Grounding detection system of handheld welding equipment and use method

Abstract

The invention provides a grounding detection system of handheld welding equipment and a use method, and belongs to the technical field of equipment grounding detection. The system comprises a strong current connection interface and a signal transmission interface; the strong current connection interface is connected with a phase line, a zero line and a protective ground wire of handheld welding equipment, and the signal transmission interface is connected with the control panel; the signal transmission interface is connected with a grounding detection sampling unit and a detection control unit; the grounding detection sampling unit, the strong current connection interface and the signal transmission interface form a detection loop; the control panel of the handheld welding equipment controls the on-off of the detection loop through the detection control unit, detects the grounding resistance of the handheld welding equipment through the grounding detection sampling unit, and gives an alarm and cuts off the detection loop when the grounding resistance exceeds a configured grounding resistance threshold value. Through cooperative work of strong current connection and signal transmission, the grounding detection precision and efficiency of the welding equipment are improved, an alarm is automatically given, a circuit is cut off, the safety of operators is guaranteed, and the equipment damage risk is reduced.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of equipment grounding detection, and particularly relates to a grounding detection system of a handheld welding equipment and a use method. BACKGROUND

[0002] In an industrial environment, handheld laser welding equipment is widely used in various complex work scenarios, in which there are often a large number of strong interference equipment, such as high-power motors, frequency converters, etc. The electromagnetic interference generated by these equipment may seriously affect the normal operation of the welding equipment. In order to ensure the stable operation of the equipment and the safety of the operator, good grounding treatment is crucial. However, the traditional grounding detection method has the following problems: Firstly, the detection accuracy is insufficient. The conventional grounding detection method is prone to failure when the equipment power consumption is large (such as more than 5000W) or there is a leakage voltage (such as 110VAC), and cannot accurately reflect the true grounding state. Secondly, there is a safety hazard. When the grounding wire is not connected correctly, the equipment metal shell may be live (such as with 110VAC leakage voltage), which poses a serious risk of electric shock, and the traditional grounding detection method cannot timely cut off the dangerous circuit. Thirdly, the traditional grounding detection method also lacks real-time monitoring and alarm function for the grounding state, and the operator is difficult to find the poor grounding problem in time, which may cause equipment damage or welding quality decline. Finally, it has poor adaptability. In a complex electromagnetic environment, the traditional grounding detection method is easily disturbed, leading to misjudgment or omission, affecting the reliability of the equipment. SUMMARY

[0003] In a first aspect, the embodiments of the application provide a grounding detection system of a handheld welding equipment, comprising a strong current connection interface and a signal transmission interface; The strong current connection interface is connected with the phase line, the zero line and the protective ground line of the handheld welding equipment, and the signal transmission interface is connected with the control board of the handheld welding equipment; The signal transmission interface is connected with a grounding detection sampling unit and a detection control unit; The grounding detection sampling unit forms a detection loop with the strong current connection interface and the signal transmission interface; The control board of the handheld welding equipment controls the on-off of the detection loop through the detection control unit, detects the grounding resistance of the handheld welding equipment through the grounding detection sampling unit, and when the grounding resistance exceeds the configured grounding resistance threshold, alarms and cuts off the detection loop.

[0004] Further, the signal transmission interface adopts a four-core signal line interface, including a power terminal, a grounding end, a sampling signal end and a detection control end. The strong current connection interface is provided with a phase line end, a zero line end and a ground line end, the phase line end is connected with the phase line of the handheld welding device, the zero line end is connected with the zero line of the handheld welding device, and the protection ground line end is connected with the protection ground line of the handheld welding device.

[0005] Further, the detection control unit comprises a relay RYL1, a transistor Q1 and a diode D1. The relay RYL1 comprises a control coil and a controlled normally open switch. The base of the transistor Q1 is connected with a resistor R1 and a resistor R2, the other end of the resistor R1 is connected with the detection control end of the signal transmission interface, the other end of the resistor R2 is connected with the emitter of the transistor Q1 and grounded. The first end of the control coil of the relay RYL1 is connected with the negative electrode of the diode D1 and the power terminal of the signal transmission interface, and the power terminal is connected with the power supply of the controlled board of the handheld welding device. The second end of the control coil of the relay RYL1 is connected with the positive electrode of the diode D1 and the collector of the transistor Q1. The controlled normally open switch of the relay RYL1 is arranged in the detection loop. The ground end of the signal transmission interface is grounded.

[0006] Further, the ground detection sampling unit comprises a current transformer L1, a diode D2 and a voltage stabilizing diode D3. The current transformer L1 is provided with a strong current side and a weak current side. The first end of the strong current side is connected with a resistor R8, the other end of the resistor R8 is connected with the first end of the controlled normally open switch of the relay RYL1, and the second end of the controlled normally open switch of the relay RYL1 is connected with a resistor R4 and a resistor R7. The other end of the resistor R4 is connected with the phase line end of the strong current connection interface, and the other end of the resistor R7 is connected with the zero line end of the strong current connection interface. The second end of the strong current side is connected with the ground line end of the strong current connection interface. The first end of the weak current side is connected with a resistor R6 and connected with the positive electrode of the diode D2, and the other end of the resistor R6 is connected with the second end of the weak current side and grounded. The negative electrode of the diode D2 is connected with a resistor R3, the other end of the resistor R3 is connected with a resistor R5, a capacitor C1 and the negative electrode of the voltage stabilizing diode D3 and the sampling signal end of the signal transmission interface. The other end of the resistor R5 is connected with the other end of the capacitor C3 and the positive electrode of the voltage stabilizing diode D3 and grounded.

[0007] In the second aspect, the embodiments of the present application further provide a use method of the ground detection system of the handheld welding device in the first aspect, comprising the following steps: S1. Connect the strong electricity connection interface with the phase line, zero line and protective ground line of the handheld welding device, and connect the signal transmission interface with the control board of the handheld welding device; S2. Power on the handheld welding device, and initialize the sampling signal end and detection control end connected by the signal transmission interface of the control board of the handheld welding device, configure the ground resistance threshold value and the sampling frequency of the sampling signal end; S3. The control board of the handheld welding device sends a signal to the detection control unit through the detection control end of the signal transmission interface, closes the detection loop, and collects the detection loop current through the ground detection sampling unit, and calculates the ground resistance value according to the detection loop current; S4. The control board of the handheld welding device judges whether the calculated ground resistance value is less than the configured ground resistance threshold value; If yes, go to step S6; If no, it is determined that the ground of the handheld welding device is normal, and step S5 is entered; S5. Repeat the steps of steps S3-S4 according to the set detection period to perform ground detection; S6. It is determined that the ground of the handheld welding device is abnormal, the detection control unit is disconnected, and ground abnormality alarm is performed.

[0008] Further, the specific steps of step S2 are as follows: S21. The control board of the handheld welding device pre-stores a scene-resistance threshold mapping table, and the scene-resistance threshold mapping table contains ground resistance threshold values corresponding to different application scenarios; S22. Receive the application scenario selected by the user, and load the corresponding ground resistance threshold value from the scene-resistance threshold mapping table ; S23. Calculate the reference voltage according to the circuit parameters of the ground detection sampling unit, and then calculate the ground resistance threshold value corresponding voltage threshold , and then convert the voltage threshold into alarm digital quantity threshold ; S24. Receive the sampling frequency f configured by the user.

[0009] Further, the specific steps of step S23 are as follows: S231. Obtain the turns ratio n of the current transformer L1, ; Obtain the resistance value of the resistor R8, denoted as R8; Obtain the resistance value of the resistor R6, denoted as R6; S232. Mark the output voltage of the weak side of the ground detection sampling unit as the actual output voltage, denoted as ; The output voltage of the weak current side of the ground detection sampling unit is marked as the actual output voltage, and is marked as ;

[0010]

[0011] wherein, is the loop current of the high voltage side of the ground detection sampling unit, is the equivalent voltage of the high voltage side of the ground detection sampling unit, is the protective ground voltage; S233. Set the actual output voltage when the ground resistance is 0 corresponding to the actual output voltage is the reference voltage ; S234. Calculate the ground resistance threshold value corresponding to the reference ground resistance value corresponding to the voltage threshold value ;

[0012] S235. According to the ADC bit number d of the control panel of the handheld welding device and the power supply voltage VCC, the voltage threshold value is converted into the alarm digital quantity threshold value ; .

[0013] Further, the step S3 is specifically as follows: S31. The control panel of the handheld welding device controls the triode Q1 to close through the detection control end of the signal transmission interface, so as to control the relay RYL1 to close the high voltage side of the detection loop and start sampling; S32. The high voltage side of the detection loop generates a loop current , and the low voltage side of the detection loop generates a current , and the voltage value generated by the resistor R6 is rectified by the diode D2 and stabilized by the voltage stabilizing diode D3, thereby generating an output voltage ;

[0014] wherein, n is the number of turns ratio of the current transformer L1; S33. The control panel of the handheld welding device collects the output voltage according to the set sampling frequency through the sampling signal end of the signal transmission interface, and converts it into a digital quantity until the set sampling number is met, and then averages the sampled digital quantity to obtain a digital quantity average value .​

[0015] Further, the control panel of the handheld welding device in step S4 compares the digital average value with the alarm digital threshold . If , step S6 is entered; If , it is determined that the handheld welding device ground is normal, and step S5 is entered; Step S5 has the following specific steps: S51. Obtain the set detection period and determine whether the detection time is reached; If yes, step S52 is entered; If no, wait for a set period of time and return to step S51; S52. Perform steps S3-S4 to detect the ground.

[0016] Further, step S6 has the following specific steps: S61. The control panel of the handheld welding device outputs a low-level signal through detection control, so that the transistor Q1 is cut off, the relay RLY1 is disconnected, and the detection circuit is cut off; S62. Generate a ground abnormality alarm information and write it into the system memory, trigger an audible and light alarm, and perform alarm display through the display screen of the handheld welding device; S63. Lock the welding function of the handheld welding device, generate a fault log, and until manual reset and ground fault is eliminated.

[0017] From the above technical solution, the present application has the following advantages: The ground detection system and use method of the handheld welding device provided by the present application can accurately detect the ground resistance and timely alarm and cut off the detection circuit when the ground is poor, thereby reducing the risk of electric shock of the operator and ensuring that the device operates in a safe grounding state. Through the sampling unit and the signal processing circuit, the ground resistance can be accurately measured in a complex electromagnetic environment, avoiding the problem of detection failure of the traditional detection method in high-power equipment or in the presence of leakage voltage.

[0018] The present application can be applied to various application scenarios. By configuring different ground resistance thresholds, the ground detection requirements in different industrial environments can be met, the versatility and flexibility of the handheld welding device are improved, and the function of real-time monitoring of the grounding state is provided. Once it is found that the ground resistance exceeds the set threshold, an alarm is immediately issued to remind the operator to handle it in time, avoiding damage to the device and welding quality problems caused by poor grounding. The entire detection process has high automation degree, reduces manual intervention, improves work efficiency, and can automatically record alarm information and fault logs, facilitating subsequent maintenance and fault analysis. BRIEF DESCRIPTION OF DRAWINGS

[0019] In order to more clearly illustrate the technical solutions of the present application, the drawings required to be used in the description will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative effort on the basis of these drawings.

[0020] Figure 1 The overall schematic diagram of the grounding detection system of the handheld welding device of the present application.

[0021] Figure 2 The circuit schematic diagram of the grounding system of the handheld welding device of the present application.

[0022] Figure 3 The flowchart schematic diagram of the use method of the grounding system of the handheld welding device of the present application.

[0023] Among them, 1-handheld welding device; 2-control panel; 3-grounding detection sampling unit; 4-detection control unit; CN1-signal transmission interface; JP1-high-voltage connection interface. DETAILED DESCRIPTION

[0024] In the following detailed description of the grounding detection system of the handheld welding device, various embodiments of the present disclosure will be described more fully. The present disclosure can have various embodiments, and adjustments and changes can be made therein. However, it should be understood that there is no intention to limit various embodiments of the present disclosure to the specific embodiments disclosed herein, but the present disclosure should be understood to cover all adjustments, equivalents and / or alternatives falling within the spirit and scope of various embodiments of the present disclosure.

[0025] Exemplarily, in an industrial environment, handheld laser welding devices are widely used in various complex work scenarios, in which there are often a large number of strong interference devices such as high-power motors, frequency converters, etc., and the electromagnetic interference generated by these devices can seriously affect the normal operation of the welding device. In order to ensure stable operation of the device and safety of the operator, good grounding treatment is crucial. However, the traditional grounding detection method has the following problems: First, the detection accuracy is insufficient. The conventional grounding detection method is prone to failure when the device power consumption is large (such as more than 5000W) or there is a leakage voltage (such as 110VAC), and cannot accurately reflect the true grounding state. Second, there is a safety hazard. When the grounding wire is not properly connected, the device metal shell may be live (such as with a 110VAC leakage voltage), posing a serious risk of electric shock, and the traditional grounding detection method cannot timely cut off the dangerous circuit. Third, the traditional grounding detection method also lacks real-time monitoring and alarm functions for the grounding state, making it difficult for operators to timely discover poor grounding problems, which may lead to equipment damage or reduced welding quality. Finally, it has poor adaptability. In a complex electromagnetic environment, the traditional grounding detection method is prone to interference, leading to misjudgment or missed judgment, affecting device reliability.

[0026] To solve the above problems, the embodiment provides a grounding detection system for a handheld welding device, which cooperates through strong current connection and signal transmission to improve the grounding detection accuracy and efficiency of the welding device, automatically alarms and cuts off the circuit, ensures the safety of the operator, and reduces the risk of equipment damage.

[0027] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the present application.

[0028] Please refer to Figure 1 Fig. 1 is a schematic diagram of a grounding detection system for a handheld welding device in a specific embodiment, which includes a strong current connection interface JP1 and a signal transmission interface CN1; The strong current connection interface JP1 is connected with the live wire L, the neutral wire N and the protective earth wire PE of the handheld welding device 1, and the signal transmission interface CN1 is connected with the control board 2 of the handheld welding device 1; The signal transmission interface CN1 is connected with a grounding detection sampling unit 3 and a detection control unit 4; The grounding detection sampling unit 3 forms a detection circuit with the strong current connection interface JP1 and the signal transmission interface CN1; The control board 2 of the handheld welding device 1 controls the on-off of the detection circuit through the detection control unit 4, detects the grounding resistance of the handheld welding device 1 through the grounding detection sampling unit 3, and alarms and cuts off the detection circuit when the grounding resistance exceeds the configured grounding resistance threshold; The strong current connection interface realizes connection with the strong current part of the handheld welding device, ensures the normal establishment of the detection circuit, and provides a basis for the detection of the grounding resistance; The signal transmission interface establishes communication with the control panel of the handheld welding device, so that control signals and detection signals can be quickly and accurately transmitted, ensuring the real-time performance and accuracy of the detection system. The ground detection sampling unit can accurately collect the current signal in the detection loop and convert it into a voltage signal for analysis by the control panel, which is a key component for implementing ground resistance detection and improves detection accuracy. The detection control unit controls the on-off of the detection loop, ensuring that the detection loop can be started and stopped flexibly during the detection process, and the loop can be cut off in time when there is an abnormal ground, ensuring the safety of the operator and the equipment.

[0029] The embodiment realizes accurate detection and control of the ground resistance through the cooperative work of the strong current connection interface, the signal transmission interface, the ground detection sampling unit, and the detection control unit, improving the safety and reliability of the handheld welding device.

[0030] Further, as a refinement and extension of the above embodiment, in order to fully describe the specific implementation process in this embodiment, another ground detection system for a handheld welding device is provided, which includes a strong current connection interface JP1 and a signal transmission interface CN1. The strong current connection interface JP1 is connected with the phase line L, the zero line N, and the protective ground line PE of the handheld welding device 1, and the signal transmission interface CN1 is connected with the control panel 2 of the handheld welding device 1. The signal transmission interface CN1 is connected with the ground detection sampling unit 3 and the detection control unit 4. The ground detection sampling unit 3 forms a detection loop with the strong current connection interface JP1 and the signal transmission interface CN1. The control panel 2 of the handheld welding device 1 controls the on-off of the detection loop through the detection control unit 4, detects the ground resistance of the handheld welding device 1 through the ground detection sampling unit 3, and alarms and cuts off the detection loop when the ground resistance exceeds the configured ground resistance threshold. As shown in Figure 2 The signal transmission interface CN1 adopts a four-core signal line interface, including a power terminal, a ground terminal, a sampling signal terminal, and a detection control terminal. The strong current connection interface JP1 is provided with a phase line terminal, a zero line terminal, and a ground line terminal, the phase line terminal is connected with the phase line of the handheld welding device 1, the zero line terminal is connected with the zero line of the handheld welding device 1, and the protective ground line terminal is connected with the protective ground line of the handheld welding device 1. The detection control unit 4 includes a relay RYL1, a triode Q1, and a diode D1. The relay RYL1 includes a control coil and a controlled normally open switch. The base of the triode Q1 is connected with the resistor R1 and the resistor R2, the other end of the resistor R1 is connected with the detection control end of the signal transmission interface CN1, the other end of the resistor R2 is connected with the emitter of the triode Q1 and grounded; The first end of the control coil of the relay RYL1 is connected with the negative electrode of the diode D1 and the power terminal of the signal transmission interface CN1, the power terminal is connected with the power supply of the controlled board 2 of the handheld welding device 1; Exemplarily, the power supply of the controlled board 2 adopts 3.3V; The second end of the control coil of the relay RYL1 is connected with the positive electrode of the diode D1 and the collector of the triode Q1; The controlled normally open switch of the relay RYL1 is arranged in the detection loop; The ground terminal of the signal transmission interface CN1 is grounded; The ground detection sampling unit 3 comprises the current transformer L1, the diode D2 and the voltage stabilizing diode D3; The current transformer L1 is provided with a strong current side and a weak current side; The first end of the strong current side is connected with the resistor R8, the other end of the resistor R8 is connected with the first end of the controlled normally open switch of the relay RYL1, the second end of the controlled normally open switch of the relay RYL1 is connected with the resistor R4 and the resistor R7; The other end of the resistor R4 is connected with the phase line end of the strong current connection interface JP1, the other end of the resistor R7 is connected with the zero line end of the strong current connection interface JP1; The second end of the strong current side is connected with the ground line end of the strong current connection interface JP1; The first end of the weak current side is connected with the resistor R6 and the positive electrode of the diode D2, the other end of the resistor R6 is connected with the second end of the weak current side and grounded; The negative electrode of the diode D2 is connected with the resistor R3, the other end of the resistor R3 is connected with the resistor R5, the capacitor C1 and the negative electrode of the voltage stabilizing diode D3 and the sampling signal end of the signal transmission interface CN1; The other end of the resistor R5 is connected with the other end of the capacitor C3 and the positive electrode of the voltage stabilizing diode D3 and grounded.

[0031] As Figure 3 shown, the following is an embodiment of the use method of the ground detection system of the handheld welding device provided by the embodiment of the present disclosure, which belongs to the same inventive concept as the ground detection system of the handheld welding device in each of the above embodiments, and the details not described in the embodiment of the ground detection system of the handheld welding device can be referred to the above embodiment of the use method of the ground detection system of the handheld welding device.

[0032] The method comprises the following steps: S1. connect the strong current connection interface with the phase line, zero line and protective ground line of the handheld welding device, and connect the signal transmission interface with the control board of the handheld welding device; S2. power on the handheld welding device, and initialize the sampling signal end and detection control end connected by the signal transmission interface by the control board of the handheld welding device, configure the ground resistance threshold value and the sampling frequency of the sampling signal end; S3. send a signal to the detection control unit through the detection control end of the signal transmission interface by the control board of the handheld welding device, close the detection loop, collect the detection loop current by the ground detection sampling unit, and calculate the ground resistance value according to the detection loop current; S4. determine whether the calculated ground resistance value is less than the configured ground resistance threshold value by the control board of the handheld welding device; If yes, go to step S6; If no, determine that the ground of the handheld welding device is normal, and go to step S5; S5. repeat the steps of steps S3-S4 according to the set detection period to perform ground detection; S6. determine that the ground of the handheld welding device is abnormal, disconnect the detection loop through the detection control unit, and perform ground abnormality alarm.

[0033] The embodiment realizes the process from system connection, initialization, detection to alarm, ensures real-time monitoring and timely processing of the ground state of the handheld welding device, and improves the safety and operation efficiency of the device.

[0034] Further, as a refinement and expansion of the above embodiment, in order to completely describe the specific implementation process in the embodiment, another use method of the ground detection system of the handheld welding device is provided, which includes the following steps: S1. connect the strong current connection interface with the phase line, zero line and protective ground line of the handheld welding device, and connect the signal transmission interface with the control board of the handheld welding device; S2. power on the handheld welding device, and initialize the sampling signal end and detection control end connected by the signal transmission interface by the control board of the handheld welding device, configure the ground resistance threshold value and the sampling frequency of the sampling signal end; the specific steps of step S2 are as follows: S21. the control board of the handheld welding device pre-stores a scene-resistance threshold mapping table, and the scene-resistance threshold mapping table contains the ground resistance threshold values corresponding to different application scenarios; Exemplarily, the application scenarios of the handheld welding device include: a general industrial environment, corresponding to a ground resistance threshold value ≤ 4Ω; a high interference environment, corresponding to a ground resistance threshold value ≤ 2Ω; a precision welding scenario, corresponding to a ground resistance threshold value ≤ 1Ω; S22. Receiving the application scenario selected by the user, loading the corresponding grounding resistance threshold value from the scenario-resistance threshold value mapping table For example, the user selects the "high interference environment" scenario through the operation interface of the handheld welding device, and the control board loads the corresponding grounding resistance threshold value ≤ 2Ω from the scenario-resistance threshold value mapping table; S23. Calculating the reference voltage according to the circuit parameters of the grounding detection sampling unit, and calculating the grounding resistance threshold value according to the reference voltage The corresponding voltage threshold value , and then converting the voltage threshold value into an alarm digital quantity threshold value ; The specific steps of step S23 are as follows: S231. Obtaining the turns ratio n of the current transformer L1 coil, Obtaining the resistance value of the resistor R8, denoted as R8; Obtaining the resistance value of the resistor R6, denoted as R6; For example, the turns ratio n of the current transformer L1 coil is 1:1, the resistance R8 is 100Ω, and the resistance R6 is 10Ω; S232. Marking the output voltage of the weak current side of the grounding detection sampling unit as the actual output voltage, denoted as Marking the output voltage of the weak current side of the grounding detection sampling unit as the actual output voltage, denoted as

[0035]

[0036] wherein, is the loop current of the high-voltage side of the grounding detection sampling unit, is the equivalent voltage of the high-voltage side of the grounding detection sampling unit, is the protective ground voltage; S233. Setting the actual output voltage corresponding to the grounding resistance of 0 as the reference voltage S234. Corresponding to the reference grounding resistance value , calculating the grounding resistance threshold value corresponding to the voltage threshold value ;

[0037] ​​​​​​​Exemplarily, the reference ground resistance value is set in the relevant standard ; S235. According to the ADC bit number d of the control board of the handheld welding device and the power voltage VCC, the voltage threshold value is converted into an alarm digital quantity threshold value ; ; ; S24. Receive the sampling frequency f configured by the user; Exemplarily, the user configures the sampling frequency f as 2000 Hz, that is, 2000 samples per second; S3. The control board of the handheld welding device sends a signal to the detection control unit through the detection control end of the signal transmission interface, closes the detection loop, and collects the detection loop current through the ground detection sampling unit, and calculates the ground resistance value according to the detection loop current; The specific steps of step S3 are as follows: S31. The control board of the handheld welding device controls the triode Q1 to close through the detection control end of the signal transmission interface, thereby controlling the relay RYL1 to close the high-voltage side of the detection loop, and starting sampling; S32. The high-voltage side of the detection loop generates a loop current , and the low-voltage side of the detection loop generates a current , and the voltage value generated by the resistor R6 is rectified by the diode D2 and stabilized by the voltage stabilizing diode D3, and an output voltage is generated;

[0038] Wherein, n is the number of turns ratio of the current transformer L1; S33. The control board of the handheld welding device collects the output voltage according to the set sampling frequency through the sampling signal end of the signal transmission interface, and converts it into a digital quantity until the set sampling number is met, and then averages the sampled digital quantity to obtain a digital quantity average value ; S4. The control board of the handheld welding device judges whether the calculated ground resistance value is less than the configured ground resistance threshold value; If yes, go to step S6; If no, it is determined that the handheld welding device is grounded normally, and go to step S5; In step S4, the control board of the handheld welding device compares the digital quantity average value with the alarm digital quantity threshold value ; If , go to step S6; If , it is determined that the handheld welding device is grounded normally, and go to step S5; S5. Repeat the steps of S3-S4 according to the set detection period to perform the ground detection; The step S5 is specifically as follows: S51. Obtain the set detection period, and determine whether the detection time is reached; If yes, go to step S52; If no, wait for the set time period, and return to step S51; S52. Perform the steps of S3-S4 to perform the ground detection; S6. Determine that the handheld welding device has a ground abnormality, disconnect the detection circuit through the detection control unit, and perform the ground abnormality alarm; the step S6 is specifically as follows: S61. The control board of the handheld welding device outputs a low-level signal through the detection control end, so that the transistor Q1 is cut off, the relay RLY1 is disconnected, and the detection circuit is cut off; S62. Generate the ground abnormality alarm information and write it into the system memory, trigger the audible and light alarm, and perform the alarm display through the display screen of the handheld welding device; S63. Lock the welding function of the handheld welding device, generate the fault log, and until the manual reset and the ground fault is eliminated.

[0039] It should be understood that the size of the serial number of each step in the above embodiments does not mean the order of execution, and the execution order of each process should be determined according to its function and internal logic, and should not constitute any limitation on the implementation process of the embodiments of the present application.

[0040] The above description of the disclosed embodiments enables a person skilled in the art to implement or use the present application. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to these embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A grounding detection system for handheld welding equipment, characterized in that: Including strong electric connection interface and signal transmission interface; The strong current connection interface is connected to the phase line, neutral line and protective ground line of the handheld welding device, and the signal transmission interface is connected to the control panel of the handheld welding device; The signal transmission interface is connected to a ground detection sampling unit and a detection control unit; The ground detection sampling unit forms a detection loop with the strong current connection interface and the signal transmission interface; The control panel of the handheld welding device controls the on / off of the detection circuit through the detection control unit, and detects the grounding resistance of the handheld welding device through the grounding detection sampling unit. When the grounding resistance exceeds the configured grounding resistance threshold, an alarm is issued and the detection circuit is cut off.

2. The grounding detection system for handheld welding equipment according to claim 1, characterized in that: The signal transmission interface adopts a four-core signal line interface, including power terminal, ground terminal, sampling signal terminal and detection control terminal; The strong current connection interface is provided with a phase line terminal, a neutral line terminal and a ground line terminal. The phase line terminal is connected to the phase line of the handheld welding device, the neutral line terminal is connected to the neutral line of the handheld welding device, and the protective ground line terminal is connected to the protective ground line of the handheld welding device.

3. The grounding detection system for handheld welding equipment according to claim 2, characterized in that: The detection control unit includes a relay RYL1, a transistor Q1 and a diode D1; Relay RYL1 includes a control coil and a controlled normally open switch; The base of the transistor Q1 is connected to a resistor R1 and a resistor R2, the other end of the resistor R1 is connected to the detection control terminal of the signal transmission interface, and the other end of the resistor R2 is connected to the emitter of the transistor Q1 and grounded; The first end of the control coil of the relay RYL1 is connected to the cathode of the diode D1 and the power terminal of the signal transmission interface, and the power terminal is connected to the power supply of the controlled board of the handheld welding equipment; The second end of the control coil of relay RYL1 is connected to the anode of diode D1 and the collector of transistor Q1; The controlled normally open switch of relay RYL1 is set in the detection circuit; The ground terminal of the signal transmission interface is grounded.

4. The ground detection system for handheld welding equipment according to claim 3, characterized in that: The ground detection sampling unit includes a current transformer L1, a diode D2 and a voltage stabilizing diode D3; The current transformer L1 is provided with a strong current side and a weak current side; The first end of the strong current side is connected to a resistor R8, the other end of the resistor R8 is connected to the first end of the controlled normally open switch of the relay RYL1, and the second end of the controlled normally open switch of the relay RYL1 is connected to the resistor R4 and the resistor R7; The other end of the resistor R4 is connected to the phase line end of the strong current connection interface, and the other end of the resistor R7 is connected to the neutral line end of the strong current connection interface; The second end of the strong current side is connected to the ground end of the strong current connection interface; The first end of the weak current side is connected to a resistor R6 and is connected to the positive electrode of the diode D2. The other end of the resistor R6 is connected to the second end of the weak current side and is grounded. The cathode of diode D2 is connected to resistor R3, the other end of resistor R3 is connected to resistor R5 and capacitor C1, and is connected to the cathode of voltage stabilizing diode D3 and the sampling signal end of the signal transmission interface; The other end of the resistor R5 is connected to the other end of the capacitor C3 and the anode of the voltage stabilizing diode D3 and is grounded.

5. A method for using the ground detection system for a handheld welding device according to any one of claims 1 to 4, characterized in that: The steps include: S1. Connect the strong power connection interface to the phase line, neutral line and protective ground line of the handheld welding device, and connect the signal transmission interface to the control panel of the handheld welding device; S2. The handheld welding device is powered on, and the control board of the handheld welding device initializes the sampling signal end and the detection control end connected to the signal transmission interface, configures the ground resistance threshold and the sampling frequency of the sampling signal end; S3. The control board of the handheld welding device sends a signal to the detection control unit through the signal transmission interface detection control terminal, closing the detection loop, and collecting the detection loop current through the ground detection sampling unit, and calculating the ground resistance value based on the detection loop current; S4. The control panel of the handheld welding device determines whether the calculated ground resistance value is less than the configured ground resistance threshold; If yes, go to step S6; If not, it is determined that the handheld welding device is properly grounded, and the process goes to step S5; S5. Repeat steps S3-S4 according to the set detection cycle for ground detection; S6. Determine that the handheld welding equipment is grounded abnormally, disconnect the detection circuit through the detection control unit, and issue a grounding abnormality alarm.

6. The method for using the ground detection system for handheld welding equipment according to claim 5, characterized in that: The specific steps of step S2 are as follows: S21. The control board of the handheld welding device is pre-stored with a scene-resistance threshold mapping table, which contains ground resistance thresholds corresponding to different application scenarios; S22. Receive the application scenario selected by the user and load the corresponding ground resistance threshold from the scenario-resistance threshold mapping table ; S23. Calculate the reference voltage based on the circuit parameters of the ground detection sampling unit, and then calculate the ground resistance threshold based on the reference voltage Corresponding voltage threshold , and then the voltage threshold Converted into alarm digital threshold ; S24. Receive the sampling frequency f configured by the user.

7. The method of use according to claim 6, characterized in that: The specific steps of step S23 are as follows: S231. Obtain the turns ratio n of the current transformer L1 coil, ; Get the resistance value of resistor R8, recorded as R8; Get the resistance value of resistor R6, recorded as R6; S232. Mark the output voltage of the weak-current side of the ground detection sampling unit as the actual output voltage, marked as ; The output voltage of the weak-current side of the ground detection sampling unit is marked as the actual output voltage, marked as ; in, For the loop current on the high voltage side of the ground detection sampling unit, It is the equivalent voltage on the high voltage side of the ground detection sampling reference. is the protective earth voltage; S233. Set the grounding resistance to 0 The corresponding actual output voltage is the reference voltage ; S234. Set the reference voltage and reference ground resistance value Correspondingly, calculate the ground resistance threshold Corresponding voltage threshold ; S235. According to the ADC bit d of the control board of the handheld welding device and the power supply voltage VCC, the voltage threshold Converted into alarm digital threshold ; 。 8. The method of use according to claim 5, characterized in that: The specific steps of step S3 are as follows: S31. The control board of the handheld welding device controls the transistor Q1 to be closed through the detection control terminal of the signal transmission interface, thereby controlling the relay RYL1 to close the high-voltage side of the detection loop and start sampling; S32. Detect the loop current generated by the high voltage side of the loop , and then detect the current generated on the low voltage side of the circuit The voltage generated by resistor R6 is rectified by diode D2 and stabilized by Zener diode D3 to generate the output voltage ; Where n is the turns ratio of the current transformer L1; S33. The control board of the handheld welding equipment collects the output voltage according to the set sampling frequency through the sampling signal end of the signal transmission interface , and convert it into digital quantity until the set sampling times are met, and then average the sampled digital quantities to obtain the digital value average value .

9. The method of use according to claim 8, characterized in that: In step S4, the control board of the handheld welding device compares the digital value average with the Alarm digital threshold Make a comparison; like , proceed to step S6; like , determine that the handheld welding equipment is grounded normally, and go to step S5; The specific steps of step S5 are as follows: S51. Get the set detection cycle and determine whether the detection time has been reached; If yes, go to step S52; If not, wait for the set time period and return to step S51; S52. Execute steps S3-S4 to perform ground detection.

10. The method of use according to claim 9, characterized in that: The specific steps of step S6 are as follows: S61. The control board of the handheld welding device outputs a low-level signal through the detection control terminal, turning off transistor Q1 and disconnecting relay RLY1, thus cutting off the detection circuit; S62. Generates grounding abnormality alarm information and writes it to the system memory, triggers an audible and visual alarm, and displays the alarm on the display of the handheld welding device; S63. Lock the welding function of the handheld welding device and generate a fault log until it is manually reset and the ground fault is eliminated.

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