaching signals, and move the zinc stack to a first elevator through the electric flat plate conveyor. A first lifting module is configured to control the first elevator to lift the zinc stack to a chain conveyor starting position through a sensor detecting the movement of the zinc stack to the first elevator. A second lifting module is configured to convey the zinc stack to a second elevator through the chain conveyor, and the second elevator drives the zinc stack to descend to a target area to complete the transportation of the zinc stack.

[0014] To achieve the above object, another aspect of the embodiment of the present application provides a computer readable storage medium, which stores a computer program, and the computer program is executed by a processor to implement the method described above.

[0015] The embodiment of the present application at least has the following beneficial effects: the present application provides a PLC control method and related equipment for automatic transportation of zinc stacks, which communicates PLC with zinc sheet stacking machine, electric flat conveyor, first lifting machine, chain conveyor and second lifting machine through industrial Ethernet to control the full-automatic process of zinc sheet stacking and automatic transportation to the target area. The automatic connection between devices is realized through sensor signals and PLC logic control, reducing the delay caused by manual intervention, making the zinc stack transportation coherent and efficient; at the same time, the priority judgment mechanism of new and old zinc stack conveying line enables the electric flat conveyor to accurately dock the earliest arrived zinc stack, avoiding equipment idling and zinc stack accumulation, greatly improving the transportation rhythm. And local emergency stop and pause only affect specific equipment and do not interfere with global automatic operation, ensuring the continuity of production, providing reliable support for zinc ingot annual capacity, reducing the loss of production capacity caused by equipment failure or operation error, and improving the stability and economy of the overall production. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 is a flowchart of the PLC control method for automatic transportation of zinc stacks provided by the embodiment of the present application; Figure 2 is a structural schematic diagram of the PLC control system for automatic transportation of zinc stacks provided by the embodiment of the present application. DETAILED DESCRIPTION

[0017] In order to make the purpose, technical scheme and advantages of the present application clearer, the following will further describe the present application in combination with the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and do not limit the present application. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The implementation described in the following exemplary embodiments does not represent all the implementations consistent with the embodiment of the present application, but is only an example of devices and methods consistent with some aspects of the embodiment of the present application as described in the appended claims.

[0018] It can be understood that the terms "first", "second", and the like used in the present application can be used herein to describe various concepts, but unless specifically stated, these concepts are not limited by these terms. These terms are only used to distinguish one concept from another concept. For example, without departing from the scope of the embodiments of the present application, the first information can also be referred to as the second information, and similarly, the second information can also be referred to as the first information. Depending on the context, the word "if" as used herein can be interpreted as "when" or "upon" or "in response to determining".

[0019] The terms "at least one", "multiple", "each", "any", and the like used in the present application include one, two or more than two, multiple includes two or more than two, each refers to each of the corresponding multiple, and any refers to any one of the multiple.

[0020] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as understood by a person skilled in the art to which the present application belongs. The terms used herein are only for the purpose of describing the embodiments of the present application and are not intended to limit the present application.

[0021] Before the embodiments of the present application are described in detail, first, some nouns and terms involved in the embodiments of the present application are described, and the nouns and terms involved in the embodiments of the present application are applicable to the following explanations.

[0022] Distributed I / O module: scattered installation, connecting field devices and master station, collecting signals and executing instructions, simplifying wiring and improving system flexibility.

[0023] S7-1500 PLC master station: core control unit, coordinating distributed modules, processing signals, executing logic, and controlling device operation.

[0024] PN communication: based on Ethernet, realizing high-speed data transmission between PLC and device, supporting real-time control, and ensuring zinc stack transportation cooperation.

[0025] Control operation box: containing PLC, touch screen, local control device, monitoring and manual operation, linking field and control system.

[0026] MRP media redundancy protocol: realizing network link redundancy, quickly switching when failure, ensuring continuous communication, and reducing production interruption.

[0027] Figure 1 is an optional flowchart of the PLC control method for zinc stack automatic transportation provided by the embodiments of the present application, Figure 1 The method in the above method can include but is not limited to steps S100 to S500.

[0028] Step S100, the motor of the zinc sheet stacking machine is controlled through industrial Ethernet communication to obtain a layer thickness standard signal; Step S200, the frequency converter of the zinc stack conveying line is triggered according to the layer thickness standard signal, the zinc stack is moved through the zinc stack conveying line to obtain an arrival signal; Step S300, the zinc stack is transferred to the electric flat conveyor according to the sequence of the arrival signal, and the zinc stack is moved to the first elevator through the electric flat conveyor; Step S400, when the zinc stack is moved to the first elevator, the first elevator is controlled to lift the zinc stack to the starting position of the chain conveyor through the sensor; Step S500, the zinc stack is conveyed to the second elevator through the chain conveyor, the second elevator drives the zinc stack to descend to the target area to complete the transportation of the zinc stack.

[0029] The steps S100 to S500 shown in the embodiment of the application are communicated and connected with the zinc sheet stacking machine, the electric flat conveyor, the first elevator, the chain conveyor and the second elevator through industrial Ethernet, so that the full-automatic process of stacking the zinc sheet and automatically transporting the zinc stack to the target area is controlled. First, the zinc sheet is counted and stacked through the zinc sheet stacking machine, and the layer thickness standard signal is obtained when the layer thickness of the zinc sheet reaches the set value. According to the layer thickness standard signal, it is known that the zinc sheet has become a zinc stack, the zinc stack is moved through the zinc stack conveying line, and the arrival signal is obtained after reaching the target point. According to the sequence of the arrival signal, the zinc stack is transferred to the electric flat conveyor and moved to the first elevator, and the zinc stack is lifted to the chain conveyor through the first elevator, and the zinc stack is conveyed to the specified position through the chain conveyor, and then the second elevator drives the zinc stack to descend to the target area to complete the transportation of the zinc stack.

[0030] In some embodiments, the zinc stack automatic transportation device adopts decentralized and centralized control. Preferably, it is composed of one set of S7-1500 PLC master station, three sets of distributed I / O module slave stations, four sets of touch screens and multiple frequency converters. The frequency converter control adopts PN communication. It can be controlled locally or centrally in the control room. When the centralized control is automatically operated, the field emergency stop and pause are only effective locally and do not affect the global automatic operation. The industrial computer is installed in the control room to monitor and operate the whole system.

[0031] In some embodiments, in steps S100 to S300, specifically, a field touch screen control operation box AX1 is installed at the zinc sheet stacker position. The control operation box controls the zinc sheet stacker, the zinc stack conveying line, and the electric flat conveying machine. A set of S7-1500 PLC master station is arranged in the operation box. The touch screen is mainly used for system monitoring and manual operation. The zinc sheet stacker is lowered and counted according to the incoming zinc sheets. When the thickness of the zinc sheet layer reaches the set value, the PLC controls the frequency converter of the zinc stack conveying line to start at a set frequency, and moves a zinc ingot position at a time. When the zinc stack is conveyed to the front end detection position of the zinc stack conveying line, a reaching signal is sent. The PLC control system judges the sequence of the signal and the original old zinc stack conveying line zinc stack reaching signal. The electric flat conveying machine moves to the front end of the zinc stack conveying line where the zinc stack reaches earliest, and the zinc stack is transferred to the electric flat conveying machine. The electric flat conveying machine translates and conveys the zinc stack to the rotary elevator, i.e., the first elevator.

[0032] In some embodiments, in steps S400 to S500, a field touch screen control operation box AX2 is installed at the planar position of the rotary elevator. The control operation box controls the rotary elevator and the chain conveyors, including the first chain conveyor, the second chain conveyor and the third chain conveyor. A set of distributed I / O S7-1500 modules are installed in the box. The touch screen is mainly used for system monitoring and operation when manually operated. When the zinc stack on the electric flat conveyor reaches the starting position of the rotary elevator, which is detected by the field photoelectric switch, the PLC controls the conveyor frequency converter of the rotary elevator to start, and the zinc stack is conveyed forward until the zinc stack reaches the stopping position, which is detected by the field photoelectric switch, and the conveyor frequency converter of the rotary elevator stops working; at the same time, the PLC sends a command to control the rotary frequency converter of the rotary elevator to start, and the zinc stack rotates until the zinc stack rotates to the stopping position, which is detected by the field proximity switch, and the rotation stops; the PLC controls the lifting frequency converter to start, and the zinc stack is lifted until the zinc stack reaches the stopping position, which is detected by the field proximity switch, and the lifting stops, and the conveyor of the rotary elevator starts to convey the zinc stack forward; whenever the zinc stack reaches the starting position of the first chain conveyor, which is detected by the field photoelectric switch, the PLC controls the first chain conveyor frequency converter to start, and the first chain conveyor frequency converter stops working after conveying one zinc stack position, and the field photoelectric switch detects the starting signal every time, and the PLC controls the conveyor to move one zinc stack position; whenever the zinc stack reaches the starting position of the second chain conveyor, which is detected by the field photoelectric switch, the PLC controls the second chain conveyor frequency converter to start, and the second chain conveyor frequency converter stops working after conveying one zinc stack position, and the field photoelectric switch detects the starting signal every time, and the PLC controls the conveyor to move one zinc stack position; whenever the zinc stack reaches the starting position of the third chain conveyor, which is detected by the field photoelectric switch, the PLC controls the third chain conveyor frequency converter to start, and the third chain conveyor frequency converter stops working after conveying one zinc stack position, and the field photoelectric switch detects the starting signal every time, and the PLC controls the conveyor to move one zinc stack position; photoelectric curtain switches are installed at the inlet and outlet positions of the upper end and lower end of the rotary elevator, and the switch signals are connected to the PLC as safety interlocking guarantee signals for zinc stack conveying, rotating and lifting actions.

[0033] A field touch screen control operation box AX3 is installed at the planar position of the second elevator. The operation box controls the fourth chain conveyor, the fifth chain conveyor, the second elevator and the sixth chain conveyor. A set of distributed I / O S7-1500 modules are installed in the box. The touch screen is mainly used for monitoring and manual operation. Whenever the field photoelectric switch detects that the zinc stack reaches the starting position of the fourth chain conveyor, the PLC controls the frequency converter of the fourth chain conveyor to start, and after conveying one zinc stack position, the frequency converter of the fourth chain conveyor stops working. The field photoelectric switch detects the starting signal every time, and the PLC controls the conveyor to move one zinc stack position. Whenever the field photoelectric switch detects that the zinc stack reaches the starting position of the fifth chain conveyor, the PLC controls the frequency converter of the fifth chain conveyor to start, and after conveying one zinc stack position, the frequency converter of the fifth chain conveyor stops working. The field photoelectric switch detects the starting signal every time, and the PLC controls the conveyor to move one zinc stack position. The field photoelectric switch detects the starting signal of the second elevator conveyor, and the PLC controls the conveying frequency converter of the second elevator conveyor to start, and the zinc stack conveying starts. The PLC controls the lifting frequency converter of the second elevator conveyor to start, and the zinc stack descends until the planar proximity switch detects the descending stop signal. The PLC controls the lifting frequency converter of the second elevator conveyor to stop working, and the zinc stack descending stops. The PLC controls the conveying frequency converter of the second elevator conveyor to start, and the zinc stack is conveyed forward. Whenever the field photoelectric switch detects that the zinc stack reaches the starting position of the sixth chain conveyor, the PLC controls the frequency converter of the sixth chain conveyor to start, and after conveying one zinc stack position, the frequency converter of the sixth chain conveyor stops working. The field photoelectric switch detects the starting signal every time, and the PLC controls the conveyor to move one zinc stack position, forming a photoelectric switch that detects that the zinc stack reaches the front end of the sixth chain conveyor. The PLC sends a communication signal to the furnace charging system to control the charging.

[0034] A field touch screen operation box AX4 is arranged at the planar position of the second lifting machine, which controls the seventh chain conveyor. A set of distributed I / O S7-1500 modules are installed in the box. The touch screen is mainly used for system monitoring and manual operation. The operation box is provided with a conveying line open circuit selection switch. When the PLC detects the conveying line open circuit selection signal, the sixth chain conveyor stops working, and the second lifting machine stops the descending stop proximity switch signal is taken from the planar proximity switch signal. Whenever the field photoelectric switch detects that the zinc stack reaches the starting position of the seventh chain conveyor, the PLC controls the seventh chain conveyor frequency converter to start, and conveys a zinc stack position. The seventh chain conveyor frequency converter stops working. The field photoelectric switch detects the starting signal every time, and the PLC controls the conveyor to move a zinc stack position. When the zinc stack reaches the front end of the seventh chain conveyor, the PLC controls the lifting device to rise. When the ingot field proximity switch detects the rising stop signal, the PLC controls the lifting device to stop rising, and waits for the forklift to manually unload the zinc stack. The light curtain switch is installed at the forklift unloading position, and these switch signals are used as safety interlocking guarantee signals for zinc stack conveying and forklift access.

[0035] More specifically, the first chain conveyor, the second chain conveyor and the third chain conveyor belong to the same conveying section in a progressive relationship. After the zinc stack is output from the first lifting machine, i.e. the rotary lifting machine, it is sequentially transmitted forward through the three conveyors, and each conveyor is only responsible for moving the zinc stack by one zinc stack position and then transmitting it to the next one, forming a segmented relay. The fourth chain conveyor and the fifth chain conveyor continue to convey the zinc stack from the third chain conveyor forward to the second lifting machine, which is a transition unit connecting the rotary lifting machine and the second lifting machine. The sixth chain conveyor receives the zinc stack conveyed by the second lifting machine and transmits it forward to the front end, and then triggers the furnace front feeding system or guides the zinc stack to the seventh chain conveyor when the seventh chain conveyor starts. The seventh chain conveyor is the unloading terminal, which forms selective connection with the sixth chain conveyor through the open circuit switch of AX4, and is specially responsible for conveying the zinc stack to the lifting position to wait for the forklift to carry away.

[0036] After the rotary elevator completes the rotation and lifting of the zinc stack, the conveyor of the rotary elevator forwards the zinc stack. When the photoelectric switch detects that the zinc stack reaches the starting position of the first chain conveyor, the PLC controls the frequency converter of the chain conveyor to start, and stops after conveying one zinc stack. Then the zinc stack triggers the photoelectric switch of the second chain conveyor, and the second chain conveyor moves in the same way, and then is transmitted to the third chain conveyor to complete the first-stage chain conveying. After the zinc stack is conveyed by the third chain conveyor, it enters the fourth chain conveyor and the fifth chain conveyor in turn, and the two are relayed according to the logic of photoelectric switch triggering-moving one zinc stack-stop, and finally the zinc stack is sent to the second lifting machine entrance. After the second lifting machine receives the zinc stack, it is sent into the equipment through the conveying frequency converter, and then the lifting frequency converter is started to make it descend to the plane, and then continues to be forwarded to the sixth chain conveyor; the sixth chain conveyor is started after detecting the zinc stack, and moves one zinc stack to the front end. When the conveying line open circuit selection switch of the AX4 operation box is triggered, the PLC controls the sixth chain conveyor to stop working, and the zinc stack is diverted into the seventh chain conveyor; the seventh chain conveyor is started after detecting the zinc stack through the photoelectric switch, and conveys one zinc stack to the front end, and finally triggers the lifting equipment to rise, and waits for the forklift to be offline.

[0037] Therefore, it can be understood that the automatic connection between devices is realized through sensor signals and PLC logic control. After the zinc sheet stacking machine automatically counts and stacks, the zinc stack is transferred in sequence by the zinc stack conveying line, the electric flat conveyor and other devices, which reduces the delay caused by manual intervention, makes the zinc stack transportation continuous and efficient, and at the same time, the priority judgment mechanism of the new and old zinc stack conveying line enables the electric flat conveyor to accurately dock the earliest arrived zinc stack, avoiding device idling and zinc stack accumulation, and greatly improving the transportation rhythm. In terms of operation convenience, the touch screen of each operation box can realize system monitoring and manual operation, so that workers can not only master the running state of the equipment in real time, but also quickly intervene and adjust when needed, and the efficiency of automatic production and the flexibility of manual operation are taken into account. In terms of safety, the light curtain switch installed in the key areas such as the first lifting machine, the second lifting machine and the forklift offline position forms a safety interlock with the PLC. Once it detects that a person or a foreign object intrudes, it immediately stops the related device action, effectively reducing the risk of safety accidents. In addition, in the decentralized control mode, local emergency stop and pause only affect specific devices and do not interfere with global automatic operation, which guarantees the continuity of production, provides reliable support for zinc ingot annual capacity, reduces the loss of production capacity caused by equipment failure or operation error, and improves the stability and economy of the overall production.

[0038] In some embodiments, during the automated transportation of zinc stacks, photoelectric switches and auxiliary sensors are used to accurately detect whether the zinc stacks have reached the starting position of each device. The photoelectric switch serves as the main detection device, and is used in conjunction with auxiliary sensors such as ultrasonic sensors, laser sensors, or infrared sensors to detect the position of the zinc stacks. The system sets a specific time window, such as 300 ms, and when the detection signals output by the photoelectric switch and the selected auxiliary sensor remain consistent within this time window, the PLC confirms that the zinc stack has accurately reached the starting position of the corresponding device, triggering subsequent device actions (such as the start of the conveyor line, the operation of the elevator, etc.). This dual detection mechanism can effectively avoid false judgments caused by single sensors being disturbed by environmental factors such as zinc dust and water vapor, greatly improving the accuracy and reliability of zinc stack position detection, and providing a key guarantee for the smooth operation of the entire transportation process. It can be understood that dual sensors are deployed at key detection positions, including the end of the conveyor line, the rotation stop position, and the interface of the series conveyor.

[0039] In some embodiments, during the automated transportation of zinc stacks, the zinc sheet stacking machine, the electric flat conveyor, the first elevator, the chain conveyor, and the second elevator are all connected to the corresponding PLC using two independent industrial Ethernet cables, forming a physical communication architecture of main link + backup link. This dual-link design ensures the redundancy of data transmission between the devices and the PLC, and when one of the links fails (such as a broken line or interference), the other link can immediately take over the data transmission task, avoiding communication interruptions that could cause the devices to lose control. At the same time, redundant ring network technology is deployed at the network switch level, including MRP media redundancy protocol, which connects all participating switches into a ring network, further improving the reliability of the communication system. It can be understood that when a cable or switch in the ring network fails, the redundant ring network technology can automatically switch the communication path in a very short time, ensuring the continuity of the entire network communication, thereby ensuring the stable operation of the entire process of zinc sheet stacking, zinc stack transportation, lifting, and transfer, providing solid communication support for production efficiency and safety.

[0040] In some embodiments, in order to further ensure the safety and stability of the zinc pile transportation process, a safety light curtain, an overload sensor and a speed encoder are arranged in the transportation process and are respectively connected with the PLC in each control box. The safety light curtain realizes signal hard-wired safety interlocking through safety PLC technology, forms reliable safety protection at the inlet and outlet positions of the first and second elevators and the area below the forklift, and can immediately trigger equipment shutdown and eliminate safety hazards from the hardware level once detecting the intrusion of personnel or foreign objects; the overload sensor is specially installed at the motor of the zinc sheet stacking machine, the electric flat conveyor, the first elevator and the second elevator, and monitors the motor operating current in real time, and when the current exceeds the rated value, the signal is quickly transmitted to the PLC to avoid motor damage due to overload; the speed encoder is arranged on the drive shaft of all chain conveyors to accurately detect the chain running speed, and if the speed deviates from the set range threshold, an abnormal signal will be sent to the PLC immediately. Through the cooperative action of the overload sensor and the speed encoder, the PLC can master the motor load and chain transmission state of the equipment in real time, and combined with the protection function of the safety light curtain, a multi-level safety monitoring and interlocking system is formed to comprehensively improve the safety redundancy and operation reliability of the system.

[0041] In some embodiments, in the zinc pile transportation process, when the new zinc pile conveying line and the original old zinc pile conveying line both send signals that the zinc pile has reached the detection position at the front end of each conveying line, the S7-1500 PLC in the AX1 control box will play a core role. The PLC processes the two arrival signals through a numerical comparison algorithm, which considers factors such as the waiting time of the zinc pile on the new and old conveying lines, the current load of the conveying line, etc., and automatically calculates and determines the conveying line with higher priority. Then, the PLC sends a control instruction to the electric flat conveyor to move to the front end of the conveying line with higher priority, complete accurate docking with the conveying line, and then transfer the corresponding zinc pile to the electric flat conveyor and then to the first elevator. Such control logic ensures that the zinc pile can be transferred in the optimal order, avoids conveying line congestion, and improves overall transportation efficiency.

[0042] In some embodiments, the PLC control program reads the status register of the frequency converter in real time through industrial Ethernet communication, continuously collects sensor signals and calculates their jump frequency, and judges the running state of the equipment through real-time monitoring of the two types of data; once a fault is detected, the control program uses fault code mapping technology to convert the abnormal code fed back by the frequency converter status register and the abnormal jump of the sensor signal into a specific fault description. For example: the second chain conveyor frequency converter overload, the first elevator photoelectric switch signal instability, etc., and sends these specific fault descriptions containing fault location, cause and maintenance guidance suggestions to the touch screen and other visual displays, so that the operator can intuitively and quickly understand the fault situation, so as to take targeted measures for processing in time, effectively shorten the fault troubleshooting and solving time, and ensure the continuity of zinc pile transportation.

[0043] Specifically, in the process of automatic transportation control of zinc piles, once a fault is detected, the control program will start the fault code mapping mechanism. First, the status register of each device frequency converter is read in real time through PN communication, such as the frequency converter of the zinc pile conveying line and the first elevator, and the abnormal code fed back therein is extracted, such as overload code, overvoltage code or communication interruption code; At the same time, the signal waveform of each photoelectric switch, proximity switch and other sensors is continuously monitored to capture the abnormal jump of the signal, such as frequent on-off in a short time, signal loss or continuous high / low level. The control program has a mapping table preset therein, which associates these abstract code values and signal characteristics with specific equipment fault types, such as first chain conveyor frequency converter overload, first elevator proximity switch disconnection, seventh chain conveyor photoelectric switch signal interference, etc. Abstract data is converted into intuitive text description through logical operation, and is displayed in real time on the touch screen of the corresponding operation box, such as the AX2 touch screen displaying the second chain conveyor frequency converter overvoltage, accompanied by fault location, possible cause and preliminary processing suggestion, so that the operator can quickly locate the problem, shorten the fault troubleshooting and processing time, and ensure the continuity of production.

[0044] In some embodiments, during the automatic transportation control process of the zinc pile, the production capacity balancing algorithm tracks the changes in the number of zinc piles at each key node in real time, including the first elevator inlet, the chain conveyor connection, etc., continuously monitors the stacking state, and accurately predicts the congestion risk that may occur in the future by comparing the processing capacity of each device with the actual transfer rhythm, including the conveyor conveying speed and the lifting efficiency of the elevator, etc. Once it is found that a certain area may cause process stagnation due to zinc pile accumulation, dispatching instructions are immediately sent to the main station PLC and related distributed I / O modules, such as adjusting the speed of the electric flat conveyor or optimizing the start-stop interval of each chain conveyor, to dynamically balance the production capacity of each link; at the same time, the zinc pile transfer amount recorded by the photoelectric switch at the end of all conveying lines is counted every fixed unit period (such as every hour), and the cumulative production capacity is accumulated to calculate the deviation rate compared with the target value of annual production capacity. If the actual production capacity of multiple target periods is lower than the preset threshold, a multi-level early warning mechanism is triggered. The first level of warning is pushed to the on-site operation box touch screen to prompt the operator to adjust, the second level of warning is sent to the control room industrial computer to display the bottleneck device position, and the third level of warning is notified to the management personnel through SMS. In addition, based on historical operation data such as device energy consumption or transfer efficiency under different zinc pile weights, the device core parameters including the frequency converter operating frequency, sensor detection threshold, and elevator action interval, etc. are iteratively optimized by genetic algorithm, and the optimized parameters are pushed to the operator interface. After confirmation, the production parameters are automatically updated to the control program of the corresponding device by PLC through PN communication, realizing intelligent adaptation of production parameters and continuously improving transportation efficiency and production capacity stability under the premise of safety. Please refer to Figure 2 The embodiments of the present application also provide a PLC control system for automatic transportation of zinc piles, which can implement the above method. The system comprises: A layer thickness confirmation module is configured to control the motor of the zinc sheet stacking machine through industrial Ethernet communication to obtain a layer thickness standard signal. A reaching signal generation module is configured to trigger the frequency converter of the zinc pile conveying line according to the layer thickness standard signal, move the zinc pile through the zinc pile conveying line, and obtain a reaching signal. A flat conveying module is configured to transfer the zinc pile to the electric flat conveyor according to the sequence of the reaching signals, and move the zinc pile to the first elevator through the electric flat conveyor. A first lifting module is configured to control the first elevator to lift the zinc pile to the start position of the chain conveyor through the sensor when the zinc pile is moved to the first elevator. A second lifting module is configured to convey the zinc pile to the second elevator through the chain conveyor, and the second elevator lowers the zinc pile to the target area to complete the transportation of the zinc pile.

[0045] It can be understood that the contents in the above method embodiments are applicable to the system embodiments, the system embodiments specifically implement the functions same as the above method embodiments, and achieve the beneficial effects same as the above method embodiments.

[0046] The application also provides a computer readable storage medium, which stores a computer program. The computer program is executed by a processor to implement the method described above.

[0047] It can be understood that the contents in the above method embodiments are applicable to the storage medium embodiments, the storage medium embodiments specifically implement the functions same as the above method embodiments, and achieve the beneficial effects same as the above method embodiments.

[0048] The embodiments described in the application are used to more clearly illustrate the technical solutions of the application, and do not constitute a limitation on the technical solutions provided by the application. Those skilled in the art can know that, with the evolution of technology and the appearance of new application scenarios, the technical solutions provided by the application are also applicable to similar technical problems.

[0049] Those skilled in the art can understand that the technical solutions shown in the figures do not constitute a limitation on the application, and can include more or fewer steps than the figures, or combine certain steps or different steps.

[0050] The device embodiments described above are only schematic, and the units described as separate components can or can not be physically separate, that is, can be located in one place, or can be distributed on multiple network units. Part or all of the modules can be selected according to actual needs to achieve the purpose of the embodiments.

[0051] Those skilled in the art can understand that all or some steps in the above disclosed method, the functions of the modules / units in the system and the device can be implemented as software, firmware, hardware and their appropriate combinations.

[0052] It should be understood that the data used in this way can be interchanged under appropriate circumstances, so that the embodiments of the application described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device including a series of steps or units does not have to be limited to those steps or units clearly listed, but can include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0053] It should be understood that, in the present application, "at least one" refers to one or more, and "multiple" refers to two or more. "And / or" is used to describe the association relationship of the associated objects, which means that there can be three relationships, for example, "A and / or B" can mean: only A, only B, and A and B exist at the same time, where A and B can be singular or plural. The character " / " generally represents an "or" relationship between the associated objects before and after it. "At least one of the following" or similar expressions means any combination of these items, including any combination of single or multiple items. For example, at least one of a, b or c, can mean: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, and c can be single or multiple.

[0054] In several embodiments provided in the present application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are only illustrative, for example, the division of the above units is only a logical function division, and actual implementation can have another division manner, for example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the coupling or direct coupling or communication connection between the displayed or discussed each other can be indirect coupling or communication connection through some interfaces, devices or units, which can be electrical, mechanical or other forms.

[0055] The units described above as separate components can or can not be physically separated, and the components shown as units can or can not be physical units, that is, they can be located in one place, or they can be distributed on multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the embodiment of the present application.

[0056] In addition, the functional units in each embodiment of the present application can be integrated in one processing unit, or each unit can exist physically, or two or more units can be integrated in one unit. The integrated unit can be realized in the form of hardware or in the form of a software functional unit.

[0057] The preferred embodiments of the embodiments of the present application are described above with reference to the accompanying drawings, which do not limit the scope of the embodiments of the present application. Any modifications, equivalent replacements and improvements made by those skilled in the art without departing from the scope and essence of the embodiments of the present application shall be within the scope of the embodiments of the present application.

Claims

1. A PLC control method for automated transportation of zinc stacks, characterized in that, The method includes the following steps: The motor of the zinc sheet palletizer is controlled via industrial Ethernet communication to obtain a signal indicating that the layer thickness meets the standard. The frequency converter of the zinc stack conveyor line is triggered according to the layer thickness compliance signal, and the zinc stack is moved through the zinc stack conveyor line to obtain the arrival signal; The zinc stack is transferred to the electric flatbed conveyor according to the order of arrival signals, and then the electric flatbed conveyor moves the zinc stack to the first elevator. When the sensor detects that the zinc stack has been moved to the first elevator, the first elevator is controlled to lift the zinc stack to the starting position of the chain conveyor. The zinc stack is transported to the second elevator via the chain conveyor. The second elevator then lowers the zinc stack to the target area, completing the transport of the zinc stack.

2. The method according to claim 1, characterized in that, The sensor detection includes photoelectric switch detection and proximity switch detection; The photoelectric switch is used to detect whether the zinc stack has reached the start position of each device. The proximity switch is used to detect whether the operation of each device has reached the stop position.

3. The method according to claim 2, characterized in that, The photoelectric switch and the auxiliary sensor simultaneously detect whether the zinc stack has reached the start position of each device. When the photoelectric switch and the auxiliary sensor are consistent within a set time window, it is confirmed that the zinc stack has reached the start-up position of each device. The auxiliary sensors include ultrasonic sensors, laser sensors, or infrared sensors.

4. The method according to claim 1, characterized in that, The zinc sheet palletizer, the electric flatbed conveyor, the first elevator, the chain conveyor, and the second elevator communicate with the PLC via two independent industrial Ethernet cables. Redundant ring network technology is deployed at the network switch level using two industrial Ethernet cables.

5. The method according to claim 1, characterized in that, It also includes a safety light curtain, overload sensors, and a speed encoder; The safety light curtain, the overload sensor, and the speed encoder are respectively connected to the PLC for communication. The safety light curtain uses safety PLC technology to achieve hard-wired safety interlocking of signals; The overload sensor is installed at the motor of the zinc sheet palletizer, the electric flat conveyor, the first elevator, and the second elevator; The speed encoder is located at the drive shaft of the chain conveyor; The overload sensor and the speed encoder are used to monitor motor overload and detect abnormal chain speed.

6. The method according to claim 1, characterized in that, The step of transferring the zinc stack to the electric flatbed conveyor according to the order of arrival signals includes: When both the old and new lines send the arrival signal, the PLC automatically selects the higher priority conveyor line based on the arrival signal using a numerical comparison algorithm, and controls the electric flat conveyor to connect first.

7. The method according to claim 1, characterized in that, The PLC control program obtains the inverter status register in real time through the industrial Ethernet communication. Obtain the switching frequency of the sensor signal; Real-time detection of the switching frequency of the inverter status register and the sensor signal; When a fault is detected, the abnormal state is converted into a specific fault description through fault code mapping technology; The specific fault description is sent to a visual display to show the fault location, cause, and guidance suggestions.

8. The method according to claim 1, characterized in that, It also includes the following steps: The stacking status of the zinc stack is monitored in real time by a capacity balancing algorithm. Based on the stacking status, the congestion risk is predicted and a scheduling command is sent to the PLC. The system counts the transfer volume of the zinc stack per unit period and calculates the deviation rate between the cumulative production capacity and the target production capacity. When the target period is lower than the preset threshold, a multi-level warning is triggered and pushed to the corresponding terminal. Based on historical data, the equipment operating parameters are optimized using a genetic algorithm. After the optimized operating parameters are sent to the operator for confirmation, the parameters are automatically updated via the PLC.

9. A PLC control system for automated transport of zinc stacks, characterized in that, The system includes: The layer thickness confirmation module is used to control the motor of the zinc sheet palletizer via industrial Ethernet communication to obtain a layer thickness compliance signal. The arrival signal generation module is used to trigger the frequency converter of the zinc stack conveyor line according to the layer thickness compliance signal, and move the zinc stack through the zinc stack conveyor line to obtain the arrival signal; A flatbed conveyor module is used to transfer the zinc stack to an electric flatbed conveyor according to the order of arrival signals, and then move the zinc stack to the first elevator via the electric flatbed conveyor. The first lifting module is used to control the first lifting machine to lift the zinc stack to the chain conveyor start position when the stack is moved to the first lifting machine by a sensor. The second lifting module is used to transport the zinc stack to the second elevator via the chain conveyor. The second elevator drives the zinc stack to descend to the target area to complete the transportation of the zinc stack.

10. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by a processor, it implements the method of any one of claims 1 to 8.

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