A method and system for high-precision detection of a welding torch protective mirror

Abstract

This invention relates to the field of laser welding torches, specifically disclosing a method and system for high-precision detection of welding torch protective lenses. The method includes the following steps: S1: During the welding process, the ambient temperature and welding torch heat are acquired in real time; S2: Based on the ambient temperature and welding torch heat, the welding torch temperature t is calculated; S3: Based on the temperature threshold H and the temperature t, it is determined whether the welding torch meets the temperature over-limit condition; S4: If the temperature over-limit condition is met, it is detected whether the light emitted by each cladding layer of the welding torch exceeds the normal range; S5: Based on the degree to which the light emitted by each cladding layer exceeds the normal range, it is determined whether the protective lens is burned out. This invention eliminates the interference of ambient temperature on the detection results and improves the accuracy of the detection.

Description

Technical Field

[0001] This application relates to the field of laser welding torches, specifically to a method for high-precision detection of welding torch protective lenses. Background Technology

[0002] Laser welding torches typically contain a protective lens to prevent welding spatter and fumes from entering the torch's optical path, protecting optical components such as the focusing lens and reflector from contamination or damage. However, during prolonged or high-power laser welding operations, the protective lens itself can also suffer localized burn-out due to absorbing laser energy or accumulating spatter. When the protective lens burns out, a burnt spot forms on its surface, and it loses its original smoothness. When the laser light passes through this uneven surface, diffuse reflection occurs. This diffused light is absorbed by the welding torch body and converted into a large amount of heat, causing a rapid rise in the torch's internal temperature. If the burn-out of the protective lens is not detected and welding is not stopped in time, it can easily lead to damage to expensive optical components such as the focusing lens, and even cause safety accidents.

[0003] Currently, the main technology for detecting burnt protective lenses uses temperature detection. A temperature sensor is installed inside the welding torch to monitor the internal temperature in real time, and a fixed temperature threshold (e.g., 50°C or 60°C) is set. When the temperature value detected by the temperature sensor exceeds this fixed threshold, an alarm is triggered, indicating that the protective lens is damaged.

[0004] However, the above-mentioned existing technical solutions have the following drawbacks: This scheme only compares the absolute temperature value with a fixed threshold, ignoring the impact of ambient temperature on the detection results. When the ambient temperature is low, even if the protective lens has burned out, it takes a long time for the temperature inside the welding torch to rise from a low initial value to the fixed alarm threshold, resulting in an alarm delay. During this period, the user may continue welding with the damaged protective lens, causing the heat generated by diffuse reflection to accumulate continuously, thus causing irreversible damage to internal components such as the focusing lens. When the ambient temperature is high, the temperature inside the welding torch may approach or even exceed the preset fixed alarm threshold under normal operating conditions due to factors such as heat generated by normal circuit operation and heat transfer from welding radiation. In this case, the system is very prone to false alarms, forcibly interrupting normal welding operations, affecting equipment availability and user work efficiency. Summary of the Invention

[0005] In view of this, the present invention proposes a method for high-precision inspection of welding torch protective lenses, comprising the following steps: S1: During the welding process, the ambient temperature and the heat of the welding gun are acquired in real time; S2: Calculate the welding torch temperature t based on the ambient temperature and the welding torch heat. S3: Determine whether the welding torch meets the temperature over-limit condition based on the temperature threshold H and the temperature t; S4: If the temperature exceeds the limit, check whether the light of each cladding layer of the welding torch exceeds the normal range. S5: Determine whether the protective lens is burned based on the degree to which the light of each cladding layer exceeds the normal range.

[0006] Furthermore, in step S1, the heat from the welding torch includes: heat Q1 generated by the internal circuitry of the welding torch, heat Q2 radiated from the welding material to the welding torch, heat Q3 scattered from the internal laser to the main body of the welding torch, and heat Q4 dissipated from the welding torch.

[0007] Furthermore, the heat generated by the internal circuit of the welding torch is Q1 = I×U×β1, where I is the welding torch current, U is the welding torch voltage, and β1 is the welding torch electrothermal conversion coefficient constant. The heat radiated from the welding material to the welding torch is Q2 = P×m×β2, where P is the laser output power, m is the reflectivity of the welding material, and β2 is the welding angle correlation coefficient of the welding torch. The heat Q3 scattered by the internal laser onto the welding torch body is given by the formula: Q3 = P × (1 - n), where P is the laser output power and n is the laser transmittance of the optical path.

[0008] Furthermore, in step S2, based on the ambient temperature and the welding torch heat, the welding torch temperature is calculated as follows: , t represents the welding torch temperature, T represents the ambient temperature, and C represents the specific heat capacity coefficient of the welding torch.

[0009] Furthermore, in step S3, determining whether the welding torch meets the temperature exceedance condition based on the temperature threshold H and the temperature t includes: S31: Determine whether t≥H is true. S32: If so, determine whether the welding time exceeds the preset time. S33: If so, determine whether the difference between the current temperature and the temperature before the preset time exceeds the temperature change threshold. S34: If so, then the welding torch is deemed to meet the temperature over-limit condition.

[0010] Furthermore, if t≥H and the welding time of the welding torch does not exceed the preset time, but the difference between the current temperature and the temperature at the start of welding exceeds the temperature change threshold, it is also determined that the welding torch meets the temperature over-limit condition.

[0011] Furthermore, in step S4, detecting whether the light from each cladding layer of the welding torch exceeds the normal range includes: Before the protective lens is burned out, the welding torch is turned on in advance to output laser, the voltage value v0 of each cladding optical path is detected, the output power w0 is obtained, and the optical path calibration constant α=v0 / w0 is calculated. After the temperature exceeds the limit, obtain the voltage value v of the current cladding optical path and determine whether v≥α×w×k is true. If it is true, the cladding light is determined to be out of normal range, where w is the output power of the current cladding optical path and k is the multiplier coefficient.

[0012] Furthermore, in step S4, the optical path of each cladding layer includes: The optical path in front of the protective mirror The optical path between the protective lens and the focusing lens, The optical path between the focusing lens and the end cap The optical path from the end cap to the fiber splice point. For all optical paths, obtain the corresponding voltage value and output power, and calculate the corresponding optical path calibration constant; after the temperature exceeds the limit, based on the corresponding optical path calibration constant, determine whether the cladding light of the optical path exceeds the normal range.

[0013] Furthermore, S5 includes: Based on the degree to which the cladding light in each optical path exceeds the normal range, the damaged optical path is determined, and based on the damaged optical path, it is determined whether the protective lens is burned.

[0014] Accordingly, the present invention also proposes a system for high-precision inspection of welding torch protective lenses, for implementing the above method, comprising: The temperature acquisition module is used to acquire the ambient temperature during the welding process of the welding torch; The heat calculation module is used to calculate the heat generated during the welding process of the welding torch; The temperature calculation module is used to calculate the welding torch temperature t based on the ambient temperature and the welding torch heat. The temperature over-limit judgment module is used to determine whether the welding torch meets the temperature over-limit condition based on the temperature threshold H and the temperature t. The cladding light exceeding the limit judgment module is used to detect whether the cladding light of the welding torch exceeds the normal range after the temperature exceeds the limit. If the cladding light exceeds the normal range, it is determined that the protective lens has burned out.

[0015] This invention calculates the welding torch temperature and compares it to a threshold based on ambient temperature and welding torch heat, rather than directly comparing absolute temperature with a fixed threshold. This eliminates the interference of ambient temperature on the detection results to some extent, preventing delayed alarms at low ambient temperatures and avoiding false alarms due to normal temperature rises at high ambient temperatures. Furthermore, by detecting whether the cladding light in each optical path of the welding torch exceeds the normal range, the accuracy of the detection is improved. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of a method for high-precision detection of welding torch protective mirror according to the present invention; Figure 2 This is a schematic diagram showing the installation position distribution of the photoelectric sensor in one embodiment of the present invention; Figure 3 This is a flowchart of optical path damage detection with multiple sets of multiplier coefficients k in one embodiment of the present invention. Detailed Implementation

[0017] To address the shortcomings of existing protective lens burn-out detection methods that rely on comparing absolute temperature values ​​with fixed thresholds, this invention proposes a highly accurate method for detecting welding torch protective lenses.

[0018] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the various embodiments of this application will be described in detail below with reference to the accompanying drawings. However, those skilled in the art will understand that many technical details have been presented in the various embodiments of this application to enable the reader to better understand this application. However, the technical solutions claimed in this application can be implemented even without these technical details and various changes and modifications based on the following embodiments.

[0019] In the following description, certain specific details are set forth for the purpose of illustrating various disclosed embodiments in order to provide a thorough understanding of the various disclosed embodiments. However, those skilled in the art will recognize that embodiments may be practiced without one or more of these specific details. In other instances, well-known apparatuses, structures, and techniques associated with this application may not have been shown or described in detail to avoid unnecessarily obscuring the description of the embodiments.

[0020] Unless the context requires otherwise, throughout the specification and claims, the word “comprising” and its variations, such as “including” and “having”, shall be understood to have an open, inclusive meaning, that is, to be interpreted as “including, but not limited to”.

[0021] The embodiments of this application will be described in detail below with reference to the accompanying drawings to provide a clearer understanding of the purpose, features, and advantages of this application. It should be understood that the embodiments shown in the drawings are not intended to limit the scope of this application, but are merely for illustrating the essential spirit of the technical solution of this application.

[0022] Throughout this specification, references to "an embodiment" or "an embodiment" indicate that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment. Therefore, the appearance of "in an embodiment" or "an embodiment" in various places throughout the specification does not necessarily refer to the same embodiment. Furthermore, a particular feature, structure, or characteristic may be combined in any manner in one or more embodiments.

[0023] This invention proposes a method for high-precision inspection of welding torch protective lenses, such as... Figure 1 As shown, it includes the following steps: S1: During the welding process, the ambient temperature and the heat of the welding gun are acquired in real time; S2: Calculate the welding torch temperature t based on the ambient temperature and the welding torch heat. The welding torch temperature t refers to the reference value of the internal temperature of the welding torch without considering abnormal factors such as the burning of the protective lens; S3: Determine whether the welding torch meets the temperature over-limit condition based on the temperature threshold H and the temperature t; The temperature threshold H is a preset judgment benchmark value used to measure whether the current temperature is abnormally high. When the temperature t satisfies the preset relationship with the temperature threshold H, the welding torch is judged to meet the temperature over-limit condition. S4: If the temperature exceeds the limit, check whether the light of each cladding layer of the welding torch exceeds the normal range. Cladding light detection is achieved by photoelectric sensors arranged at various optical path positions inside the welding torch. Each photoelectric sensor detects the cladding light intensity at the corresponding position in real time and converts it into a voltage value. This voltage value is compared with the reference value under normal conditions to determine whether the cladding light exceeds the normal range. S5: Determine whether the protective lens is burned based on the degree to which the light of each cladding layer exceeds the normal range.

[0024] When the protective lens burns out, the laser light passing through the uneven surface of the lens undergoes diffuse reflection, causing varying degrees of abnormal increases in the cladding light intensity at different locations within the welding torch's optical path. Therefore, by analyzing the degree to which the cladding light exceeds the normal range, it can be determined whether the protective lens has burned out. By first determining the temperature exceedance and then the cladding light anomaly, the detection method avoids the problem of false alarms or missed alarms caused by the susceptibility of single temperature threshold determination to ambient temperature interference, significantly improving the accuracy of protective lens burnout detection.

[0025] Furthermore, the welding torch heat in step S1 specifically includes the following four parts.

[0026] The first part is the heat Q1 generated by the internal circuit of the welding torch. This part of the heat comes from the heat energy generated by the power loss of the internal circuit of the welding torch during operation, such as the Joule heat generated by the drive circuit and control circuit during operation.

[0027] Q1 = I×U×β1, where I is the welding torch current, U is the welding torch voltage, and β1 is the welding torch electrothermal conversion coefficient constant, which represents the efficiency of the circuit in converting electrical energy into heat energy. It can be obtained by testing and calibration before the welding torch leaves the factory, and the typical value is 0.1.

[0028] The second part is the heat Q2 radiated from the welding material to the welding torch. During the laser welding process, after the laser irradiates the surface of the welding material, some of the laser energy is absorbed by the material, and the material will radiate heat to the surroundings. The heat radiated towards the welding torch is Q2. This part of the heat is related to the type of welding material and its surface condition.

[0029] Q2 = P×m×β2, where P is the laser output power, m is the reflectivity of the welding material, which varies depending on the material. For example, the reflectivity of low-reflectivity materials such as carbon steel and stainless steel is about 20% to 40%, while the reflectivity of high-reflectivity materials such as aluminum and copper is about 80% to 95%. β2 is the welding angle correlation coefficient of the welding torch, which is related to the tilt angle of the welding torch relative to the workpiece. It can be determined by thermal simulation or experiment during the design of the welding torch, and the typical value is 0.02.

[0030] The third part is the heat Q3 caused by the internal laser scattering to the welding torch body. During the optical path transmission of the laser inside the welding torch, due to incomplete transmission of optical components and abnormal conditions such as burnt-out protective mirrors, some laser light will be scattered and absorbed by the welding torch body and converted into heat. This part of the heat reflects the loss of optical path transmission.

[0031] Q3 = P × (1-n), where P is the laser output power and n is the laser transmittance of the optical path. When the optical path is normal, the typical value of n is 96%. When the protective lens is burned out, n will drop significantly to about 10%, at which point the heat scattered to the welding torch body will increase significantly.

[0032] The fourth part is the heat dissipated by the welding torch, Q4, which is the heat lost by the welding torch to the surrounding environment through its outer shell surface. The heat dissipated by the welding torch, Q4, is calculated based on the effective thermal power through the law of conservation of energy. Specifically, Q4 depends on the heat dissipation area of ​​the welding torch shell, the surface heat transfer coefficient, and the temperature difference between the welding torch surface and the environment. Given a fixed welding torch structure, Q4 can be regarded as a function value related to the current temperature, or it can be treated as a preset constant under specific working conditions and obtained through testing and calibration before the welding torch leaves the factory.

[0033] By dividing the heat of the welding torch into the four components mentioned above, the heat source and distribution inside the welding torch can be comprehensively and accurately reflected, providing a reliable data basis for subsequent temperature calculations.

[0034] Based on the ambient temperature and the heat of the welding torch, the welding torch temperature is calculated as follows: , t represents the welding torch temperature, T represents the ambient temperature, and C represents the specific heat capacity coefficient of the welding torch. The above formula eliminates the influence of ambient temperature fluctuations on the test results.

[0035] Furthermore, in step S3, determining whether the welding torch meets the temperature exceedance condition based on the temperature threshold H and the temperature t includes: S31: Determine whether t≥H is true. If t ≥ H is true, it means that the temperature of the welding torch has reached or exceeded the judgment benchmark value. At this time, it is necessary to further analyze the dynamic change trend of the temperature to rule out the normal temperature rise. Therefore, step S32 is executed. S32: If yes, determine whether the welding time exceeds the preset time. The preset time is a pre-set time length, such as one minute, used to distinguish between the initial stage of welding and the continuous stage of welding. If the welding time exceeds the preset time, proceed to step S33. S33: If yes, determine whether the difference between the current temperature and the temperature before the preset time exceeds the temperature change threshold; if the difference exceeds the preset temperature change threshold, it indicates that the internal temperature of the welding torch has risen rapidly in the recent period, and this rapid temperature rise is usually caused by diffuse reflection heat generated by the burnout of the protective lens. S34: If so, the welding torch is deemed to have exceeded the temperature limit. By introducing the determination of the temperature change rate, the sudden temperature rise caused by the burnt-out protective lens is effectively distinguished from the slow temperature rise during normal welding, further improving the accuracy of the detection.

[0036] Furthermore, the present invention also provides another scenario where the temperature exceeds the limit. If the condition of t≥H is met in step S31, and the welding time of the welding torch has not exceeded the preset time, it is not possible to compare the temperature difference with that before the preset time. Instead, it is determined whether the difference between the current temperature and the temperature at the start of welding exceeds the temperature change threshold.

[0037] If the difference exceeds the temperature change threshold, meaning a significant temperature rise occurs shortly after welding begins, it indicates an abnormal heat source inside the welding torch. In this case, the welding torch is also deemed to meet the temperature over-limit condition. This setting considers the scenario where the protective lens burns out early in the welding process. In this case, the welding torch temperature rises rapidly from its initial state. Although the welding time is short, the temperature change is sufficient to indicate an abnormality. Therefore, by including this scenario in the temperature over-limit condition judgment range, timely detection of protective lens burnout in the early stages of welding is ensured.

[0038] The specific method for detecting whether the cladding light of the welding torch exceeds the normal range in step S4 is as follows: First, under normal conditions where the protective lens is not burned out, the welding torch is pre-activated to output laser light. That is, during factory calibration or periodic calibration of the welding torch, the welding torch is started and laser light is output at a known power after confirming that the protective lens is intact. In this state, the voltage value v0 of each cladding light path is detected, and the current output power w0 is obtained. Then, the optical path calibration constant α is calculated according to the formula α = v0 / w0. The calibration constant α reflects the cladding light detection voltage value corresponding to a unit laser output power under normal optical path conditions.

[0039] After the temperature exceeds the limit, the voltage value v of the current cladding optical path is obtained, along with the current output power w of that path. Then, the inequality v ≥ α × w × k is checked, where k is a multiplier. If the inequality holds, the cladding light in that path is determined to be outside the normal range. The multiplier k is a value greater than 1, used to set the sensitivity for detecting cladding light anomalies. When the cladding light intensity reaches several times the normal level, it indicates abnormal diffuse reflection in the optical path, usually caused by damage to the protective lens or other optical components.

[0040] By pre-calibrating and comparing in real time, abnormal increases in cladding light intensity can be accurately identified.

[0041] Furthermore, the optical path of each cladding layer specifically includes the following four locations, as shown in the reference. Figure 2 The mounting location of the photoelectric sensor in one embodiment.

[0042] The first position is the optical path in front of the protective mirror. The photoelectric sensor PD1 at this position is used to monitor the intensity of diffuse reflected light generated when the protective mirror malfunctions.

[0043] The second location is the optical path between the protective lens and the focusing lens. The photoelectric sensor PD2 at this location is used to monitor the intensity of diffuse reflected light generated when the protective lens and the focusing lens malfunction.

[0044] The third location is the optical path between the focusing lens and the end cap. The photoelectric sensor PD3 at this location is used to monitor the intensity of diffuse reflected light generated when the focusing lens, mirror, and end cap malfunction.

[0045] The fourth position is the optical path from the end cap to the fiber optic splice point. The photoelectric sensor PD4 at this position is used to monitor the cladding light passing through the optical path and reflect the backlight situation of the entire welding torch.

[0046] For all the aforementioned optical paths, the voltage and output power corresponding to each path are acquired, and the optical path calibration constant for each path is calculated. After the temperature exceeds the limit, based on the optical path calibration constant and the currently detected voltage and output power, it is determined whether the cladding light of each optical path exceeds the normal range. By simultaneously detecting the cladding light at multiple optical path positions, the changes in optical signals at each optical element inside the welding torch can be comprehensively acquired, providing data support for accurately locating damaged components.

[0047] Furthermore, step S5 specifically includes the following: determining the damaged optical path based on the degree to which the cladding light of each optical path exceeds the normal range.

[0048] Specifically, there is a correlation between the degree of abnormal increase in cladding light in different optical paths and the location of the damaged optical element.

[0049] When the protective lens burns out, the laser light diffuses through the uneven surface of the protective lens. The intensity of the cladding light in the optical path in front of the protective lens and between the protective lens and the focusing lens will increase significantly, while the intensity of the cladding light in the optical path between the focusing lens and the end cap will increase relatively little.

[0050] When the focusing lens is damaged, the intensity of the cladding light in the optical path between the focusing lens and the end cap will increase significantly.

[0051] When a reflector or end cap malfunctions, a characteristic cladding light intensity distribution will appear at the corresponding optical path location. Therefore, based on the degree and distribution pattern of the cladding light exceeding the normal range in each optical path, the specific damaged optical path can be identified, and thus, whether the protective mirror has burned out can be determined based on the damaged optical path.

[0052] refer to Figure 3 In one embodiment, different multiplication factors k are set based on four sets of voltage data to obtain specific optical path damage results.

[0053] By comprehensively judging the degree of cladding optical anomalies based on multiple optical paths, the accuracy and reliability of protective mirror burn-out determination are effectively improved.

[0054] Accordingly, the present invention also provides a system for high-precision inspection of welding torch protective mirrors, for performing the above-described method.

[0055] The system includes a temperature acquisition module, a heat calculation module, a temperature calculation module, a temperature over-limit judgment module, and a cladding light over-limit judgment module.

[0056] The temperature acquisition module is used to acquire the ambient temperature during the welding process of the welding torch, which can be achieved through a temperature sensor.

[0057] The heat calculation module is used to calculate the heat generated during the welding process of the welding torch. Specifically, it calculates the heat generated by the internal circuit of the welding torch, the heat radiated from the welding material to the welding torch, the heat scattered from the internal laser to the welding torch body, and the heat dissipated by the welding torch. This module is connected to the current sensor, voltage sensor, and power sensor of the welding torch to obtain the necessary calculation parameters.

[0058] The temperature calculation module is connected to the temperature acquisition module and the heat calculation module respectively, and is used to calculate the welding torch temperature t based on the ambient temperature and the welding torch heat.

[0059] The temperature over-limit judgment module is connected to the temperature calculation module and is used to determine whether the welding torch meets the temperature over-limit conditions based on the temperature threshold H and temperature t.

[0060] The cladding light exceeding the limit judgment module includes a photoelectric sensor and is connected to the temperature exceeding the limit judgment module. It is used to detect whether the cladding light of the welding torch exceeds the normal range after the temperature exceeding the limit condition is met. If the cladding light exceeds the normal range, it is determined that the protective lens has burned out.

[0061] The system's modules work together. First, the temperature acquisition module, heat calculation module, temperature calculation module, and temperature over-limit judgment module perform a preliminary temperature assessment. When an abnormal temperature is detected, the cladding light over-limit judgment module verifies the optical path to accurately determine whether the protective lens is burned out. The specific implementation methods of each module are consistent with the corresponding operations in the steps described above, and will not be repeated here.

[0062] The solutions provided by the embodiments of this application have been described in detail above. The various embodiments in the specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the apparatus disclosed in the embodiments, since it corresponds to the method disclosed in the embodiments, the description is relatively simple; relevant parts can be referred to in the method section. It should be noted that those skilled in the art can make several improvements and modifications to this application without departing from the principles of this application, and these improvements and modifications also fall within the protection scope of the claims of this application.

[0063] Those skilled in the art will further recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0064] The steps of the methods or algorithms described in conjunction with the embodiments disclosed herein can be implemented directly by hardware, a software module executed by a processor, or a combination of both. The software module can be located in random access memory (RAM), main memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium known in the art.

Claims

1. A method for high-precision inspection of welding torch protective lenses, characterized in that, Includes the following steps: S1: During the welding process, the ambient temperature and the heat of the welding gun are acquired in real time; S2: Calculate the welding torch temperature t based on the ambient temperature and the welding torch heat. S3: Determine whether the welding torch meets the temperature over-limit condition based on the temperature threshold H and the temperature t; S4: If the temperature exceeds the limit, check whether the light of each cladding layer of the welding torch exceeds the normal range. S5: Determine whether the protective lens is burned based on the degree to which the light of each cladding layer exceeds the normal range.

2. The method for high-precision inspection of welding torch protective mirrors according to claim 1, characterized in that, In step S1, the heat from the welding torch includes: heat Q1 generated by the internal circuitry of the welding torch, heat Q2 radiated from the welding material to the welding torch, heat Q3 scattered from the internal laser to the main body of the welding torch, and heat Q4 dissipated from the welding torch.

3. The method for high-precision inspection of welding torch protective mirrors according to claim 2, characterized in that, The heat generated by the internal circuit of the welding torch is Q1 = I×U×β1, where I is the welding torch current, U is the welding torch voltage, and β1 is the welding torch electrothermal conversion coefficient constant. The heat radiated from the welding material to the welding torch is Q2 = P×m×β2, where P is the laser output power, m is the reflectivity of the welding material, and β2 is the welding angle correlation coefficient of the welding torch. The heat Q3 scattered by the internal laser onto the welding torch body is given by the formula: Q3 = P × (1 - n), where P is the laser output power and n is the laser transmittance of the optical path.

4. The method for high-precision inspection of welding torch protective mirrors according to claim 2, characterized in that, In step S2, based on the ambient temperature and the welding torch heat, the welding torch temperature is calculated as follows: ， t represents the welding torch temperature, T represents the ambient temperature, and C represents the specific heat capacity coefficient of the welding torch.

5. The method for high-precision inspection of welding torch protective mirrors according to claim 1, characterized in that, In step S3, determining whether the welding torch meets the temperature over-limit condition based on the temperature threshold H and the temperature t includes: S31: Determine whether t≥H is true. S32: If so, determine whether the welding time exceeds the preset time. S33: If so, determine whether the difference between the current temperature and the temperature before the preset time exceeds the temperature change threshold. S34: If so, then the welding torch is deemed to meet the temperature over-limit condition.

6. The method for high-precision inspection of welding torch protective mirrors according to claim 5, characterized in that, If t≥H and the welding time of the welding torch does not exceed the preset time, but the difference between the current temperature and the temperature at the start of welding exceeds the temperature change threshold, the welding torch is also judged to meet the temperature over-limit condition.

7. The method for high-precision inspection of welding torch protective mirrors according to claim 1, characterized in that, In step S4, checking whether the light intensity of each cladding layer of the welding torch exceeds the normal range includes: Before the protective lens is burned out, the welding torch is turned on in advance to output laser, the voltage value v0 of each cladding optical path is detected, the output power w0 is obtained, and the optical path calibration constant α=v0 / w0 is calculated. After the temperature exceeds the limit, obtain the voltage value v of the current cladding optical path and determine whether v≥α×w×k is true. If it is true, the cladding light is determined to be out of normal range, where w is the output power of the current cladding optical path and k is the multiplier coefficient.

8. The method for high-precision inspection of welding torch protective mirrors according to claim 7, characterized in that, In step S4, the optical paths of each cladding layer include: The optical path in front of the protective mirror The optical path between the protective lens and the focusing lens, The optical path between the focusing lens and the end cap The optical path from the end cap to the fiber splice point. For all optical paths, obtain the corresponding voltage value and output power, and calculate the corresponding optical path calibration constant; after the temperature exceeds the limit, based on the corresponding optical path calibration constant, determine whether the cladding light of the optical path exceeds the normal range.

9. The method for high-precision inspection of welding torch protective mirrors according to claim 8, characterized in that, Step S5 includes: Based on the degree to which the cladding light in each optical path exceeds the normal range, the damaged optical path is determined, and based on the damaged optical path, it is determined whether the protective lens is burned.

10. A system for high-precision inspection of welding torch protective lenses, characterized in that, include: The temperature acquisition module is used to acquire the ambient temperature during the welding process of the welding torch; The heat calculation module is used to calculate the heat generated during the welding process of the welding torch; The temperature calculation module is used to calculate the welding torch temperature t based on the ambient temperature and the welding torch heat. The temperature over-limit judgment module is used to determine whether the welding torch meets the temperature over-limit condition based on the temperature threshold H and the temperature t. The cladding light exceeding the limit judgment module is used to detect whether the cladding light of the welding torch exceeds the normal range after the temperature exceeds the limit. If the cladding light exceeds the normal range, it is determined that the protective lens has burned out.

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