Method and device for monitoring the stability of spiral bevel gear induction heating systems

Abstract

This invention provides a method and device for monitoring the stability of an induction heating system for spiral bevel gears. The method uses an infrared temperature sensor to measure the heating temperature of the gear teeth region, evaluates the uniformity of the tooth surface temperature by calculating the variance of the heating temperature, and analyzes the reliability of the process using the Monte Carlo method. Simultaneously, based on temperature cloud maps acquired by a moving infrared camera, a three-dimensional temperature cloud map of the spiral bevel gear tooth surface is established, and the overall heating stability is evaluated based on the proportion of temperature regions. The device uses a fixed infrared camera and an infrared temperature sensor to measure the temperature cloud map of the spiral bevel gear core and the heating temperature of the teeth on the same cross-section, respectively. Based on the actually set safe proportion range and heating temperature, the coolant circulation speed and the induction power supply power are adjusted accordingly. The temperature variance and average value obtained by this invention, as well as the established three-dimensional temperature cloud map, provide a basis for optimizing process parameters and evaluating stability in the induction heating system.

Description

Technical Field

[0001] This invention relates to the field of spiral bevel gear induction heating technology, and in particular to a method and device for monitoring the stability of a spiral bevel gear induction heating system. Background Technology

[0002] Spiral bevel gears are widely used in various machining equipment, aerospace and aircraft manufacturing, etc. Therefore, higher requirements are placed on the production, processing and heat treatment processes of spiral bevel gears. In particular, obtaining a uniform temperature field during the heat treatment process is the key to improving the hardness of spiral bevel gear teeth.

[0003] Induction heating technology exhibits excellent heating effects in the heat treatment of spiral bevel gears. After heat treatment, spiral bevel gears generally require high hardness in the gear teeth and good impact toughness in the core. This is reflected in the heating temperature, where the gear teeth have a high heating temperature and the core has a certain proportion of low-temperature zones. Induction heating can achieve the effect of locally heating the gear teeth in a short time. Therefore, induction heating technology has been increasingly applied to the heating process of spiral bevel gears.

[0004] The main purpose of using induction heating systems to heat spiral bevel gears is to achieve high hardness in the gear teeth and good impact resistance in the core. This requires good heating stability during the induction heating process. However, existing induction heating systems cannot meet these requirements and have many significant problems during use. For example, existing spiral bevel gear induction heating systems do not consider the impact of gear tooth heating on the core toughness, leading to a decrease in core toughness and weakened impact resistance. Furthermore, existing systems lack criteria for evaluating the stability of the heating process, making real-time adjustments based on actual heating results impossible. Finally, existing systems lack actual heating data output during the heating process as a basis for process adjustment and optimization.

[0005] Therefore, in order to solve the above problems, there is an urgent need for a method and device for monitoring the stability of a spiral bevel gear induction heating system. Summary of the Invention

[0006] To address the problems existing in the prior art, this invention provides a method and device for monitoring the stability of a spiral bevel gear induction heating system. By employing a fixed infrared camera and an infrared temperature sensor, the core temperature cloud map and the heating temperature of the teeth at the same cross-section of the spiral bevel gear are measured respectively. Based on the actually set safety ratio range and heating temperature, the induction power supply power and coolant circulation speed are adjusted to control the high-temperature zone in the core within an allowable range and to make the heating temperature of the teeth more uniform, thereby giving the spiral bevel gear good impact toughness and the teeth high hardness. The infrared temperature sensor measures the heating temperature of the tooth area, and the uniformity of the tooth surface temperature is evaluated by calculating the variance of the measured temperature. The Monte Carlo method is used to analyze the reliability of the process, thereby evaluating the stability of the process. Simultaneously, based on the temperature cloud map obtained from the moving infrared camera, a three-dimensional temperature cloud map of the spiral bevel gear tooth surface is established, and the overall heating stability of the gear is evaluated based on the temperature region ratio. The variance and average values ​​of the heating temperature calculated by the monitoring method, as well as the established three-dimensional temperature cloud map, are output to the technical document, thus providing a basis for evaluating process parameter optimization and system stability in the spiral bevel gear induction heating system.

[0007] This invention provides a method for monitoring the stability of a spiral bevel gear induction heating system, the specific implementation steps of which are as follows:

[0008] S1. Induction heating of the spiral bevel gear:

[0009] S11. The spiral bevel gear is transported to the induction heating area by the conveyor belt, and the pressurization pump is started to make the coolant in the cooling water tank circulate in the cooling water jacket through the inlet and outlet pipes.

[0010] S12. Power the induction heating coil with the induction heating power supply, and regulate the lifting motor, the horizontal motor in the lifting platform assembly and the rotating motor in the gear support assembly so that the induction heating coil sweeps across the spiral bevel gear along the tooth direction of the spiral bevel gear at a travel speed V.

[0011] S13. During the induction heating process, a moving infrared camera is used to obtain the temperature cloud map of the heated part at each time step, and an infrared temperature sensor is used to obtain the heating temperature T(a, b, c) of different teeth in the spiral bevel gear at the same horizontal section, where a represents a certain time step, b represents the group, and c represents the specific infrared temperature sensor in the group. A fixed infrared camera is used to obtain the temperature cloud map X directly above the spiral bevel gear.

[0012] S2. Monitor the heating temperature of the spiral bevel gear:

[0013] Set the heating temperature range (Tmin, Tmax), and calculate the average temperature of the heating temperatures T(a, b, 1), …, T(a, b, n) of the teeth of the spiral bevel gear measured at the a-th time step and the b-th group If the average temperature When, increase the power P of the induction heating power supply corresponding to this group. If the average temperature When, reduce the power P of the induction heating power supply corresponding to this group;

[0014] S3. Monitor the core temperature of the spiral bevel gear:

[0015] Set the safe proportion range (Q1, Q2) of the core of the spiral bevel gear, and calculate the proportion q of the high-temperature area of the temperature cloud map X of the spiral bevel gear obtained by the fixed infrared camera. If q < Q1, reduce the pressure of the pressure pump, thereby reducing the coolant circulation speed. If q > Q2, increase the pressure of the pressure pump, thereby increasing the coolant circulation speed;

[0016] S4. Monitor the heating stability of the spiral bevel gear along the tooth direction:

[0017] Calculate the variance S(b, c) of the heating temperatures T(1, b, c), …, T(n, b, c) of the spiral bevel gear measured at all time steps under the c-th infrared temperature sensor in the b-th group. If the variance S(b, c) is the same as the simulation result, perform reliability calculation and sensitivity analysis. If there is an error between the variance S(b, c) and the simulation result, adjust the temperature data of the simulation result according to the error, and perform reliability calculation and sensitivity analysis;

[0018] The reliability calculation is obtained according to the response surface function of the heating temperature variance of the spiral bevel gear in the tooth direction. The expression of the response surface function is as follows:

[0019]

[0020] In the formula, C0, C i And C ij (i = 1, 2,..., NR; j = i,.., NR) are undetermined coefficients respectively; X i , X j And X ij Are all sample points in the random parameter vector;

[0021] The sensitivity analysis is obtained by using the Monte Carlo method and statistical significance test. The expression of the limit state function g(X) in the statistical significance test is as follows:

[0022]

[0023] In the formula, S0 is the allowable temperature uniformity;

[0024] S5. Monitor the heating stability of the spiral bevel gear:

[0025] The three-dimensional temperature cloud map of the spiral bevel gear tooth surface is obtained by using the temperature cloud map acquired by the mobile infrared camera and the three-dimensional model of the spiral bevel gear. The proportion of the three-dimensional temperature cloud map in the heating temperature range (Tmin, Tmax) set in step S2 is calculated to determine the heating stability of the spiral bevel gear.

[0026] Preferably, the moving infrared camera, the infrared temperature sensor, and the induction heating coil travel at the same speed.

[0027] Preferably, in step S2, the adjustment amount of the power supply P of the induction heating power supply is related to... Positive correlation.

[0028] Preferably, in step S13, the time step is determined based on the travel speed V of the induction heating coil; in step S3, the value of the safety ratio interval (Q1, Q2) is determined according to the minimum toughness required by the spiral bevel gear.

[0029] Preferably, in step S5, when there are overlapping areas in the temperature cloud maps acquired by the moving infrared camera at different time steps, the overlapping areas retain the highest temperature of the temperature cloud maps acquired by the moving infrared camera.

[0030] Preferably, in step S4, the influencing factors of the variance of the spiral bevel gear include the power P of the induction heating power supply, the moving speed V of the induction heating coil, and the distance h between the induction heating coil and the spiral bevel gear teeth.

[0031] In another aspect, the present invention provides a monitoring device for monitoring the stability of a spiral bevel gear induction heating system, comprising a conveyor belt, a support, a lifting motor, a lifting platform assembly, an induction heating power supply, an induction heating coil, a temperature monitoring assembly, a gear support assembly, and a fixed infrared camera. The support is located in the middle of the conveyor belt. A first mounting end of the support is connected to a fixed end of the lifting motor. The telescopic end of the lifting motor is connected to a first end of the lifting base plate in the lifting platform assembly. The movable end of the transverse lead screw in the lifting platform assembly is connected to a first end of the induction heating power supply. A second end of the induction heating power supply is connected to the induction heating coil. A first end of the robotic arm in the temperature monitoring assembly and a fixed end of the fixed infrared camera are respectively connected to a second mounting end and a third mounting end of the support. The bottom end of the support base plate in the gear support assembly is connected to the conveying end of the conveyor belt. The lifting platform assembly includes a lifting base plate, a horizontal motor, and a horizontal lead screw. The second end of the lifting base plate is connected to the fixed end of the horizontal motor, and the output end of the horizontal motor is connected to the fixed end of the horizontal lead screw. The temperature monitoring assembly includes a robotic arm, a mobile infrared camera, and an infrared temperature sensor. The second end of the robotic arm is connected to the first end of the mobile infrared camera, and the second end of the mobile infrared camera is connected to the infrared temperature sensor. The gear support assembly includes a support base plate, a rotating motor, a cooling water tank, a pressurizing pump, a water inlet pipe, a gear support base, a cooling water jacket, and a water outlet pipe. The top end of the support base plate is connected to the fixed end of the rotating motor, the output end of the rotating motor is connected to the fixed end of the cooling water tank, the output end of the cooling water tank is connected to the first end of the water inlet pipe via the pressurizing pump, the second end of the water inlet pipe is connected to the first end of the gear support base, the second end of the gear support base is connected to the first end of the cooling water jacket, the second end of the cooling water jacket is provided with a water outlet pipe, and the third end of the cooling water jacket is connected to the spiral bevel gear.

[0032] Preferably, the number of the lifting motor, the lifting platform assembly, the induction heating power supply, the induction heating coil, and the temperature monitoring assembly are equal, and the lifting motor, the lifting platform assembly, and the temperature monitoring assembly are evenly distributed along the circumferential direction of the gear support assembly.

[0033] Compared with the prior art, the present invention has the following advantages:

[0034] 1. The device of the present invention uses a fixed infrared camera and an infrared temperature sensor to measure the core temperature cloud map of the spiral bevel gear and the heating temperature of the teeth at the same cross section, respectively. Based on the actual set safety ratio range and heating temperature, the power of the induction power supply and the circulation speed of the coolant are adjusted to keep the high temperature zone of the core within the allowable range and make the heating temperature of the teeth more uniform, thereby giving the spiral bevel gear good impact toughness and the teeth high hardness.

[0035] This invention employs an infrared temperature sensor to measure the heating temperature of the gear tooth region. It evaluates the uniformity of the surface temperature of the spiral bevel gear teeth by calculating the variance of the measured heating temperature, and uses the Monte Carlo method to analyze the reliability of the process, thereby assessing its stability. Simultaneously, based on temperature cloud maps acquired by a moving infrared camera, a three-dimensional temperature cloud map of the spiral bevel gear tooth surface is established, and the overall heating stability of the spiral bevel gear is evaluated based on the proportion of temperature regions. This invention outputs the calculated variance data, average value, and the established three-dimensional temperature cloud map to technical documents, providing a basis for optimizing process parameters and evaluating system stability in the spiral bevel gear induction heating system.

[0036] 3. The method of this invention outputs the calculated variance data, process reliability, and the established three-dimensional temperature cloud map to the technical documents, providing a basis for optimizing process parameters and evaluating system stability in the spiral bevel gear induction heating system. Attached Figure Description

[0037] Figure 1 This is a flowchart of the method for monitoring the stability of a spiral bevel gear induction heating system according to the present invention;

[0038] Figure 2 This is an overall structural diagram of the device for monitoring the stability of a spiral bevel gear induction heating system according to the present invention;

[0039] Figure 3 This is a front view of the device of the present invention for monitoring the stability of a spiral bevel gear induction heating system;

[0040] Figure 4 This is a structural diagram of a partial component in the device for monitoring the stability of a spiral bevel gear induction heating system according to the present invention;

[0041] Figure 5 This is a diagram showing the installation position of the spiral bevel gear in the device for monitoring the stability of the spiral bevel gear induction heating system of the present invention.

[0042] Figure 6 This is a structural diagram of the gear support assembly in the device for monitoring the stability of a spiral bevel gear induction heating system according to the present invention.

[0043] Key reference numerals:

[0044] 1. Conveyor belt, 2. Support frame, 3. Lifting motor, 4. Lifting platform assembly, 401. Lifting base plate, 402. Horizontal motor, 403. Horizontal lead screw, 5. Induction heating power supply, 6. Induction heating coil, 7. Temperature monitoring assembly, 701. Robotic arm, 702. Moving infrared camera, 703. Infrared temperature sensor, 703. Spiral bevel gear, 8. Gear support assembly, 9. Support base plate, 901. Rotating motor, 902. Cooling water tank, 903. Pressurization pump, 904. Inlet pipe, 905. Gear support base, 906. Cooling water jacket, 907. Outlet pipe, 908. Fixed infrared camera, 10. Detailed Implementation

[0045] To fully describe the technical content, structural features, objectives, and effects of this invention, a detailed description will be provided below in conjunction with the accompanying drawings.

[0046] The method for monitoring the stability of a spiral bevel gear induction heating system according to the present invention is implemented as follows:

[0047] S1. Induction heating is applied to the spiral bevel gear 8;

[0048] S2. Monitor the heating temperature of the spiral bevel gear 8;

[0049] S3. Monitor the core temperature of the spiral bevel gear 8;

[0050] S4. Monitor the heating stability of the spiral bevel gear 8 along the tooth direction;

[0051] S5. Monitor the heating stability of the spiral bevel gear 8.

[0052] In a preferred embodiment of the present invention, the method for monitoring the stability of a spiral bevel gear induction heating system includes the following steps, such as... Figure 1 As shown:

[0053] S1. Induction heating is applied to the spiral bevel gear 8. The specific operation steps include:

[0054] S11. The spiral bevel gear 8 is transported to the induction heating area by the conveyor belt 1, and the pressurization pump 904 is started to make the coolant in the cooling water tank 903 circulate in the cooling water jacket 907 through the inlet pipe 905 and the outlet pipe 908. Specifically, the lifting motor 3, the lifting platform assembly 4, the induction heating power supply 5 and the induction heating coil 6 constitute the induction heating area.

[0055] S12. Power is supplied to the induction heating coil 6 using the induction heating power supply 5, and the lifting motor 3, the horizontal motor 402 in the lifting platform assembly 4 and the rotating motor 902 in the gear support assembly 9 are controlled so that the induction heating coil 6 sweeps across the spiral bevel gear 8 along the tooth direction of the spiral bevel gear 8 at a travel speed V.

[0056] S13. During the induction heating process, by controlling the robotic arm 701, the traveling speeds of the moving infrared camera 702, the infrared temperature sensor 703, and the induction heating coil 6 are made the same. The temperature contour maps Y1, Y2, Y3, and Y4 of the heated part at each time step are obtained using the moving infrared camera 702. The heating temperature T(a, b, c) of different teeth of the spiral bevel gear 8 in the same horizontal section is obtained using the infrared temperature sensor 703, where a represents a certain time step, b represents the group, and c represents the specific infrared temperature sensor within that group. The temperature contour map X directly above the spiral bevel gear 8 is obtained using the fixed infrared camera 10. Specifically, the time step is determined based on the traveling speed V of the induction heating coil 6.

[0057] Repeat step S1 until the spiral bevel gear 8 is heated completely.

[0058] S2. Monitor the heating temperature of the spiral bevel gear 8:

[0059] Set the heating temperature range (Tmin, Tmax), and calculate the average temperature of the heating temperatures T(a, b, 1), …, T(a, b, n) of the teeth of the spiral bevel gear 8 measured at the a-th time step and the b-th group. If the average temperature then increase the power P of the induction heating power supply 5 corresponding to that group. If the average temperature then decrease the power P of the induction heating power supply 5 corresponding to that group.

[0060] Specifically, the adjustment amount of the power P of the induction heating power supply 5 is positively correlated with and its actual functional correspondence is measured by experiments.

[0061] S3. Since the heated high-temperature teeth have the effect of heat transfer, which causes the core temperature of the spiral bevel gear 8 to increase, it is necessary to monitor the core temperature of the spiral bevel gear 8:

[0062] Set the safety ratio range (Q1, Q2) of the core of the spiral bevel gear 8, and demarcate the core area distribution of the spiral bevel gear 8 based on the temperature contour map X obtained by the fixed infrared camera 10. Calculate the ratio q of the high-temperature area of the temperature contour map X of the spiral bevel gear 8 obtained by the fixed infrared camera 10. If q < Q1, then reduce the pressure of the pressure pump 904, thereby reducing the coolant circulation speed. If q > Q2, then increase the pressure of the pressure pump 904, thereby increasing the coolant circulation speed. If q is within the safety ratio range (Q1, Q2), then do not change the pressure of the pressure pump 904, and the coolant circulation speed remains unchanged.

[0063] Furthermore, in order to improve the core temperature safety of the spiral bevel gear 8, the value of the safety ratio range (Q1, Q2) of the spiral bevel gear 8 is determined according to the minimum toughness required by the spiral bevel gear 8.

[0064] S4. Monitor the heating stability of the spiral bevel gear 8 along the tooth direction:

[0065] Calculate the variance S(b,c) of the heating temperatures T(1,b,c), ..., T(n,b,c) of the spiral bevel gear 8 at all time steps measured by the c-th infrared temperature sensor 703 in group b. The magnitude of the variance S(b,c) is used to characterize the uniformity of the heating temperature in the monitored area. If the variance S(b,c) is the same as the simulation result, then reliability calculation and sensitivity analysis for the process parameters are performed. The reliability obtained from the numerical simulation is the reliability of the induction heating process in this area. If there is an error between the variance S(b,c) and the simulation result, then the temperature data of the simulation result is adjusted according to the error, and reliability calculation and sensitivity analysis are performed.

[0066] Similarly, the variance and reliability of the heating temperature measured by other infrared temperature sensors 703 are calculated. Based on the different monitoring areas represented by each reliability, the reliability of the same gear tooth area is grouped together, and the average value of the reliability in the same group is calculated. The heating stability of the gear teeth of the spiral bevel gear 8 is evaluated based on the reliability. The smaller the reliability value, the worse the heating stability. At the same time, the calculated variance data and reliability value are output to the technical documents.

[0067] In a preferred embodiment of the present invention, the factors affecting the variance of the spiral bevel gear 8 include the power P of the induction heating power supply 5, the moving speed v of the induction heating coil 6, and the spacing h between the induction heating coil 6 and the teeth of the spiral bevel gear 8.

[0068] Specifically, the reliability calculation is obtained based on the response surface function of the variance of the heating temperature in the tooth direction of the spiral bevel gear 8. The expression of the response surface function is as follows:

[0069]

[0070] In the formula, C0, C i and C ij (i = 1, 2, ..., NR; j = i, ..., NR) are undetermined coefficients; X i X j and X ij All of them are sample points in a random parameter vector.

[0071] Sensitivity analysis was performed using the Monte Carlo method and statistical significance test. The expression for the limit state function g(X) in the statistical significance test is as follows:

[0072]

[0073] In the formula, S0 is the allowable temperature uniformity.

[0074] S5. Monitor the heating stability of the spiral bevel gear 8:

[0075] The temperature cloud map of the spiral bevel gear 8 is obtained by using the temperature cloud map acquired by the mobile infrared camera 702 and the three-dimensional model of the spiral bevel gear 8. The proportion of the three-dimensional temperature cloud map in the heating temperature range (Tmin, Tmax) set in step S2 is calculated to determine the heating stability of the spiral bevel gear 8. The higher the proportion, the better the overall heating stability of the spiral bevel gear 8. At the same time, the three-dimensional temperature cloud map is output to the technical document.

[0076] Repeat step S5 until all teeth of the spiral bevel gear 8 have been processed.

[0077] Preferably, when there are overlapping areas in the temperature cloud maps acquired by the mobile infrared camera 702 at different time steps, the overlapping areas retain the highest temperature of the temperature cloud maps acquired by the mobile infrared camera 702; the technical documents output in steps S4 and S5 serve as the basis for optimizing process parameters and evaluating system stability in the spiral bevel gear induction heating system.

[0078] A second aspect of the present invention provides an apparatus for monitoring the stability of a spiral bevel gear induction heating system, such as... Figure 2 and Figure 3 As shown, the assembly includes a conveyor belt 1, a support 2, a lifting motor 3, a lifting platform assembly 4, an induction heating power supply 5, an induction heating coil 6, a temperature monitoring assembly 7, a gear support assembly 9, and a fixed infrared camera 10. The support 2 is located in the middle of the conveyor belt 1. The first mounting end of the support 2 is connected to the fixed end of the lifting motor 3. The telescopic end of the lifting motor 3 is connected to the first end of the lifting base plate 401 in the lifting platform assembly 4. The movable end of the transverse lead screw 403 in the lifting platform assembly 4 is connected to the first end of the induction heating power supply 5. The second end of the induction heating power supply 5 is connected to the induction heating coil 6. The first end of the robotic arm 701 in the temperature monitoring assembly 7 and the fixed end of the fixed infrared camera 10 are respectively connected to the second mounting end and the third mounting end of the support 2. The temperature monitoring assembly 7 is located above the induction heating coil 6. The bottom end of the support base plate 901 in the gear support assembly 9 is connected to the conveying end of the conveyor belt 1.

[0079] Lifting platform component 4, such as Figure 4 As shown, the system includes a lifting base plate 401, a horizontal motor 402, and a horizontal lead screw 403. The second end of the lifting base plate 401 is connected to the fixed end of the horizontal motor 402, and the output end of the horizontal motor 402 is connected to the fixed end of the horizontal lead screw 403. A temperature monitoring component 7 is also included. Figure 5As shown, it includes a robotic arm 701, a mobile infrared camera 702, and an infrared temperature sensor 703. The second end of the robotic arm 701 is connected to the first end of the mobile infrared camera 702, and the second end of the mobile infrared camera 702 is connected to the infrared temperature sensor 703.

[0080] Gear support assembly 9, such as Figure 6 As shown, the system includes a support base plate 901, a rotating motor 902, a cooling water tank 903, a booster pump 904, a water inlet pipe 905, a gear support base 906, a cooling water jacket 907, and a water outlet pipe 908. The top of the support base plate 901 is connected to the fixed end of the rotating motor 902. The output end of the rotating motor 902 is connected to the fixed end of the cooling water tank 903. The output end of the cooling water tank 903 is connected to the first end of the water inlet pipe 905 through the booster pump 904. The second end of the water inlet pipe 905 is connected to the first end of the gear support base 906. The second end of the gear support base 906 is connected to the first end of the cooling water jacket 907. The second end of the cooling water jacket 907 is provided with a water outlet pipe 908. The third end of the cooling water jacket 907 is connected to a spiral bevel gear 8. The cooling water jacket 907 is in direct contact with the shaft hole of the spiral bevel gear 8 to transfer heat. The cooling water jacket 907 drives the spiral bevel gear 8 to rotate through a key connection.

[0081] Specifically, the number of lifting motors 3, lifting platform components 4, induction heating power supplies 5, induction heating coils 6, and temperature monitoring components 7 are equal, and they are evenly distributed along the circumference of the gear support component 9. The number of induction heating coils 6 and induction heating power supplies 5 used to heat the spiral bevel gear 8 is set according to actual heating requirements.

[0082] The following describes in further detail a method and device for monitoring the stability of a spiral bevel gear induction heating system according to the present invention, with reference to specific embodiments:

[0083] S1. Induction heating is applied to the spiral bevel gear 8:

[0084] S11. The spiral bevel gear 8 is transported to the induction heating area by the conveyor belt 1, and the pressurization pump 904 is started to make the coolant in the cooling water tank 903 circulate in the cooling water jacket 907 through the inlet pipe 905 and the outlet pipe 908. Specifically, the lifting motor 3, the lifting platform assembly 4, the induction heating power supply 5 and the induction heating coil 6 constitute the induction heating area.

[0085] S12. Power is supplied to the induction heating coil 6 using the induction heating power supply 5, and the lifting motor 3, the horizontal motor 402 in the lifting platform assembly 4 and the rotating motor 902 in the gear support assembly 9 are controlled so that the induction heating coil 6 sweeps across the spiral bevel gear 8 along the tooth direction of the spiral bevel gear 8 at a travel speed V.

[0086] S13. During the induction heating process, by controlling the robotic arm 701, the traveling speeds of the moving infrared camera 702, the infrared temperature sensor 703, and the induction heating coil 6 are made the same. The temperature contour maps Y1, Y2, Y3, and Y4 of the heated part at each time step are obtained using the moving infrared camera 702. The heating temperature T(a, b, c) of different teeth of the helical bevel gear 8 in the same horizontal section is acquired using the infrared temperature sensor 703, where a represents a certain time step, b represents the group number, and c represents the specific infrared temperature sensor within that group. The temperature contour map X directly above the helical bevel gear 8 is obtained using the fixed infrared camera 10. Specifically, the time step is determined based on the traveling speed V of the induction heating coil 6.

[0087] Repeat step S1 until the helical bevel gear 8 is heated completely.

[0088] S2. Monitor the heating temperature of the helical bevel gear 8:

[0089] Set the heating temperature range (Tmin, Tmax), and calculate the average temperature of the measured heating temperatures T(a, b, 1), …, T(a, b, n) of the teeth of the helical bevel gear 8 at the a-th time step and b-th group. If the average temperature then increase the power P of the induction heating power supply 5 corresponding to that group. If the average temperature then decrease the power P of the induction heating power supply 5 corresponding to that group.

[0090] S3. Monitor the core temperature of the helical bevel gear 8:

[0091] Set the safe proportion range (Q1, Q2) of the core of the helical bevel gear 8, and demarcate the core area distribution of the helical bevel gear 8 based on the temperature contour map X obtained by the fixed infrared camera 10. Calculate the proportion q of the high-temperature area in the temperature contour map X of the helical bevel gear 8 obtained by the fixed infrared camera 10. If q < Q1, then reduce the pressure of the pressure pump 904, thereby reducing the coolant circulation speed. If q > Q2, then increase the pressure of the pressure pump 904, thereby increasing the coolant circulation speed. If q is within the safe proportion range (Q1, Q2), then do not change the pressure of the pressure pump 904, and the coolant circulation speed remains unchanged.

[0092] S4. Monitor the heating stability of the helical bevel gear 8 along the tooth direction:

[0093] Calculate the variance S(b,c) of the heating temperatures T(1,b,c), ..., T(n,b,c) of the spiral bevel gear 8 at all time steps measured by the c-th infrared temperature sensor 703 in group b. If the variance S(b,c) is the same as the simulation result, then reliability calculation and sensitivity analysis for the process parameters are performed. The reliability obtained from the numerical simulation is the reliability of the induction heating process in this region. If there is an error between the variance S(b,c) and the simulation result, then the temperature data of the simulation result is adjusted according to the error, and reliability calculation and sensitivity analysis are performed.

[0094] Similarly, the variance and reliability of the heating temperature measured by other infrared temperature sensors 703 are calculated. Based on the different monitoring areas represented by each reliability, the reliability of the same gear tooth area is grouped together, and the average value of the reliability in the same group is calculated. The heating stability of the gear teeth of the spiral bevel gear 8 is evaluated based on the reliability. The smaller the reliability value, the worse the heating stability. At the same time, the calculated variance data and reliability value are output to the technical documents.

[0095] In this specific embodiment, the temperature uniformity of the spiral bevel gear 8 (i.e., the heating temperature variance of the spiral bevel gear 8) is affected by the induction heating process parameters, namely the power P of the induction heating power supply 5, the travel speed V of the induction heating coil 6, and the tooth spacing h between the induction heating coil 6 and the spiral bevel gear 8. All of the above induction heating process parameters are random variables and follow a normal distribution.

[0096] Therefore, when the reliability analysis uses probability levels p1 = 0.01, p2 = 0.50, and p3 = 0.99, according to the central composite sampling method (the number of central composite sampling points is NS = 2), k +2k+1=21), and calculate the sample point values ​​used to prepare the response surface function according to the following formula:

[0097] x s =μ+σΦ -1 (p n ).

[0098] Based on the induction heating process parameters designed using the sample point values, an induction heating process simulation was performed. The temperature uniformity obtained from the simulation was calculated, and the sample point values ​​and corresponding temperature uniformity were recorded in a table. The response surface method was then used to calculate the response surface function of the temperature uniformity, as shown in the following expression:

[0099]

[0100] In the formula, C0, C i and C ij (i = 1, 2, ..., NR; j = i, ..., NR) are undetermined coefficients; X i Xj and X ij All of them are sample points in a random parameter vector.

[0101] The least squares method is used to perform regression analysis on the above random parameter vector and structural response, and the specific expression is as follows:

[0102]

[0103] In the formula, ε is the error term. To minimize the error term, we have:

[0104]

[0105] Solving the above equation yields the estimated values ​​of each coefficient in the response surface function, thus obtaining the response surface function for this specific implementation.

[0106] In this specific implementation, the power P of the induction heating power supply 5, the travel speed V of the induction heating coil 6, and the tooth spacing h between the induction heating coil 6 and the spiral bevel gear 8 are all random input variables, and the limit state function g(X) is used as a random output variable.

[0107] In this specific implementation, the Monte Carlo probabilistic design method is selected, and 5000 Monte Carlo simulations are performed to generate 5000 samples of the function value of g(X). The specific expression of the limit state function g(X) is as follows:

[0108]

[0109] In the formula, S0 is the allowable temperature uniformity; when g(X) < 0, the process scheme is considered to have failed in stability.

[0110] To make the process scheme more stable, sensitivity analysis is performed, which involves changing parameters and optimizing the process scheme.

[0111] In this specific embodiment, there are three parameters related to the temperature uniformity of the spiral bevel gear 8. Which parameter to change and whether the effect of that parameter on the temperature uniformity stability increases or decreases can be determined by calculating the sensitivity of random parameters.

[0112] Sensitivity analysis uses statistical significance tests. Given a significance level α, random input variables can be categorized into those that have a significant effect on g(X) and those that have no significant effect. The significance test assumes that the sensitivity of the random input variable is 0 and calculates its probability. When this probability exceeds the significance level α, the effect of the random input variable is ignored; otherwise, the random input variable is considered to have a significant effect on g(X).

[0113] Therefore, in this specific embodiment, a significance level of α = 25% is adopted, and bar charts and pie charts are used to represent the influence of each random input variable on the limiting state function g(X). The pie chart obtained from the simulation shows the proportional comparison of the sensitivity of each random parameter, and the bar chart shows the degree of influence of each parameter. Moreover, sensitivity can be positive or negative. If the random input variable appears on the positive half of the vertical axis of the bar chart, the sensitivity is positive, indicating that the limiting state function g(X) increases with the increase of the random input variable; if the sensitivity is negative, it indicates that the response g(X) decreases with the increase of the random input variable.

[0114] S5. Monitor the heating stability of the spiral bevel gear 8:

[0115] A three-dimensional model of the spiral bevel gear 8 is established. The temperature cloud maps Y1, Y2, Y3, and Y4 acquired by the moving infrared camera 702 are then reconstructed into the three-dimensional model of the spiral bevel gear. This process is repeated until the heating of the spiral bevel gear 8 is completed, thereby obtaining a three-dimensional temperature cloud map of the tooth surface of the spiral bevel gear 8. Based on the proportion of the temperature in the three-dimensional temperature cloud map that falls within the set heating temperature range (Tmin, Tmax), the overall heating stability of the spiral bevel gear 8 is determined. The higher the proportion, the better the overall heating stability of the gear. At the same time, the three-dimensional temperature cloud map is output to the technical document.

[0116] Repeat step S5 until all teeth of the spiral bevel gear 8 have been processed.

[0117] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. A method for monitoring stability of an induction heating system for spiral bevel gears, characterized in that, The specific implementation steps are: S1, inductively heating the spiral bevel gear: S11, using a conveyor belt to transport the spiral bevel gear to the inductive heating area, and starting the pressure pump to make the cooling liquid in the cooling water tank circulate in the cooling water jacket through the water inlet pipe and the water outlet pipe; S12, using an inductive heating power supply to power the inductive heating coil, and controlling the lifting motor, the horizontal motor in the lifting platform assembly, and the rotating motor in the gear support assembly to make the inductive heating coil sweep the spiral bevel gear at a speed V in the direction of the gear teeth of the spiral bevel gear; S13, during inductive heating, using a mobile infrared camera to obtain a temperature cloud map of the heated part at each time step, using an infrared temperature sensor to obtain the heating temperature T(a, b, c) of different gear teeth in the same horizontal section of the spiral bevel gear, where a represents a certain time step, b represents a group, and c represents a specific infrared temperature sensor in the group, and using a fixed infrared camera to obtain a temperature cloud map X above the spiral bevel gear; S2, monitoring the heating temperature of the spiral bevel gear: Setting a heating temperature range (Tmin, Tmax), and calculating the average temperature of the measured heating temperature T(a, b, 1),..., T(a, b, n) of the gear teeth of the spiral bevel gear at the a time step, b group If the average temperature , then increase the power of the induction heating power corresponding to the group, if the average temperature , then reduce the power of the induction heating power corresponding to the group; S3, monitoring the core temperature of the spiral bevel gear: Set the safe proportion interval (Q1, Q2) of the core of the spiral bevel gear, and calculate the high temperature area proportion q of the temperature cloud map X of the spiral bevel gear obtained by the fixed infrared camera, if q < Q1, then reduce the pressure of the pressure pump, thereby reducing the circulation speed of the cooling liquid, if q > Q2, then increase the pressure of the pressure pump, thereby increasing the circulation speed of the cooling liquid; S4, monitoring the heating stability of the spiral bevel gear in the direction of the gear teeth: Calculate the variance S(b, c) of the heating temperature T(1, b, c), …, T(n, b, c) of the spiral bevel gear at all time steps measured by the bth infrared temperature sensor in the bth group, if the variance S(b, c) is the same as the simulation result, then perform reliability calculation and sensitivity analysis, if the variance S(b, c) has an error from the simulation result, then adjust the temperature data of the simulation result according to the error, and perform reliability calculation and sensitivity analysis; The reliability calculation is obtained according to the response surface function of the heating temperature variance of the spiral bevel gear in the direction of the gear teeth, and the expression of the response surface function is as follows: where Co, C i and C ij are the unknown coefficients; X i , X j and X ij are the sample points in the random parameter vectors; and i = 1, 2,..., NR; j = i,..., NR. The sensitivity analysis is obtained by using the Monte Carlo method and statistical significance test, and the expression of the limit state function g(X) in the statistical significance test is as follows: In the formula, S0 is the allowable temperature uniformity; S5, monitoring the heating stability of the spiral bevel gear: Using the temperature cloud map obtained by the mobile infrared camera and the three-dimensional model of the spiral bevel gear to obtain a three-dimensional temperature cloud map of the gear tooth surface of the spiral bevel gear, and calculating the proportion of the three-dimensional temperature cloud map in the heating temperature interval (Tmin, Tmax) set in step S2 to determine the heating stability of the spiral bevel gear.

2. The method for monitoring stability of an induction heating system for spiral bevel gears according to claim 1, wherein The moving infrared camera, the infrared temperature sensor, and the inductive heating coil have the same speed.

3. The method for monitoring stability of an induction heating system for spiral bevel gears according to claim 1, wherein In step S2, the adjustment amount of the power supply power P of the induction heating power supply is positively correlated with the temperature of the workpiece.

4. The method for monitoring stability of an induction heating system for spiral bevel gears according to claim 1, wherein In step S13, the time step is determined based on the speed V of the inductive heating coil; in step S3, the values of the safe proportion interval (Q1, Q2) are determined according to the minimum toughness required by the spiral bevel gear.

5. The method for monitoring stability of an induction heating system for spiral bevel gears according to claim 1, wherein, In step S5, when the temperature cloud map obtained by the mobile infrared camera has a repeated area at different time steps, the repeated area retains the highest temperature of the temperature cloud map obtained by the mobile infrared camera.

6. The method for monitoring stability of an induction heating system for spiral bevel gears according to claim 1, wherein, In step S4, the influencing factors of the variance of the spiral bevel gear include the power P of the induction heating power supply, the moving speed V of the induction heating coil, and the distance h between the induction heating coil and the spiral bevel gear teeth.

7. A monitoring device for a monitoring method of stability of an induction heating system for spiral bevel gears according to one of claims 1 to 6, characterized in that It comprises a conveyor belt, a support, a lifting motor, a lifting platform assembly, an induction heating power supply, an induction heating coil, a temperature monitoring assembly, a gear support assembly and a fixed infrared camera, the support is located in the middle of the conveyor belt, the first mounting end of the support and the fixed end of the lifting motor are connected, the telescopic end of the lifting motor and the first end of the lifting bottom plate in the lifting platform assembly are connected, the movable end of the transverse lead screw in the lifting platform assembly and the first end of the induction heating power supply are connected, the second end of the induction heating power supply and the induction heating coil are connected, the first end of the mechanical arm in the temperature detection assembly and the fixed end of the fixed infrared camera are respectively connected with the second mounting end and the third mounting end of the support, the bottom end of the support bottom plate in the gear support assembly and the conveying end of the conveyor belt are connected. The lifting platform assembly comprises a lifting bottom plate, a transverse motor and a transverse lead screw, the second end of the lifting bottom plate and the fixed end of the transverse motor are connected, the output end of the transverse motor and the fixed end of the transverse lead screw are connected; the temperature monitoring assembly comprises a mechanical arm, a mobile infrared camera and an infrared temperature sensor, the second end of the mechanical arm and the first end of the mobile infrared camera are connected, the second end of the mobile infrared camera and the infrared temperature sensor are connected; the gear support assembly comprises a support bottom plate, a rotating motor, a cooling water tank, a pressure pump, an inlet pipe, a gear support base, a cooling water jacket and an outlet pipe, the top end of the support bottom plate and the fixed end of the rotating motor are connected, the output end of the rotating motor and the fixed end of the cooling water tank are connected, the output end of the cooling water tank is connected with the first end of the inlet pipe through the pressure pump, the second end of the inlet pipe and the first end of the gear support base are connected, the second end of the gear support base and the first end of the cooling water jacket are connected, the second end of the cooling water jacket is provided with an outlet pipe, and the third end of the cooling water jacket is connected with the spiral bevel gear.

8. A monitoring device for the monitoring method for the stability of an induction heating system for spiral bevel gears according to claim 7, characterized in that The number of the lifting motor, the lifting platform assembly, the induction heating power supply, the induction heating coil and the temperature monitoring assembly is equal, and the lifting motor, the lifting platform assembly and the temperature monitoring assembly are uniformly distributed along the circumferential direction of the gear support assembly.

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