Fool-proof system of electric welding machine based on feed production

Abstract

The invention relates to the technical field of safety control, and discloses an electric welding machine fool-proof system based on feed production, which comprises an electric welding machine main body unit, and an intelligent control terminal and a mobile interaction terminal which are connected in series in a power supply loop of the electric welding machine main body unit, the intelligent control terminal is integrated with a micro-control unit, a power on-off unit and a wireless communication unit. The mobile interaction terminal is configured to collect an operation certificate image, and after OCR recognition and compliance judgment pass, an encrypted data packet containing a control instruction is generated; the micro-control unit receives and verifies the time validity and integrity of the data packet, and drives the normally-open power on-off unit to be closed according to a verification result, so that the electric welding machine power supply is switched on; in addition, the system has the functions of heartbeat monitoring, operation duration limiting and environment safety linkage, and forced resetting and power failure are achieved in the abnormal state. According to the invention, through forced linkage of physical blocking and qualification checking, illegal operation without a certificate is avoided, and the fire operation safety level of a feed production environment is improved.

Description

Technical Field

[0001] This invention relates to the field of safety control technology, and in particular to a foolproof system for welding machines based on feed production. Background Technology

[0002] Electric welding machines, as industrial equipment that uses electrical energy converted into heat energy to weld metal, are widely used in equipment maintenance, pipeline installation, and infrastructure construction in feed production enterprises. However, existing electric welding machines are designed to be directly connected to the power grid, and their power supply circuits lack mandatory identification and qualification verification mechanisms. While this plug-and-play open operating logic simplifies the operation process, it also allows personnel without special operation certificates to start and operate this type of high-risk equipment at will. In the absence of effective supervision, unauthorized hot work operations can easily lead to serious safety accidents such as short circuits, electric shocks, and fires caused by sparks.

[0003] Furthermore, traditional welding machine safety management relies on manual on-site inspections, lacking digital monitoring methods for the operation process. Once the equipment is powered on and started, it remains in a continuous standby state, lacking automatic monitoring functions for operation duration or operator presence. If the operator leaves midway or becomes fatigued, the equipment will remain unattended for extended periods, creating safety hazards. Simultaneously, existing simple control schemes lack robust communication security mechanisms, making control commands susceptible to forgery or replay, leading to unauthorized activation of the equipment and failing to guarantee the uniqueness and legitimacy of control signals.

[0004] Especially in the specific application scenario of feed production, the working environment is often accompanied by high concentrations of dust or potentially flammable gases, making it a typical explosion-proof key area. Conventional welding machines lack environmental sensing capabilities and cannot automatically adjust their power supply strategy based on the on-site dust or gas concentration. Moreover, existing high-power feed processing equipment has a complex structure, and upgrading it for intelligent safety requires disrupting the original circuit structure, which is difficult and costly, making it difficult to achieve low-cost, highly reliable error-proof upgrades without affecting the performance of the original equipment. Therefore, there is an urgent need for a welding machine safety control system that can achieve physical blocking, intelligent authentication, process monitoring, and environmental linkage. Summary of the Invention

[0005] The purpose of this invention is to provide a foolproof system for welding machines based on feed production, which solves the problems of existing welding machine equipment lacking a mandatory identity and qualification lock-in mechanism, leading to unlicensed personnel operating illegally, and lacking linkage monitoring of operation time, communication security and environmental indicators in the complex environment of feed production, thus posing serious safety hazards.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] This invention provides a foolproof system for welding machines used in feed production, comprising a main welding machine unit, an intelligent control terminal, and a mobile interactive terminal. The main welding machine unit, acting as a load device, includes a power input interface for receiving AC power and a welding circuit. The intelligent control terminal is connected in series and fixedly connected to the power supply circuit of the main welding machine unit. In a specific implementation, the front-end physical circuit of the power input interface is interrupted, and the intelligent control terminal is connected in series at the interruption point. The intelligent control terminal integrates a microcontroller unit, a power on / off unit, a first wireless communication unit, and an auxiliary power supply unit. The mobile interactive terminal establishes a wireless data communication link with the intelligent control terminal and is responsible for front-end information collection and interaction.

[0008] In terms of control logic, the mobile interactive terminal is configured to collect image information of special operation certificates and verify operational qualifications. Only after successful verification does the mobile interactive terminal generate a data packet containing control commands and send it to the intelligent control terminal. The first wireless communication unit receives the data packet and transmits it to the microcontroller unit. The microcontroller unit verifies the data packet and controls the operation of the power on / off unit based on the verification result. The power on / off unit is connected in series between the external power grid and the power input interface. It is used to execute the closing or opening action of physical contacts according to the drive signal, thereby directly controlling the power supply status of the main unit of the welding machine and realizing foolproof control of no power supply without a certificate.

[0009] Furthermore, to ensure the system's standby and control capabilities during power outages, the power switching unit employs normally open relays or AC contactors, with its control coil circuit electrically isolated from the main contact circuit. When no drive signal is input, a mechanical return spring forces the contacts to remain open, physically blocking power transmission. The auxiliary power supply unit uses a front-end power draw method; its input is connected in parallel to the front end of the power switching unit and directly to the external power grid, while its output powers the microcontroller unit and the first wireless communication unit. This circuit topology ensures that even when the main circuit of the welding machine is disconnected, the control core and communication module of the intelligent control terminal remain energized and ready to respond to valid closing commands.

[0010] In terms of qualification verification and data processing, the mobile interactive terminal uses a data processing unit to execute an optical character recognition algorithm, converting the collected document images into a user feature dataset containing characteristic elements such as name, ID number, job category, and certificate expiration date. The system has built-in compliance judgment logic to verify whether the job category belongs to the license set and whether the certificate is valid. Only when both conditions are met simultaneously does the system recognize the verification status as valid and generate a digital access token.

[0011] To ensure the security and immutability of the communication process, the system employs encryption and handshake mechanisms. The mobile interactive terminal obtains the unique device identifier, digital access token, and current system timestamp from the intelligent control terminal. Using a secure hash algorithm, it concatenates this data in a predetermined order to generate an encrypted verification code, and encapsulates the plaintext timestamp and ciphertext verification code in a data frame for transmission. The microcontroller unit of the intelligent control terminal executes strict terminal verification logic: on one hand, it performs a time validity check, calculating whether the difference between the local clock and the received timestamp is within the allowable delay threshold to prevent replay attacks; on the other hand, it performs a data integrity check, recalculating the hash value using the locally stored device identifier, current session token, and received timestamp, and comparing it with the received encrypted verification code. Only when both time validity and data integrity are verified does the microcontroller unit output a high-level drive signal, controlling the power on / off unit to close via the isolation drive circuit.

[0012] To address the specific safety requirements of feed production environments, this invention also integrates a dynamic status monitoring mechanism. The microcontroller internally runs a heartbeat communication monitoring module and an operation duration monitoring module concurrently. The heartbeat communication monitoring module detects the real-time status of the communication link to prevent the equipment from remaining powered on even after the control unit has gone offline; the operation duration monitoring module limits the maximum duration of continuous operation in a single session to prevent fatigue-related work or prolonged unattended operation. If a heartbeat timeout or operation duration exceedance occurs, the system determines it to be a fault state and forcibly stops outputting drive signals and disconnects the power on / off unit via logic gate circuits.

[0013] Furthermore, this invention provides extended solutions for different application scenarios. For high-power feed equipment, the power switching unit of the intelligent control terminal can be connected in series in the control coil circuit of an external three-phase AC contactor to achieve a two-level control architecture of small current controlling large current. In terms of communication methods, in addition to conventional wireless communication, power line carrier communication technology can also be used. This utilizes existing power frequency AC lines to transmit data frames containing network identifiers, timestamps, and encrypted verification codes, and ensures the validity of the signal within a specific power grid area through network attribution logic. Simultaneously, to address the risks of high dust or flammable gas in feed workshops, the system can be connected to environmental monitoring sensors to read the concentration of flammable gas or dust in real time. When the environmental concentration reaches a preset safety threshold, the environmental safety status variable will directly block the control signal and forcibly disconnect the circuit, thereby achieving comprehensive foolproof protection from personnel qualification compliance to environmental safety.

[0014] Through the above technical solution, this invention constructs a safety control system for electric welding machines that integrates physical blocking, intelligent authentication, encrypted communication, and environmental linkage, solving the problems of unlicensed operation and illegal use of electricity, and improving the safety management level of hot work operations in feed production enterprises.

[0015] In summary, the present invention has at least one of the following beneficial technical effects:

[0016] 1. This invention connects an intelligent control terminal in series in the power supply circuit of the welding machine. It uses normally open power switching units (such as relays or contactors) to maintain a physical open circuit under normal conditions, blocking the transmission of electrical energy. Only when the mobile interactive terminal collects the image of the special operation certificate and verifies the qualification compliance (such as matching the job type and not being expired) through the OCR algorithm will a command closed circuit be generated. This changes the traditional situation of welding machines being plugged in and used immediately, and solves the problem of fire or electric shock accidents caused by unlicensed personnel operating the equipment in high-risk places such as feed mills.

[0017] 2. This invention employs a hash-encrypted handshake protocol based on a unique device identifier, digital token, and timestamp, and sets a maximum latency threshold to prevent forgery and replay attacks of control commands. Simultaneously, the microcontroller internally runs heartbeat communication monitoring and operation duration monitoring logic concurrently. Once a communication link interruption or single operation time exceeding the limit is detected, the system automatically triggers a fault reset mechanism to force a power outage, thereby ensuring the legitimacy of control signals and mitigating secondary risks caused by personnel leaving the equipment unattended for extended periods.

[0018] 3. The intelligent control terminal of this invention adopts an auxiliary power supply design with front-end parallel power supply, which can be installed at low cost without damaging the internal structure of the welding machine, and supports high-power three-phase equipment control through two-stage drive; in addition, the system reserves an environmental safety logic interface, which can be linked to dust or combustible gas sensors in the feed workshop; when the environmental concentration exceeds the safety threshold, the control signal is directly blocked, thereby improving the applicability and comprehensive safety protection level of the system in specific scenarios of feed production with high dust and flammable and explosive conditions. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of the welding machine error prevention system based on feed production provided in an embodiment of the present invention;

[0020] Figure 2 This is a flowchart of the identity authentication and instruction generation process for a mobile interactive terminal provided in an embodiment of the present invention;

[0021] Figure 3 This is a flowchart illustrating the data verification and drive execution process of an intelligent control terminal provided in an embodiment of the present invention.

[0022] Figure 4 A flowchart illustrating the operation status monitoring and safety reset process of an intelligent control terminal provided in this embodiment of the invention.

[0023] Among them, 100 is the main body unit of the welding machine; 110 is the power input interface; 120 is the welding circuit; 200 is the intelligent control terminal; 210 is the microcontroller unit; 220 is the power switching unit; 230 is the first wireless communication unit; 240 is the auxiliary power supply unit; 300 is the mobile interactive terminal; 310 is the image acquisition unit; 320 is the data processing unit; and 330 is the second wireless communication unit. Detailed Implementation

[0024] The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] See attached document Figure 1 This invention provides a foolproof system for welding machines used in feed production. The system includes a welding machine main unit 100, an intelligent control terminal 200, and a mobile interactive terminal 300. The welding machine main unit 100 is a welding execution device used for the maintenance of feed production equipment. The intelligent control terminal 200 is physically connected to the power supply path of the welding machine main unit 100. The mobile interactive terminal 300 establishes a connection with the intelligent control terminal 200 through a wireless communication protocol.

[0026] The main unit 100 of the welding machine includes a power input interface 110 and a welding circuit 120. The power input interface 110 is used to receive AC power. The welding circuit 120 is electrically connected to the power input interface 110 and is used to convert the input AC power into low-voltage, high-current power required for welding. In the normal state without the intelligent control terminal 200, the power input interface 110 is directly connected to the industrial power grid. In this embodiment, the front-end physical circuit of the power input interface 110 is cut off, and the intelligent control terminal 200 is connected in series.

[0027] The intelligent control terminal 200 includes a housing and a microcontroller unit 210, a power on / off unit 220, a first wireless communication unit 230, and an auxiliary power supply unit 240 encapsulated within the housing. Considering the dust accumulation and flammability issues in feed production workshops, the housing adopts a sealed structure meeting IP54 or higher protection standards. An optical identification tag is provided on the outer surface of the intelligent control terminal 200, containing the intelligent control terminal 200's unique device identifier and communication address information.

[0028] The power switching unit 220 is connected in series between the external power grid live wire and the power input interface 110. The power switching unit 220 is a normally open relay or AC contactor. The control terminal of the power switching unit 220 is electrically connected to the general-purpose input / output interface of the microcontroller unit 210.

[0029] Define the input voltage provided by the external power grid as The load voltage received by the power input interface 110 is The physical contact state of the power switching unit 220 is as follows: .in, ,when When the contact is open, it indicates that the contact is open. The time indicates that the contact is closed. The power supply state of the main unit 100 of the welding machine satisfies the following voltage transmission formula:

[0030] ;

[0031] The input terminal of the auxiliary power supply unit 240 is connected in parallel to the front end of the power switching unit 220, i.e., directly connected to the external power grid. The auxiliary power supply unit 240 converts the high-voltage AC power from the external power grid into low-voltage DC power. The output terminal of the auxiliary power supply unit 240 is electrically connected to the power supply terminals of the microcontroller unit 210 and the first wireless communication unit 230, respectively. This connection method ensures that when the power switching unit 220 is in the off state (i.e., when the power switching unit 220 is in the off state...), the power supply unit 240 is connected in parallel to the front end of the power switching unit 220, i.e., ... When the microcontroller unit 210 and the first wireless communication unit 230 are in a powered-on state, they remain powered on.

[0032] The microcontroller unit 210 is the logic processing center of the intelligent control terminal 200, used to receive data from the first wireless communication unit 230 and send drive signals to the power on / off unit 220. The first wireless communication unit 230 is configured as a Bluetooth communication module or a Wi-Fi communication module, used to perform data demodulation and transmission.

[0033] The mobile interactive terminal 300 is a portable electronic device with computing and image acquisition capabilities. The mobile interactive terminal 300 includes an image acquisition unit 310, a data processing unit 320, and a second wireless communication unit 330. The image acquisition unit 310 is configured as a camera for acquiring image information of special operation certificates and optical character recognition tags. The data processing unit 320 is connected to the image acquisition unit 310 and is used to perform optical character recognition and encryption operations. The second wireless communication unit 330 is connected to the data processing unit 320 and is used to establish a data link with the first wireless communication unit 330.

[0034] This embodiment describes in detail the connection method and device configuration of the power supply on / off control circuit inside the intelligent control terminal 200.

[0035] The power supply on / off control circuit is located between the external power grid power supply terminal and the power input interface 110. The power on / off unit 220 is configured as the physical cut-off actuator of the circuit, and its specific implementation is adapted according to the rated power and number of input phases of the welding machine main unit 100.

[0036] In single-phase AC power supply applications, the power switching unit 220 uses a double-pole normally open power relay. The phase line (L) and neutral line (N) of the external power grid are respectively connected to the two stationary contact input terminals of the power relay, and the two moving contact output terminals of the power relay are respectively connected to the corresponding terminals of the power input interface 110. This double-wire disconnection structure ensures that the welding machine main unit 100 is completely isolated from the power grid when the circuit is disconnected, eliminating the safety hazards caused by reverse connection of live and neutral wires that may occur with single-wire disconnection.

[0037] In applications requiring three-phase AC power (such as high-power welding machines used for feed pellet mill maintenance), the power switching unit 220 uses a three-pole normally open AC contactor. The three live wires (L1, L2, L3) of the external power grid are connected to the three main contact input terminals of the AC contactor, and the three main contact output terminals of the AC contactor are connected to the power input interface 110. The AC contactor is internally equipped with arc-extinguishing grids to extinguish the arc at the moment of contact disconnection, preventing external sparks from being generated in the dusty environment of the feed mill.

[0038] The power switching unit 220 serves not only as a switching device but also as a physical foolproof layer. Its control coil circuit is electrically isolated from the main contact circuit. In the default state without a drive signal input, the power switching unit 220 is forcibly held in the off position by the mechanical return spring (i.e., The electromagnetic force overcomes the spring resistance and closes the contacts only when the control coil receives a continuous sustaining voltage (i.e., the state of the control coil). Power can only be transmitted when the device is in a safe, power-off state. This normally open logic ensures that the device always returns to a safe, power-off state in the event of system failure, power outage of the control terminal, or human-caused damage to the control circuit.

[0039] This embodiment describes in detail the specific circuit structure and logic process of the microcontroller unit 210 generating control signals and driving the power switching unit 220 to operate.

[0040] The microcontroller unit 210 is equipped with specific general purpose input / output (GPIO) ports for outputting digital control signals. An isolation drive circuit module is provided between the microcontroller unit 210 and the power on / off unit 220. The isolation drive circuit module includes an optocoupler, a switching transistor, and a freewheeling diode. The anode of the optocoupler's input side is connected to the GPIO port of the microcontroller unit 210 through a current-limiting resistor, and the cathode of the input side is connected to logic ground. The collector of the optocoupler's output side is connected to the positive terminal of the drive power supply, and the emitter is connected to the base (or gate) of the switching transistor.

[0041] The microcontroller unit 210 has a logic operation program running inside it, which is used to generate control signal states in real time. Define the authentication verification result variable as follows: ,in This indicates that authentication has been successful. This indicates that verification failed or was not verified. Define the system fault monitoring variable as... ,in This indicates that a communication failure or hardware malfunction has been detected. This indicates that the system is functioning normally. Control signal status. Follow the following Boolean logic operation formula:

[0042] ;

[0043] in, This variable represents the authentication and verification result. Indicates system fault monitoring variables; This represents the logical AND operator. This represents the logical NOT operator.

[0044] When the control signal status Logically true (i.e.) When the signal is high, the microcontroller unit 210 controls the GPIO port to output a high level. This high-level signal drives the LED inside the optocoupler to conduct and emit light, thereby triggering the output-side phototransistor to conduct. The conducting phototransistor injects drive current into the control electrode of the switching transistor, causing the switching transistor to be in a saturated conduction state.

[0045] The collector (or drain) of the switching transistor is connected to one end of the control coil of the power switching unit 220, and the other end of the control coil is connected to the coil power supply. When the switching transistor is turned on, a potential difference is formed across the control coil, and the rated operating current flows through the coil, generating an electromagnetic attraction force to drive the contacts to close.

[0046] A freewheeling diode is connected in reverse parallel across the two ends of the control coil. When Become logically false (i.e.) When the switching transistor is turned off, the freewheeling diode provides a discharge path for the reverse induced electromotive force generated by the control coil, preventing high voltage from breaking down the switching transistor and ensuring the electrical stability of the drive circuit under frequent on-off operations.

[0047] This embodiment describes in detail the circuit implementation of how the intelligent control terminal 200 obtains the electrical energy required to maintain its own logic operation from the external power grid when the power switching unit 220 is in the off state.

[0048] The power sampling point of the auxiliary power supply unit 240 is physically connected before the input terminal of the power switching unit 220, that is, directly connected in parallel between the phase line and the neutral line of the external power grid (or between two phases of a three-phase power grid). This pre-powered structure establishes the working mode of the intelligent control terminal 200 as a standby device, making its power supply state independent of the on / off state of the main welding machine unit 100.

[0049] The auxiliary power supply unit 240 mainly consists of a wide-voltage input rectifier module, a flyback switching converter module, and a linear voltage regulator module. Given that the starting and stopping of high-power inductive loads such as pellet mills and grinders in feed production workshops often cause fluctuations in the mains voltage, a varistor and a transient voltage suppressor diode (TVS) are connected in series at the front end of the wide-voltage input rectifier module to absorb surge voltages and spike pulses from the mains, protecting subsequent circuits.

[0050] The wide-voltage input rectifier module converts the input industrial frequency alternating current (AC) into high-voltage direct current (DC). The flyback switching converter module steps down and isolates the high-voltage DC through a high-frequency transformer, converting it into two low-voltage DC outputs.

[0051] The first output is the drive voltage. (Typical values ​​are 12V or 24V), this output is directly connected to the control coil power supply terminal of the power switching unit 220. The secondary winding parameters of the high-frequency transformer are configured to ensure... It can provide sufficient pull-in power to drive high-power relays or contactors.

[0052] The second output is further stepped down and regulated by a linear regulator (LDO) module to generate the logic voltage. (Typical values ​​are 3.3V or 5V). Logic voltage The power supply pin (VCC) is connected to the microcontroller unit 210 and the first wireless communication unit 230.

[0053] To ensure system stability under power grid fluctuations, the auxiliary power supply unit 240 integrates an undervoltage lockout circuit. The effective value of the input AC voltage is defined as... The minimum threshold voltage for the system to maintain normal operation is Operating status of auxiliary power supply unit 240 The following logical relationship must be satisfied:

[0054] ;

[0055] in, Indicates the effective value of the input AC voltage; This represents the minimum threshold voltage required for the system to maintain normal operation. This indicates a logical true state, corresponding to the normal output of auxiliary power supply unit 240; This indicates a logical false state, corresponding to the auxiliary power supply unit 240 output being turned off; This is a conditional flag indicating that the working state occurs if and only if the logical conditional expression that follows it is satisfied. Retrieve the value corresponding to that row.

[0056] when At that time, the auxiliary power supply unit 240 was outputting normally. and ;when When the power supply is interrupted, the output is turned off and the system automatically resets to prevent contact erosion caused by insufficient voltage causing the power switching unit 220 to not engage properly. This adaptive power supply logic ensures the system's safety even in situations where the power supply quality in the feed mill is poor.

[0057] See attached document Figure 2 This embodiment details how the identity authentication subsystem configured inside the mobile interactive terminal 300 achieves automated verification of operator qualifications through software algorithms and logical judgments.

[0058] The identity authentication subsystem is logically divided into an image acquisition module, a feature extraction module, and a compliance determination module. The image acquisition module is connected to the data interface of the image acquisition unit 310 and is configured to control the camera to perform optical imaging of the special operation certificate and convert the analog light signal into a digital image matrix.

[0059] The feature extraction module receives a digital image matrix and runs an Optical Character Recognition (OCR) algorithm. This OCR algorithm is configured to segment the document layout, locate text regions containing key information, and convert the image text into computer-encodeable character data. The structured user feature dataset is defined as follows: This user feature dataset contains feature elements in four dimensions:

[0060] ;

[0061] in, This represents a user feature dataset that has undergone structured processing. This represents the name feature element extracted from the document image; This represents the ID card number feature element extracted from the ID card image; This represents the job category feature elements extracted from the document image; This represents the feature element representing the certificate expiration date extracted from the document image.

[0062] The compliance determination module is the core execution unit of the authentication logic. This module contains a pre-built set of work category permissions. In response to the equipment maintenance needs of feed production enterprises, The system stores job category strings that conform to national standards, specifically including welding and thermal cutting operations. Simultaneously, the compliance determination module reads the current real-time date data through the system clock interface. .

[0063] The compliance determination module is equipped with a logic comparator, which executes the following authentication logic function to output a verification status value. :

[0064] ;

[0065] in, This indicates a logical true state, corresponding to the state where the qualification verification has passed. This indicates a logical false state, corresponding to a state where qualification verification has failed. This is a conditional flag, indicating that a verification status value is output if and only if the logical conditional expression that follows it is satisfied. Retrieve the value corresponding to that row; Indicates when the above conditions are not met When the conditions for guidance are met, output the verification status value. Retrieve the value corresponding to that row; This represents the job category feature element extracted from the certificate; This represents the set of pre-defined job category licenses in the system. The set membership operator is used to determine set membership. Does it belong to ; This represents the feature element representing the certificate expiration date extracted from the document image; This indicates the current real-time date data.

[0066] When the compliance assessment module outputs the verification status value for When the system determines that the current operation qualification is valid, it triggers the subsequent communication module to generate a digital access token; when the verification status value is output... for When the system determines that the qualification is invalid, it terminates all subsequent data interaction processes, thereby blocking operation requests that do not comply with the safety standards of the feed mill at the software logic level.

[0067] This embodiment details how the communication encryption module inside the mobile interactive terminal 300 is configured to establish a secure data transmission link in the complex electromagnetic environment of feed production.

[0068] The communication encryption and handshake module is configured in the data processing unit 320 of the mobile interactive terminal 300. This module is configured to first call the image acquisition unit 310 to acquire the optical identification tag information on the surface of the smart control terminal 200, and then decode the unique identifier of the target device from it. Simultaneously, the communication encryption and handshake module receives the digital access token generated by the identity authentication subsystem via the internal bus. This digital access token is a unique session credential generated after the operator's qualifications have been verified.

[0069] To prevent malicious interception and replay of communication commands or timing disruptions caused by network latency, the communication encryption and handshake module is equipped with a clock synchronization unit to obtain the current system timestamp. The system's timestamps are accurate to the millisecond level and participate in encryption operations as dynamic factors.

[0070] The communication encryption and handshake module integrates a hash operation engine. This hash operation engine is configured to perform one-way encryption logic, concatenating the device identifier, digital access token, and timestamp in a predetermined order, and generating a fixed-length encrypted verification code using a secure hash algorithm (such as SHA-256). Encryption verification code The generation follows the following formula:

[0071] ;

[0072] in, This represents the generated encrypted verification code, used by the receiving end to verify the integrity and legitimacy of the command; This indicates the system's pre-defined secure hash function algorithm; A unique identifier for the intelligent control terminal 200; This represents the data concatenation operator, used to chain multiple data fields together bitwise. This represents a digital access token generated after authentication. The system timestamp indicating when the instruction was generated.

[0073] The communication encryption and handshake module is also equipped with a data packetization unit. This data packetization unit is configured to construct wireless data transmission frames and include the system timestamp. Plaintext data and encryption verification code The encrypted data is encapsulated within the data payload segment of the same data packet. This data packet is then transmitted to the intelligent control terminal 200 via the second wireless communication unit 330. This configuration ensures that the content transmitted over the wireless channel does not contain plaintext user-sensitive information or device control keys; only hash values ​​and time parameters used for verification are transmitted.

[0074] See attached document Figure 3 This embodiment details the internal logic configuration of how the microcontroller unit 210 inside the intelligent control terminal 200 parses and verifies the received wireless data packets and generates drive signals accordingly.

[0075] The terminal verification and execution module operates in the firmware layer of the microcontroller unit 210. After receiving a data packet from the mobile interactive terminal 300, the first wireless communication unit 230 transmits the data payload to the input buffer of the microcontroller unit 210 via a serial communication interface. The terminal verification and execution module first initiates the unpacking procedure to extract the received encryption verification code from the data payload. and the received timestamp .

[0076] To defend against replay attacks and ensure the timeliness of control commands, the terminal verification and execution module is configured with time window comparison logic. This module reads the current system time from the internal real-time clock of the microcontroller unit 210. And set the maximum allowable latency threshold. To address the real-time requirements of feed production environments, It is preset to a constant (e.g., 3000 milliseconds). Time validity state. The determination follows the absolute difference inequality formula:

[0077] ;

[0078] in, Indicates the time validity status. This indicates a logically true state, corresponding to a successful time check. This indicates a logical false state, corresponding to a failed time check. This indicates the current system time of the internal real-time clock of the microcontroller unit 210; This represents the timestamp parsed from the received data packet; This indicates the system's preset maximum allowable latency threshold; This is a conditional flag indicating that the time validity state is true if and only if the logical conditional expression that follows it is satisfied. Retrieve the value corresponding to that row; Indicates when the above conditions are not met When guided, the time validity state is... Retrieve the value corresponding to that row.

[0079] The time validity determination is passed (i.e.) Under the premise of [condition], the terminal verification and execution module initiates the hash integrity comparison logic. This terminal verification and execution module calls the unique identifier of the local device pre-stored in the memory. and the currently valid session token Combined with the received timestamp The local hash value is recalculated using the same secure hash algorithm as the sender. Subsequently, the terminal verification and execution module performs a consistency comparison using the following formula:

[0080] ;

[0081] in: This indicates the result of the judgment on data integrity and legality of its source. This indicates a logically true state, corresponding to a successful hash check. This indicates a logical false state, corresponding to a verification failure. This indicates that the microcontroller unit 210 recalculates the generated local hash value locally; This represents the original encrypted checksum parsed from the received data packet; This represents the identity comparison operator, used to determine whether each bit of two data sequences is exactly the same.

[0082] The terminal verification and execution module generates the final action command based on the results of the above two verification steps. Only when... and At the same time At that time, the microcontroller unit 210 will verify the authentication result variable. Set as This triggers the GPIO port to output a high-level drive signal, closing the power on / off unit 220; otherwise, the microcontroller unit 210 remains open. for The system logs a verification failure event and ensures that the welding machine can only be powered on and operate when it receives a fresh, digitally signed, and legitimate instruction.

[0083] See attached document Figure 4 This embodiment details how the intelligent control terminal 200 continuously monitors its own working status through internal logic configuration during power-on operation, and automatically performs a safety reset when an abnormal state is detected, so as to ensure electrical safety in the feed production environment.

[0084] The status monitoring and safety reset logic is configured in the microcontroller unit 210 as firmware. To implement this logic, the firmware includes a heartbeat communication monitoring module and a job duration monitoring module, which work together through periodically executed internal tasks and interrupt service routines.

[0085] The heartbeat communication monitoring module is internally equipped with a heartbeat timer to monitor the wireless communication link status between the module and the mobile interactive terminal 300. When the power on / off unit 220 successfully closes and the welding machine main unit 100 begins operation, the heartbeat timer is initialized and started. The mobile interactive terminal 300 is configured to send heartbeats at authorized intervals during authorized use. (For example, every 1000 milliseconds) send an encrypted and verified heartbeat data packet to the intelligent control terminal 200.

[0086] Each time the microcontroller unit 210 receives a valid heartbeat data packet (i.e., passes the aforementioned dual verification of time validity and hash integrity), it resets the heartbeat timer's count. If the accumulated heartbeat timer count exceeds a preset timeout threshold... The system then determines that the wireless communication link has been interrupted. Timeout threshold. The setting is slightly larger than the heartbeat sending interval. This allows for tolerance of single packet loss.

[0087] The operation duration monitoring module is internally equipped with another operation duration timer. This timer starts the instant the power switching unit 220 closes to limit the duration of a single continuous operation, preventing operators from neglecting fire prevention requirements in the feed production environment due to prolonged continuous welding. The maximum allowable duration of a single continuous operation is defined as follows: This value is preset according to the feed mill's internal safety management procedures (e.g., 30 minutes).

[0088] The microcontroller unit 210, through its internal logic, classifies both communication interruption events and timeout events as system faults. System fault monitoring variables. The state is determined by the following logical expression:

[0089] ;

[0090] in, This represents a system fault monitoring variable, and its value is... This indicates that a communication failure or hardware malfunction has been detected. This indicates the status of a heartbeat communication timeout event; when the heartbeat timer count exceeds [a certain value]. hour, Set as Otherwise ; Represents the logical OR operator; This indicates the status of a single work duration timeout event; when the work duration timer count exceeds... hour, Set as Otherwise .

[0091] once The value becomes According to the formula The control signal status output by the microcontroller unit 210 Will force become This change in state causes the drive circuit to shut down, the control coil of the power switching unit 220 to lose power, and the internal mechanical reset spring drives the main contacts to open, thereby cutting off the power supply to the main welding machine unit 100. This forced power-off reset mechanism ensures that the welding equipment can automatically return to a safe power-off state in abnormal situations such as the operator leaving the work area, the mobile terminal running out of power, or exceeding the predetermined working time.

[0092] This embodiment details how the intelligent control terminal 200 can be adapted to more powerful three-phase power equipment commonly found in feed mills, such as high-power pellet mills or mixers, to achieve safe control of their main power supply.

[0093] The power extension embodiment is achieved by introducing industrial-grade three-phase AC contactors. The main contacts (L1 / T1, L2 / T2, L3 / T3) of the three-phase AC contactors are configured to be connected in series between the external three-phase power grid and the main power cable of the large feed equipment. The rated current and breaking capacity of the main contacts of the contactors are selected based on the rated power of the controlled equipment to carry the full-load current during equipment startup and operation.

[0094] In this embodiment, the power switching unit 220 inside the intelligent control terminal 200 no longer directly controls the main load current, but instead becomes an intermediate control element. The normally open contacts of the power switching unit 220 (which can be a small relay) are configured to be connected in series in the control coil circuit of a three-phase AC contactor. The power supply for this control coil circuit is obtained from a phase of the external power grid or a dedicated control power supply.

[0095] The circuit structure and logic configuration of the microcontroller unit 210, the first wireless communication unit 230, and the auxiliary power supply unit 240 inside the intelligent control terminal 200 remain unchanged. After the operator completes identity authentication through the mobile interactive terminal 300, the mobile interactive terminal 300 still generates and sends encrypted control commands.

[0096] After receiving and successfully verifying the control command, the microcontroller unit 210 of the intelligent control terminal 200 also drives its GPIO port to output a high-level signal. This high-level signal, through the isolation drive circuit, energizes the control coil of the power switching unit 220 (small relay), causing its normally open contacts to close.

[0097] When the contacts of the power switching unit 220 close, the control coil circuit of the three-phase AC contactor is connected. After the coil of the three-phase AC contactor obtains its rated operating voltage (e.g., AC220V or AC380V), it generates a strong electromagnetic attraction, driving its three pairs of main contacts to close simultaneously, thereby connecting the three-phase main power supply to the large feed equipment downstream.

[0098] When communication is interrupted, operation timeout occurs, or an operator sends a power-off command via the mobile interactive terminal 300, the microcontroller unit 210 of the intelligent control terminal 200 stops outputting GPIO high-level signals. This causes the coil of the power switching unit 220 to lose power, its contacts open, and thus the coil circuit of the three-phase AC contactor is cut off. After the three-phase AC contactor coil loses power, its three pairs of main contacts simultaneously and quickly open under the action of the reset spring, reliably cutting off the main power supply to the large feed equipment.

[0099] Through this two-level control structure, the present invention utilizes a low-power, high-reliability intelligent control terminal 200 to safely realize remote authorized control of three-phase power equipment of any power level in a feed mill, and all core security authentication and monitoring logics do not need to be changed.

[0100] This embodiment details an alternative solution for ensuring system communication stability by replacing communication technologies to address severe electromagnetic interference generated by equipment such as frequency converters and high-power motors in feed production workshops.

[0101] In this alternative embodiment, the first wireless communication unit 230 of the intelligent control terminal 200 and the second wireless communication unit 330 of the mobile interactive terminal 300 are both replaced with power line communication (PLC) modules.

[0102] The physical interface of the PLC communication module of the mobile interactive terminal 300 is connected to any standard power outlet of the external power grid via a dedicated coupling plug. The PLC communication module is configured to modulate the digital data frame to be sent (including timestamp, encryption check code, and other information) onto a specific carrier frequency and superimpose this high-frequency signal onto 220V AC power for transmission.

[0103] The PLC communication module of the intelligent control terminal 200 has its coupling circuit directly connected in parallel to the input terminal of its auxiliary power supply unit 240, i.e., physically connected to the phase and neutral lines of the external power grid. This PLC communication module is configured to continuously monitor the carrier signal on the power line and filter out power frequency and other noise signals using a bandpass filter, extracting only signals within a specific carrier frequency range. Subsequently, the PLC communication module demodulates the extracted signal, restores it to a digital data frame, and transmits it to the microcontroller unit 210 for subsequent verification processing.

[0104] Since the transmission medium for data signals is the metal conductors of the power grid itself, power line carrier communication technology has a natural shielding effect against electromagnetic interference originating from space radiation, compared to radio frequency signals that propagate in the air, and its anti-interference capability is significantly enhanced.

[0105] To distinguish different control pairs on a shared power line channel and prevent conflicts with other potential power line carrier devices within the workshop, this embodiment introduces the concept of a network ID. Upon initial pairing, the mobile interactive terminal 300 generates a unique network identifier. The network identifier It is a separate field that is sent along with the timestamp and encrypted verification code.

[0106] The intelligent control terminal 200 receives the first valid... After the command is executed successfully, this will be... The data is stored in its internal non-volatile memory. Afterwards, the PLC module of the intelligent control terminal 200, after demodulating the data, will execute a network attribution determination logic:

[0107] ;

[0108] in, This indicates the result of the network affiliation matching. This indicates a logically true state, corresponding to a successful match. This indicates a logical false state, corresponding to a failed match. This represents the network identifier parsed from the currently received data frame; This indicates the local network identifier stored when the intelligent control terminal 200 is first paired; This represents the identity comparison operator, used to determine whether two data sequences are completely identical.

[0109] Only when for Only then will the microcontroller unit 210 continue to perform subsequent time validity and hash integrity checks. This logical configuration ensures that even if multiple control systems of this invention exist under the same power grid, each mobile interactive terminal 300 can only control its bound target device, avoiding the risk of cross-control. This solution provides a more reliable communication method for industrial sites with harsh electromagnetic environments without changing the core security authentication and control logic.

[0110] This embodiment details how to further improve the safety level of the system in the special environment of feed production by adding environmental sensors and incorporating the sensor data into the control logic.

[0111] In this extended embodiment, the intelligent control terminal 200 is physically connected to one or more environmental monitoring sensors through its reserved I / O expansion interface. Considering the characteristics of feed production workshops, which contain large amounts of dust and flammable materials, the environmental monitoring sensors are specifically combustible gas concentration sensors or dust concentration sensors.

[0112] The environmental monitoring sensor is configured to measure the concentration of combustible gases or dust in the surrounding air in real time and convert the concentration value into an analog voltage signal or a standard digital signal (such as I2C or SPI) output. The microcontroller unit 210 of the intelligent control terminal 200 is configured to periodically read the environmental monitoring sensor data through its built-in analog-to-digital converter (ADC) or a corresponding digital communication interface.

[0113] The firmware layer of the microcontroller 210 has a preset safe concentration threshold. This safe concentration threshold is set according to national safety production standards or specific fire and explosion prevention regulations for the feed industry. The microcontroller unit 210 will read the real-time concentration value. With safe concentration threshold Perform continuous comparisons. Environmental safety status variables. Determined by the following logical functions:

[0114] ;

[0115] in, Represents environmental safety state variables. This represents a logically true state, corresponding to environmental safety. This indicates a logical false state, corresponding to an environmental hazard. This indicates the real-time concentration value measured by environmental monitoring sensors; This indicates the system's preset safe concentration threshold.

[0116] The core control signal drive logic within the microcontroller unit 210 is extended to include environmental safety status as a mandatory prerequisite. The final control signal state of the drive power on / off unit 220 is defined in this embodiment as... It is determined by the following enhanced logical expression:

[0117] ;

[0118] in, This indicates the final control signal state, which incorporates the environmental safety status. This indicates a logical true state, corresponding to an output ON signal. This indicates a logical false state, corresponding to an output disconnect signal; This represents the control signal state obtained from the aforementioned calculations, and its value is determined by... Decide; The result indicating the environmental safety status; This represents the logical AND operator.

[0119] This logic configuration ensures that not only do compliant operators need to issue legitimate control commands and the system itself need to be fault-free, but the work site environment must also be safe (i.e., the concentration of flammable gas or dust must be below the alarm threshold) before the power switching unit 220 can be closed. Once the environmental monitoring sensor detects that the concentration exceeds the standard during welding operations (i.e.,...), the power switching unit 220 will close. Become Regardless of whether the operator issues an instruction, the final control signal The value will be immediately forced to become This triggers an immediate power outage, effectively cutting off the welding ignition source. This closed-loop control logic, linked to environmental conditions, provides proactive and automated safety assurance for temporary hot work operations in high-dust environments such as feed crushing and mixing.

Claims

1. A foolproof system for welding machines based on feed production, characterized in that, include: The main unit of the welding machine includes a power input interface and a welding circuit. The power input interface is used to receive AC power, and the welding circuit is electrically connected to the power input interface. The intelligent control terminal is connected in series and fixedly connected to the power supply circuit of the main unit of the welding machine. The intelligent control terminal includes a housing and a microcontroller unit, a power switching unit, a first wireless communication unit and an auxiliary power supply unit encapsulated inside the housing. The front-end physical circuit of the power input interface is cut off and connected in series with the intelligent control terminal. The mobile interactive terminal establishes a wireless data communication link with the intelligent control terminal through a wireless communication protocol. The mobile interactive terminal is configured to collect image information of special operation certificates and verify operation qualifications, and after verification, generate a data packet containing control instructions and send it to the intelligent control terminal. The first wireless communication unit is configured to receive the data packet and transmit it to the microcontroller unit; The microcontroller unit is configured to verify the data packet and send a drive signal to the power on / off unit based on the verification result; The power switching unit is connected in series between the external power grid and the power input interface, and is used to perform the closing or opening action of the physical contacts according to the drive signal, thereby controlling the power supply status of the main unit of the welding machine.

2. The error-proofing system for welding machines based on feed production according to claim 1, characterized in that, The power switching unit is a normally open relay or AC contactor. The control coil circuit and the main contact circuit of the power switching unit are electrically isolated from each other. In the absence of the drive signal input, the power switching unit is kept in the open position under the action of the mechanical reset spring, thereby blocking the transmission of electrical energy to the main unit of the welding machine. The input terminal of the auxiliary power supply unit is connected in parallel to the front end of the power switching unit and directly connected to the external power grid. The output terminal of the auxiliary power supply unit is electrically connected to the power supply terminals of the microcontroller unit and the first wireless communication unit, respectively, so as to maintain the microcontroller unit and the first wireless communication unit in a powered working state when the power switching unit is in the off state.

3. The error-proofing system for welding machines based on feed production according to claim 1, characterized in that, An isolation drive circuit module is provided between the microcontroller unit and the power switching unit. The isolation drive circuit module includes an optocoupler, a switching transistor, and a freewheeling diode. The microcontroller unit runs a logic operation program to generate control signal states, which depend on the result of a logical AND operation performed on the logical NOT result of the authentication verification result variable and the system fault monitoring variable. When the control signal is in a logical true state, the microcontroller controls the general-purpose input / output port to output a high level, driving the control coil of the power switching unit to be energized and engaged. When the control signal is in a logical false state, the drive signal stops outputting and the power on / off unit is disconnected.

4. The error-proofing system for welding machines based on feed production according to claim 1, characterized in that, The mobile interactive terminal includes an image acquisition unit and a data processing unit; The data processing unit is configured to execute an optical character recognition algorithm to convert the collected image information into a user feature dataset containing name feature elements, ID card number feature elements, job category feature elements, and certificate expiration date feature elements. The data processing unit is internally configured with a compliance determination module. This module executes authentication logic functions and outputs a verification status value. The condition for the verification status value to be deemed valid is: The job category feature element belongs to a preset job category license set, and the certificate expiration date feature element is later than the current real-time date data; When the verification status value is determined to be valid, the data processing unit generates a digital access token.

5. The error-proofing system for welding machines based on feed production according to claim 4, characterized in that, The mobile interactive terminal is equipped with a communication encryption and handshake module, which is configured to obtain the unique device identifier of the smart control terminal, the digital access token, and the current system timestamp. The communication encryption and handshake module uses a secure hash algorithm to concatenate the unique device identifier, the digital access token, and the system timestamp in a predetermined order to generate an encrypted verification code. The communication encryption and handshake module constructs a wireless data transmission frame, encapsulates the plaintext data of the system timestamp and the ciphertext data of the encryption verification code in the data payload segment of the data packet, and sends it to the intelligent control terminal.

6. The error-proofing system for welding machines based on feed production according to claim 5, characterized in that, The microcontroller unit internally operates a terminal verification and execution module, which is configured to parse the received encrypted verification code and timestamp from the received data packet; The validity status determination of the execution time of the terminal verification and execution module is based on the following conditions: The absolute value of the difference between the current system time of the real-time clock inside the microcontroller and the received timestamp is less than or equal to the preset maximum allowable delay threshold. The terminal verification and execution module performs a data integrity determination, and the determination condition is that the local hash value recalculated by the microcontroller using the stored unique identifier of the local device, the currently valid session token, and the received timestamp is completely consistent with the received encrypted verification code. The microcontroller sets the authentication result variable to logical true only when both the time validity status determination and the data integrity determination are passed.

7. The error-proofing system for welding machines based on feed production according to claim 3, characterized in that, The microcontroller unit is equipped with a heartbeat communication monitoring module and an operation duration monitoring module. The heartbeat communication monitoring module is used to monitor the count value of the heartbeat timer. When the count value of the heartbeat timer exceeds the preset timeout threshold, it is determined as a heartbeat communication timeout event. The work duration monitoring module is used to monitor the count value of the work duration timer. When the count value of the work duration timer exceeds the preset maximum allowable duration of a single continuous work, it is determined as a single work duration timeout event. The state of the system fault monitoring variable is determined by the logical OR operation result of the state of the heartbeat communication timeout event and the state of the single working duration timeout event. When the system fault monitoring variable is logically true, the microcontroller unit forcibly disconnects the power on / off unit.

8. The error-proofing system for welding machines based on feed production according to claim 1, characterized in that, The power switching unit is connected in series in the control coil circuit of the three-phase AC contactor, and the main contacts of the three-phase AC contactor are connected in series between the external power grid and the main power cable of the high-power feed equipment. The microcontroller unit controls the opening and closing of the power switching unit contacts, thereby controlling the coil of the three-phase AC contactor to be energized or de-energized, thus realizing the connection or disconnection of the main power supply of the high-power feed equipment.

9. The error-proofing system for welding machines based on feed production according to claim 1, characterized in that, Both the first wireless communication unit and the second wireless communication unit of the mobile interactive terminal are power line carrier communication modules; The power line carrier communication module is configured to modulate a data frame containing a network identifier, a timestamp, and an encryption check code onto a carrier frequency and superimpose it onto the power frequency AC for transmission. The microcontroller unit is configured to execute network attribution determination logic before performing verification. The pass condition for the network attribution determination logic is: The network identifier parsed from the received data frame is completely consistent with the local network identifier stored in the smart control terminal.

10. A foolproof welding machine system based on feed production according to claim 3, characterized in that, The intelligent control terminal is electrically connected to an environmental monitoring sensor, which is used to detect the concentration of combustible gas or dust in the environment. The microcontroller unit is configured to read the real-time concentration value output by the environmental monitoring sensor and compare the real-time concentration value with a preset safe concentration threshold to generate an environmental safety status variable; The final control signal state driving the power switching unit is determined by the logical AND operation result of the control signal state and the environmental safety state variable; When the real-time concentration value is greater than or equal to the safe concentration threshold, the final control signal state is forced to logical false, and the power on / off unit is disconnected.

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