Method and device for adjusting light intensity of light beam for welding and laser welding machine

Abstract

The invention relates to the technical field of laser welding, in particular to a light beam intensity adjusting method and device for welding and a laser welding machine. The method comprises the following steps: identifying a processing surface and a processing track of a target product; for each section of processing track, generating a Gaussian beam and preheating at the starting point of the section of processing track; determining a first area and monitoring the temperature of the first area; whether the temperature of the first area reaches the preset temperature or not is judged, and if yes, the Gaussian beam is switched into a flat-topped beam and moves along the section of machining track, so that the target product is machined; determining a second area and a third area before the flat-topped light beam moves; when the flat-topped light beam moves, the second area and the third area are updated in real time, and the light intensity of the flat-topped light beam acting on the target product is adjusted according to the temperature change conditions of the second area and the third area. The problem that a laser welding machine cannot automatically adjust the light intensity of laser is solved.

Description

Technical Field

[0001] The present invention relates to the technical field of laser welding, and in particular, to a method and device for adjusting the light intensity of a light beam for welding and a laser welding machine. Background Art

[0002] A laser welding machine is a device that uses a laser beam with a high energy density as a heat source for welding. It melts the material through the interaction between the laser beam and the material to form a weld seam.

[0003] Currently, for determining the light intensity of the laser of a laser welding machine, generally, the light intensity of the laser that can melt the processing material is first manually adjusted, and then the laser beam corresponding to this light intensity is used to melt the processing material to complete the welding work.

[0004] Doing so, during the entire welding process, the light intensity of the laser is always fixed. For the processing material, there is a protective layer or oxide film on the surface, and the melting temperatures of the surface and the interior of the processing material are inconsistent. Moreover, during the working process, since the laser always acts on the surface of the processing material, the temperature in the area near the laser rises in advance due to the influence of the laser first, and the temperatures of the points on the laser movement trajectory are inconsistent. If a laser with a fixed light intensity is used, then due to the inconsistent temperature, the processing marks will be relatively rough. Therefore, it is unreasonable to use a laser with a fixed light intensity for welding work, and there is a problem that the laser welding machine cannot self-adjust the light intensity of the laser. Summary of the Invention

[0005] Based on this, in view of the above problems, it is necessary to provide a method and device for adjusting the light intensity of a light beam for welding and a laser welding machine.

[0006] An embodiment of the present invention is implemented as follows. A method for adjusting the light intensity of a light beam for welding, the method for adjusting the light intensity of a light beam for welding includes:

[0007] S101, identifying the processing surface of the target product and determining the processing trajectory on each processing surface;

[0008] S102, for each section of the processing trajectory, generating a Gaussian beam according to a preset light intensity, and using the Gaussian beam to preheat at the starting point of this section of the processing trajectory;

[0009] S103, marking the irradiation area formed by the Gaussian beam on the target product as the first area, and monitoring the temperature of the first area;

[0010] S104, determining whether the temperature of the first area reaches a preset temperature. If so, switching the Gaussian beam to a flat-top beam, and using the flat-top beam to move along this section of the processing trajectory to process the target product;

[0011] S105. Before the flat-top beam moves, mark the irradiation area formed by the flat-top beam on the target product as the second area, and determine the next travel area of the flat-top beam based on the second area and this section of the processing trajectory, denoted as the third area;

[0012] S106. When the flat-top beam moves, update the second area and the third area in real time, and adjust the light intensity of the flat-top beam acting on the target product according to the temperature changes in the second area and the third area.

[0013] In one embodiment, the present invention provides a device for adjusting the light intensity of a beam for welding. The device for adjusting the light intensity of a beam for welding includes:

[0014] A trajectory determination module, configured to identify the processing surface of the target product and determine the processing trajectory on each processing surface;

[0015] A first processing module, configured to generate a Gaussian beam according to a preset light intensity for each section of the processing trajectory, and preheat at the starting point of this section of the processing trajectory using the Gaussian beam;

[0016] A temperature detection module, configured to mark the irradiation area formed by the Gaussian beam on the target product as the first area and monitor the temperature of the first area;

[0017] A beam switching module, configured to determine whether the temperature of the first area reaches a preset temperature. If so, switch the Gaussian beam to a flat-top beam, and move along this section of the processing trajectory using the flat-top beam to process the target product;

[0018] An area identification module, configured to, before the flat-top beam moves, mark the irradiation area formed by the flat-top beam on the target product as the second area, and determine the next travel area of the flat-top beam based on the second area and this section of the processing trajectory, denoted as the third area;

[0019] A light intensity adjustment module, configured to, when the flat-top beam moves, update the second area and the third area in real time, and adjust the light intensity of the flat-top beam acting on the target product according to the temperature changes in the second area and the third area.

[0020] In one embodiment, the present invention provides a laser welding machine. The laser welding machine includes a laser emission module, a temperature identification module, a beam shaping module, and a control module;

[0021] The laser emission module is connected to the control module and is configured to generate a Gaussian beam;

[0022] The temperature identification module is connected to the control module and is configured to identify the temperature;

[0023] The beam shaping module is connected to the control module and is used to transform a Gaussian beam into a flat-top beam;

[0024] The control module is used to execute the steps of the method for adjusting the beam intensity for welding as described above.

[0025] A method for adjusting the beam intensity for welding provided by an embodiment of the present invention includes identifying the processing surface of the target product and determining the processing trajectory on each processing surface; for each segment of the processing trajectory, generating a Gaussian beam according to a preset intensity, and using the Gaussian beam to perform preheating at the starting point of the segment of the processing trajectory; marking the irradiation area formed by the Gaussian beam on the target product as the first area, and monitoring the temperature of the first area; judging whether the temperature of the first area reaches a preset temperature, if so, switching the Gaussian beam to a flat-top beam, and using the flat-top beam to move along the segment of the processing trajectory to process the target product; before the flat-top beam moves, marking the irradiation area formed by the flat-top beam on the target product as the second area, and determining the next traveling area of the flat-top beam according to the second area and the segment of the processing trajectory, denoted as the third area; when the flat-top beam moves, updating the second area and the third area in real time, and adjusting the intensity of the flat-top beam acting on the target product according to the temperature change of the second area and the third area. By doing so, for each segment of the processing trajectory, first use a Gaussian beam with strong focusing ability and concentrated energy for preheating. After the area where the Gaussian beam acts reaches the preset temperature, switch the Gaussian beam to a flat-top beam with sharp edges and uniform energy distribution. During the movement of the flat-top beam, adjust the intensity of the flat-top beam acting on the target product according to the temperature change to ensure that the temperature is consistent, so as to make the processing trace smooth, and solve the problem that the laser welding machine cannot self-adjust the intensity of the laser. Description of the Drawings

[0026] Figure 1 It is a flowchart of a method for adjusting the beam intensity for welding in an embodiment;

[0027] Figure 2 It is a structural block diagram of a device for adjusting the beam intensity for welding in an embodiment;

[0028] Figure 3 It is a structural block diagram of a laser welding machine in an embodiment;

[0029] Figure 4 It is an internal structural block diagram of the control module in an embodiment. Detailed Embodiments

[0030] In order to make the purpose, technical solutions and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0031] It will be appreciated that the terms "first", "second", etc. used in the present invention may be used herein to describe various elements, but unless otherwise specified, these elements are not limited by these terms. These terms are only used to distinguish one element from another. For example, without departing from the scope of the present invention, the first xx script may be referred to as the second xx script, and similarly, the second xx script may be referred to as the first xx script.

[0032] As Figure 1 shown, in one embodiment, a method for adjusting the beam light intensity for welding is proposed, which may specifically include the following steps:

[0033] S101, identify the processing surface of the target product and determine the processing trajectory on each processing surface;

[0034] S102, for each section of the processing trajectory, generate a Gaussian beam according to a preset light intensity, and use the Gaussian beam to preheat at the starting point of this section of the processing trajectory;

[0035] S103, mark the irradiation area formed by the Gaussian beam on the target product as the first area, and monitor the temperature of the first area;

[0036] S104, determine whether the temperature of the first area reaches a preset temperature. If so, switch the Gaussian beam to a flat-top beam, and use the flat-top beam to move along this section of the processing trajectory to process the target product;

[0037] S105, before the flat-top beam moves, mark the irradiation area formed by the flat-top beam on the target product as the second area, and determine the next traveling area of the flat-top beam according to the second area and this section of the processing trajectory, denoted as the third area;

[0038] S106, when the flat-top beam moves, update the second area and the third area in real time, and adjust the light intensity of the flat-top beam acting on the target product according to the temperature changes of the second area and the third area.

[0039] In this embodiment, processing the target product means welding the target product.

[0040] In this embodiment, the processing surface of the target product can be identified by an image acquisition module through image recognition; to determine the processing trajectory on each processing surface, after the image acquisition module recognizes the processing surface of the target product, the processing trajectory on the processing surface can be simulated on the control module according to the processing design file. The processing design file can be a file in the formats of stp, dxf, igs, etc.

[0041] In this embodiment, the starting point of the machining trajectory can be recognized by the image acquisition module, and the starting point of the machining trajectory can be moved to the laser working point through the moving module.

[0042] In this embodiment, both the Gaussian beam and the flat-top beam are lasers.

[0043] In this embodiment, the preset temperature can be set to the melting temperature of the material of the machining surface. If the temperature of the first region reaches the preset temperature, then S104 is repeated until the temperature of the first region reaches the preset temperature.

[0044] In this embodiment, moving the flat-top beam along this section of the machining trajectory to machine the target product can be to control the target product to move according to the machining trajectory through a moving device.

[0045] A method for adjusting the light intensity of a beam for welding provided by an embodiment of the present invention includes identifying the machining surface of a target product and determining the machining trajectory on each machining surface; for each section of the machining trajectory, generating a Gaussian beam according to a preset light intensity, and using the Gaussian beam to perform preheating at the starting point of this section of the machining trajectory; marking the irradiation area formed by the Gaussian beam on the target product as the first region, and monitoring the temperature of the first region; judging whether the temperature of the first region reaches the preset temperature, if so, switching the Gaussian beam to a flat-top beam, and moving the flat-top beam along this section of the machining trajectory to machine the target product; before the flat-top beam moves, marking the irradiation area formed by the flat-top beam on the target product as the second region, and determining the next traveling area of the flat-top beam according to the second region and this section of the machining trajectory, denoted as the third region; when the flat-top beam moves, updating the second region and the third region in real time, and adjusting the light intensity of the flat-top beam acting on the target product according to the temperature change conditions of the second region and the third region. By doing so, for each section of the machining trajectory, first use a Gaussian beam with strong focusing ability and concentrated energy for preheating. After the region where the Gaussian beam acts reaches the preset temperature, switch the Gaussian beam to a flat-top beam with sharp edges and uniform energy distribution. During the movement of the flat-top beam, adjust the light intensity of the flat-top beam acting on the target product according to the temperature change conditions to ensure that the temperature is consistent, so that the machining marks are smooth, and the problem that the laser welding machine cannot self-adjust the light intensity of the laser is solved.

[0046] In one embodiment, the generating a Gaussian beam according to a preset light intensity and using the Gaussian beam to perform preheating at the starting point of this section of the machining trajectory includes:

[0047] Obtaining the light intensity I1 corresponding to the melting of the material of the machining surface;

[0048] Obtaining the preset light intensity I2 from 2*I1;

[0049] From Obtain the total power of the Gaussian beam;

[0050] Control the laser emission module to generate a Gaussian beam according to the total power of the Gaussian beam;

[0051] Move the Gaussian beam to the starting point of this section of the processing trajectory and make the waist radius of the Gaussian beam equal to the radius of the irradiation area formed by the Gaussian beam on the target product, and then preheat the starting point of this section of the processing trajectory;

[0052] Where, ω is the waist radius of the Gaussian beam.

[0053] In this embodiment, the melting point of the material determines the lowest temperature that needs to be reached during beam processing, which has certain requirements for the light intensity of the beam. If the light intensity of the beam is too low, then the lowest temperature during beam processing cannot be reached, and the material cannot melt. Therefore, obtaining the light intensity I1 corresponding to the melting of the material on the processing surface is essentially obtaining the light intensity corresponding to the lowest temperature during beam processing.

[0054] In this embodiment, the light intensity I1 and the preset light intensity I2 refer to the peak light intensity.

[0055] In this embodiment, the preset light intensity is set to 2*I1 because at this time, there is no beam irradiation on this section of the processing trajectory and the temperature is relatively low. Using the preset light intensity can make the temperature rise rapidly. The reason for setting it to 2 times I1 is that when the waist radius of the Gaussian beam is equal to the radius of the area where the Gaussian beam acts on the target product, the energy acting on the processing surface is 86.5% of the total energy. Therefore, even if the total power of the Gaussian beam calculated by 2 times I1, the energy acting on the processing surface is 86.5% of the total energy, which is 73% more than the energy corresponding to the lowest temperature. In this way, the material will not be quickly burned due to excessive energy, and the material can be quickly heated.

[0056] In this embodiment, generally speaking, setting the transmission power of the laser emission module (i.e., the total power of the Gaussian beam), is determined by The peak light intensity of the laser (Gaussian beam) emitted by the laser emission module can be calculated. Light intensity is the energy passing through a unit area per unit time. The higher the light intensity, the greater the energy density of the laser and the stronger the effect on the material. After the material absorbs energy, it heats up and melts. The higher the energy, the faster the material heats up.

[0057] In this embodiment, the corresponding relationship between the light intensity and the peak light intensity at each point of the Gaussian beam is Where, I(d) represents the light intensity at a distance d from the central axis of the beam; I0 represents the peak light intensity at the center of the beam (d = 0), which is the maximum light intensity value of the beam; d represents the distance from the radial coordinate to the central axis of the beam; ω is the waist radius of the Gaussian beam, defined as the light intensity decays to 1 / e of I02 (13.5%). For a Gaussian beam, the region with the highest light intensity is the central region, and the light intensity within the waist radius of the Gaussian beam can be obtained from the corresponding relationship. The light intensity beyond the waist radius is too small, so the waist radius of the Gaussian beam is controlled to be equal to the radius of the area where the Gaussian beam acts on the target product, and then the starting point of this section of the processing trajectory is preheated.

[0058] In this embodiment, the laser emission module can directly generate a Gaussian beam.

[0059] In one embodiment, the monitoring of the temperature of the first region includes:

[0060] The temperature of the first region is identified by the temperature identification module to obtain the temperature contour map of the first region;

[0061] The temperature of each contour region in the first region is determined according to the temperature contour map of the first region;

[0062] The average value of the temperatures of each contour region in the first region is recorded as the temperature of the first region.

[0063] In this embodiment, the irradiation area formed by the Gaussian beam on the target product is a shape similar to a circle, so the first region can be regarded as a circle. The temperature contour map of the first region is a number of concentric circles. This is because the light intensity of the Gaussian beam smoothly decays from the center outwards, so different temperatures will appear in the first region. Due to the heat conduction effect of the material, the temperature will radiate to the nearby regions, that is, the temperatures of the nearby regions will interfere with each other, so the average value of the temperatures of each contour region in the first region is recorded as the temperature of the first region.

[0064] In one embodiment, the switching of the Gaussian beam to a flat-top beam includes:

[0065] Controlling the Gaussian beam to generate a flat-top beam through the beam shaping module;

[0066] Setting the n value of the beam shaping module so that the radius of the irradiation area formed by the flat-top beam on the target product is equal to the waist radius of the Gaussian beam.

[0067] In this embodiment, there are various types of beam shaping modules, such as diffractive optical elements (DOE), spatial light modulators (SLM), microlens arrays, refractive beam shapers, etc.

[0068] In this embodiment, the corresponding relationship between the light intensity and the peak light intensity at each point of the flat-top beam is Among them, n is the super-Gaussian order. When n equals 2, it is a Gaussian beam. Different from the Gaussian beam, R is the radius of the region with uniform light intensity, and this radius is related to n. Only when n equals 2, R is ω. For a flat-top beam, the larger n is, the flatter the light intensity in the central region and the steeper at the edges. For example, when n equals 8, the light intensity inside R of the flat-top beam is close to the peak light intensity, and the light intensity outside R is close to 0.

[0069] In this embodiment, the Gaussian beam is controlled to pass through the beam shaping module to generate a flat-top beam. At this time, the emission power of the laser emission module does not change, that is, the total power of the flat-top beam is equal to the total power of the Gaussian beam. Since the emission power of the laser emission module does not change, if the radius of the irradiation area formed by the flat-top beam on the target product is equal to the beam waist radius of the Gaussian beam, then the peak light intensity of the flat-top beam is only half of the peak light intensity of the Gaussian beam. When setting the preset light intensity I2, the light intensity I1 is multiplied by 2. Therefore, the peak light intensity of the flat-top beam is exactly equal to the light intensity I1 at this time. Of course, the radius of the irradiation area formed by the flat-top beam on the target product can also be greater than the beam waist radius of the Gaussian beam. In this case, the peak light intensity of the flat-top beam will be less than half of the peak light intensity of the Gaussian beam, that is, lower than the light intensity I1. Since the light intensity can be adjusted during the movement of the flat-top beam, such a processing method is also feasible. However, the present invention preferably selects the scheme where the radius of the irradiation area formed by the flat-top beam on the target product is equal to the beam waist radius of the Gaussian beam.

[0070] In this embodiment, according to the corresponding relationship between the light intensity at each point of the flat-top beam and the peak light intensity, it can be obtained that when n equals 8, the light intensity drops to 13.5% of the total power at the radius of the irradiation area formed by the flat-top beam on the target product, approaching the characteristics of the flat-top beam. Therefore, setting the n value of the beam shaping module is essentially that n is greater than or equal to 8.

[0071] In one embodiment, determining the next traveling area of the flat-top beam according to the second area and this section of the processing trajectory, denoted as the third area, includes:

[0072] Regularize the second area into a circle, denoted as the initial circle;

[0073] Determine the radius of the initial circle;

[0074] Determine a concentric circle with a radius of 3r and the center of the initial circle as the center;

[0075] Determine the ring where the initial circle and the concentric circle do not overlap, denoted as the area to be determined;

[0076] Determine a region with the same shape as the initial circle in the overlapping region of the area to be determined and this section of the processing trajectory, and determine this region as the next traveling area of the flat-top beam, denoted as the third area.

[0077] In this embodiment, the irradiation area formed by the flat-top beam on the target product is a shape similar to a circle, that is, the second area is a shape similar to a circle. Regularizing the second area into a circle can be achieved by algorithms such as the least squares method and the Hough transform.

[0078] In this embodiment, essentially the third area is the next second area.

[0079] In one embodiment, the real-time update of the second area and the third area includes:

[0080] Determine whether the irradiation area formed by the flat-top beam on the target product overlaps with the third area. If so, determine the third area as the new second area and delete the old second area to ensure that there is only one second area during the movement of the flat-top beam;

[0081] Determine the next traveling area of the flat-top beam according to the second area and this section of the processing trajectory, denoted as the new third area;

[0082] Delete the old third area to ensure that there is only one third area during the movement of the flat-top beam.

[0083] In this embodiment, when the flat-top beam moves, the flat-top beam has multiple working modes. For example, it moves a fixed distance and then emits the flat-top beam to act on the processing surface, and stays for a certain time at each stop so that the flat-top beam can complete the welding work at this position. The fixed distance of movement can be the diameter of the irradiation area formed by the flat-top beam on the target product. This way can reduce energy consumption while ensuring that all processing trajectories are processed as much as possible; another way is to always emit the flat-top beam during the movement. This way also requires staying for a certain time every time it moves a fixed distance so that the flat-top beam can complete the welding work at this position. The fixed distance of movement can be the diameter of the irradiation area formed by the flat-top beam on the target product. The process is basically the same as the previous one, except that there is some additional energy consumption during the movement. Based on these two working modes, it can be obtained that the fixed distance is essentially the distance from the center point of the second area to the center point of the third area. Therefore, the third area is the new second area. The second area is the irradiation area formed by the flat-top beam on the target product, which is a real-time irradiation area. There can only be one second area at the same time, and the third area is calculated based on the second area. Whenever the second area changes, the third area also changes accordingly.

[0084] In one embodiment, the adjustment of the light intensity of the flat-top beam acting on the target product according to the temperature change conditions of the second area and the third area includes:

[0085] The temperature of the second area is identified through the temperature identification module to obtain the temperature contour map of the second area;

[0086] The temperatures of the second area and the third area are monitored respectively;

[0087] The temperature change rate k of the second area is obtained from (T2 - T1) / t;

[0088] The light intensity I3 of the flat-top beam is determined by P / A;

[0089] A corresponding relationship between the light intensity I3 and the temperature change rate k is established;

[0090] The to-be-changed rate K of the third area is obtained from (T2 - T3) / t;

[0091] The to-be-changed light intensity I4 is obtained by substituting the to-be-changed rate K into the coordinate system of the corresponding relationship between the light intensity I3 and the temperature change rate k;

[0092] The to-be-adjusted power is obtained from (I4 - I3)*A;

[0093] According to the to-be-adjusted power, the real-time total power for generating the flat-top beam is adjusted, and thus the light intensity of the flat-top beam acting on the target product is adjusted;

[0094] Wherein, t is the residence time of the flat-top beam in the second area, T2 is the cut-off temperature of the second area at the end of the residence time, T1 is the starting temperature of the second area at the start of the residence time, P is the real-time total power for generating the flat-top beam, A is the irradiation area formed by the flat-top beam on the target product, and T3 is the cut-off temperature of the third area at the end of the residence time.

[0095] In this embodiment, the steps of monitoring the temperatures of the second area and the third area respectively are the same as the steps of monitoring the temperature of the first area.

[0096] In this embodiment, the corresponding relationship formula between the light intensity at each point of the flat-top beam and the peak light intensity is The integral light intensity can be obtained to get Ideally, P = πR 2 I 0 , and the radius of the irradiation area formed by the flat-top beam on the target product is equal to the beam waist radius of the Gaussian beam. Therefore, A = πR 2 = πω 2 . In the ideal case of the flat-top beam, the light intensity within R of the flat-top beam can be regarded as the peak light intensity. Therefore, the light intensity I3 of the flat-top beam is determined by P / A.

[0097] In this embodiment, adjusting the real-time total power for generating the flat-top beam according to the to-be-adjusted power means adding or subtracting the to-be-adjusted power to / from the original total power of the flat-top beam to obtain the new total power.

[0098] In this embodiment, I4 - I3 can be either positive or negative. Therefore, the power to be adjusted can be either positive or negative. If it is positive, it means adding the power to be adjusted to the original total power of the flat - top beam. If it is negative, it means subtracting the power to be adjusted from the original total power of the flat - top beam.

[0099] In this embodiment, since P = πR 2 I 0 , so the essence of adjusting the light intensity is to adjust the emission power of the laser emission module. And the flat - top beam is transformed from a Gaussian beam, and the laser emission module emits a Gaussian beam. So essentially, the total power of the Gaussian beam is adjusted.

[0100] In this embodiment, the residence time of the flat - top beam in the second region can be obtained based on the residence time of the flat - top beam in the first second region. For example, the image recognition module can identify the processing marks when the flat - top beam is used for welding in the first second region. For example, identify the depth of the processing marks during the melting process. When the depth of the processing marks reaches the required depth for processing, move the flat - top beam and calculate the processing time of the flat - top beam for the first second region. This time is the residence time of the flat - top beam in the second region. In addition to the image recognition module, the residence time can also be calculated by monitoring the pressure and flow rate of the auxiliary gas through the gas monitoring module.

[0101] In this embodiment, since the third region is not directly irradiated by the flat - top beam, the temperature of the third region is lower than that of the second region. Therefore, for the third region, heating is required, but only the heating amplitude will change.

[0102] In this embodiment, T3 is not necessarily equal to T1 because the flat - top beam moves onto the third region. During the movement, if the flat - top beam keeps emitting all the time, then T3 may be greater than T1 but less than T2; if the flat - top beam only emits in the second region, then due to heat dissipation and thermal effects, T3 may be less than T1.

[0103] In one embodiment, establishing the correspondence between the light intensity I3 and the temperature change rate k includes:

[0104] Establish a coordinate system with the light intensity as the horizontal axis and the change rate as the vertical axis;

[0105] One - to - one correspond the light intensity I3 and the temperature change rate k to form several data groups;

[0106] Mark all the data groups on the coordinate system one by one;

[0107] Determine whether the number of data groups is 1. If so, use the linear regression equation to calculate the corresponding relationship between the light intensity I3 and the temperature change rate k based on the origin of the coordinate system and this data group. If not, use the linear regression equation to calculate the corresponding relationship between the light intensity I3 and the temperature change rate k based on all data groups.

[0108] In this embodiment, when the number of data groups is 1, only the origin of the coordinate system can be used as the data group. As the number of data groups increases, the corresponding relationship between the strong I3 and the temperature change rate k will be more accurate.

[0109] In this embodiment, the corresponding relationship between the light intensity I3 and the temperature change rate k is updated every time a data group is generated.

[0110] As Figure 2 shown, in one embodiment, a beam light intensity adjustment device for welding is provided, which may specifically include:

[0111] A trajectory determination module, configured to identify the processing surface of the target product and determine the processing trajectory on each processing surface;

[0112] A first processing module, configured to, for each segment of the processing trajectory, generate a Gaussian beam according to a preset light intensity, and use the Gaussian beam to perform preheating at the starting point of this segment of the processing trajectory;

[0113] A temperature detection module, configured to mark the irradiation area formed by the Gaussian beam on the target product as the first area and monitor the temperature of the first area;

[0114] A beam switching module, configured to determine whether the temperature of the first area reaches a preset temperature. If so, switch the Gaussian beam to a flat-top beam, and use the flat-top beam to move along this segment of the processing trajectory to process the target product;

[0115] An area identification module, configured to, before the flat-top beam moves, mark the irradiation area formed by the flat-top beam on the target product as the second area, and determine the next traveling area of the flat-top beam according to the second area and this segment of the processing trajectory, denoted as the third area;

[0116] A light intensity adjustment module, configured to, when the flat-top beam moves, update the second area and the third area in real time, and adjust the light intensity of the flat-top beam acting on the target product according to the temperature change conditions of the second area and the third area.

[0117] In this embodiment, each module of the beam light intensity adjustment device for welding is modularized in the method part of the present invention. For the specific explanations of each module, please refer to the corresponding content in the method part of the present invention. The embodiments of the present invention will not be elaborated herein.

[0118] AsFigure 3 As shown, in one embodiment, a laser welding machine is provided, which may specifically include: a laser emission module, a temperature recognition module, a beam shaping module, and a control module;

[0119] The laser emission module is connected to the control module and is used to generate a Gaussian beam;

[0120] The temperature recognition module is connected to the control module and is used to recognize temperature;

[0121] The beam shaping module is connected to the control module and is used to transform the Gaussian beam into a flat-top beam;

[0122] The control module is used to execute the steps of the above-mentioned beam intensity adjustment method for welding.

[0123] In this embodiment, conventional modules such as a moving module, an image recognition module, and a gas monitoring module are further included. The moving module can be used to move the target product or can be used to move the Gaussian beam or the flat-top beam. The temperature recognition module can be an image recognition module with temperature detection, so the image recognition module can be combined with the temperature recognition module. The gas monitoring module is used to monitor the pressure and flow rate of the auxiliary gas. The auxiliary gas can effectively isolate air and prevent the metal in the welding area from oxidizing, thereby ensuring the welding quality. The auxiliary gas can be nitrogen, argon, etc.

[0124] A laser welding machine provided by an embodiment of the present invention identifies a processing surface of a target product and determines a processing trajectory on each processing surface; for each segment of the processing trajectory, a Gaussian beam is generated according to a preset light intensity, and the Gaussian beam is used for preheating at the starting point of the segment of the processing trajectory; the irradiation area formed by the Gaussian beam on the target product is marked as the first area, and the temperature of the first area is monitored; it is judged whether the temperature of the first area reaches a preset temperature, and if so, the Gaussian beam is switched to a flat-top beam, and the flat-top beam is used to move along the segment of the processing trajectory to process the target product; before the flat-top beam moves, the irradiation area formed by the flat-top beam on the target product is marked as the second area, and a next traveling area of the flat-top beam is determined according to the second area and the segment of the processing trajectory, denoted as the third area; when the flat-top beam moves, the second area and the third area are updated in real time, and the light intensity of the flat-top beam acting on the target product is adjusted according to the temperature change conditions of the second area and the third area. By doing so, for each segment of the processing trajectory, first, a Gaussian beam with strong focusing ability and concentrated energy is used for preheating. After the area where the Gaussian beam acts reaches the preset temperature, the Gaussian beam is switched to a flat-top beam with sharp edges and uniform energy distribution. During the movement of the flat-top beam, the light intensity of the flat-top beam acting on the target product is adjusted according to the temperature change conditions to ensure that the temperature is consistent, so that the processing trace is smooth, and the problem that the laser welding machine cannot self-adjust the light intensity of the laser is solved.

[0125] Figure 4 The internal structure diagram of the control module in one embodiment is shown. As Figure 4 shown, the control module includes a processor, a memory, a network interface, an input device, and a display screen connected through a system bus. Among them, the memory includes a non-volatile storage medium and an internal memory. The non-volatile storage medium of the control module stores an operating system and can also store a computer program. When the computer program is executed by the processor, the processor can implement a method for adjusting the light intensity of a beam for welding provided by an embodiment of the present invention. The internal memory can also store a computer program. When the computer program is executed by the processor, the processor can execute a method for adjusting the light intensity of a beam for welding provided by an embodiment of the present invention. The display screen of the control module can be a liquid crystal display screen or an electronic ink display screen. The input device of the control module can be a touch layer covered on the display screen, or a button, a trackball, or a touchpad provided on the outer shell of the control module, or an external keyboard, touchpad, or mouse, etc.

[0126] Those skilled in the art can understand, Figure 4The structure shown is only a block diagram of some structures related to the solution of the present invention, and does not constitute a limitation on the control module to which the solution of the present invention is applied. The specific control module may include more or fewer components than those shown in the figure, or combine some components, or have a different component arrangement.

[0127] In one embodiment, a beam light intensity adjustment device for welding provided by an embodiment of the present invention can be implemented in the form of a computer program, and the computer program can run on a control module as shown in Figure 4 The memory of the control module can store each program module that constitutes a beam light intensity adjustment device for welding. For example, Figure 2 the determined trajectory module, the first processing module, the temperature detection module, the beam switching module, the area recognition module, and the light intensity adjustment module shown in. The computer program composed of each program module enables the processor to execute the steps in a beam light intensity adjustment method for welding according to various embodiments of the present invention described in this specification.

[0128] For example, Figure 4 the control module shown in can execute step S101 through the determined trajectory module in a beam light intensity adjustment device for welding as shown in Figure 2 The control module can execute step S102 through the first processing module; the control module can execute step S103 through the temperature detection module; the control module can execute step S104 through the beam switching module; the control module can execute step S105 through the area recognition module; the control module can execute step S106 through the light intensity adjustment module.

[0129] In one embodiment, a control module is proposed. The control module includes a memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the computer program, the following steps are implemented:

[0130] S101, identify the processing surface of the target product and determine the processing trajectory on each processing surface;

[0131] S102, for each segment of the processing trajectory, generate a Gaussian beam according to a preset light intensity, and use the Gaussian beam to perform preheating at the starting point of this segment of the processing trajectory;

[0132] S103, mark the irradiation area formed by the Gaussian beam on the target product as the first area, and monitor the temperature of the first area;

[0133] S104, determine whether the temperature of the first area reaches a preset temperature. If so, switch the Gaussian beam to a flat-top beam, and use the flat-top beam to move along this segment of the processing trajectory to process the target product;

[0134] S105. Before the flat-top beam moves, mark the irradiation area formed by the flat-top beam on the target product as the second area, and determine the next traveling area of the flat-top beam according to the second area and this section of the processing trajectory, denoted as the third area;

[0135] S106. When the flat-top beam moves, update the second area and the third area in real time, and adjust the light intensity of the flat-top beam acting on the target product according to the temperature changes of the second area and the third area.

[0136] In one embodiment, a computer-readable storage medium is provided. A computer program is stored on the computer-readable storage medium. When the computer program is executed by a processor, the processor performs the following steps:

[0137] S101. Identify the processing surface of the target product and determine the processing trajectory on each processing surface;

[0138] S102. For each section of the processing trajectory, generate a Gaussian beam according to a preset light intensity, and use the Gaussian beam to preheat at the starting point of this section of the processing trajectory;

[0139] S103. Mark the irradiation area formed by the Gaussian beam on the target product as the first area, and monitor the temperature of the first area;

[0140] S104. Determine whether the temperature of the first area reaches a preset temperature. If so, switch the Gaussian beam to a flat-top beam, and use the flat-top beam to move along this section of the processing trajectory to process the target product;

[0141] S105. Before the flat-top beam moves, mark the irradiation area formed by the flat-top beam on the target product as the second area, and determine the next traveling area of the flat-top beam according to the second area and this section of the processing trajectory, denoted as the third area;

[0142] S106. When the flat-top beam moves, update the second area and the third area in real time, and adjust the light intensity of the flat-top beam acting on the target product according to the temperature changes of the second area and the third area.

[0143] It should be understood that although the steps in the flowcharts of the embodiments of the present invention are shown sequentially as indicated by the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless there is a clear indication in this article, the execution of these steps has no strict order restriction, and these steps can be executed in other orders. Moreover, at least a part of the steps in each embodiment may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily executed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed alternately or in turn with at least a part of other steps or sub-steps or stages of other steps.

[0144] Those of ordinary skill in the art can understand that all or part of the processes of implementing the methods in the above embodiments can be completed by instructing relevant hardware through a computer program. The program can be stored in a non-volatile computer-readable storage medium. When the program is executed, it can include the processes of the embodiments of the above methods. Among them, any reference to a memory, storage, database or other medium used in the embodiments provided by the present invention can include non-volatile and / or volatile memories. Non-volatile memories can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memories can include random access memory (RAM) or external cache memory. By way of illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM), etc.

[0145] The technical features of the above-described embodiments can be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope described in this specification.

[0146] The above-described embodiments merely represent several implementation manners of the present invention. The description is relatively specific and detailed, but it should not be construed as a limitation on the scope of the patent of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all belong to the protection scope of the present invention.

Claims

1. A method for adjusting the intensity of a welding beam, characterized in that: The welding beam light intensity adjustment method comprises: S101, identifying the processing surface of the target product and determining the processing trajectory on each processing surface; S102, for each processing track, generating a Gaussian beam according to a preset light intensity, and using the Gaussian beam to perform preheating at the starting point of the processing track; S103, marking the irradiation area formed by the Gaussian beam on the target product as a first area, and monitoring the temperature of the first area; S104, determining whether the temperature of the first area reaches a preset temperature, and if so, switching the Gaussian beam to a flat-top beam, and using the flat-top beam to move along the processing trajectory to process the target product; S105, before the flat-top beam moves, marking the irradiation area formed by the flat-top beam on the target product as the second area, and determining the next travel area of ​​the flat-top beam according to the second area and the processing trajectory, which is recorded as the third area; S106, when the flat-top light beam moves, the second area and the third area are updated in real time, and the light intensity of the flat-top light beam acting on the target product is adjusted according to the temperature change of the second area and the third area.

2. The method for adjusting the intensity of a welding beam according to claim 1, characterized in that: The method of generating a Gaussian beam according to a preset light intensity and using the Gaussian beam to perform preheating at the starting point of the processing track section includes: Obtain the light intensity I1 corresponding to the melting of the material on the processing surface; The preset light intensity I2 is obtained by 2*I1; Depend on Get the total power of the Gaussian beam; Controlling the laser emission module to generate a Gaussian beam according to the total power of the Gaussian beam; The Gaussian beam is moved to the starting point of the processing track section and the waist radius of the Gaussian beam is made equal to the radius of the irradiation area formed by the Gaussian beam on the target product, thereby preheating the starting point of the processing track section; Here, ω is the waist radius of the Gaussian beam.

3. The method for adjusting the intensity of a welding beam according to claim 1, characterized in that: The monitoring of the temperature of the first area comprises: Performing temperature recognition on the first area by using a temperature recognition module to obtain a temperature contour map of the first area; Determining the temperature of each contour area of ​​the first area according to the temperature contour map of the first area; The average value of the temperatures of each equal-height region in the first region is recorded as the temperature of the first region.

4. The method for adjusting the intensity of a welding beam according to claim 1, characterized in that: The step of switching the Gaussian beam to a flat-top beam comprises: Controlling the Gaussian beam to generate a flat-top beam through a beam shaping module; The n value of the beam shaping module is set so that the radius of the irradiation area formed by the flat-top beam on the target product is equal to the waist radius of the Gaussian beam.

5. The method for adjusting the intensity of a welding beam according to claim 1, characterized in that: The next traveling area of ​​the flat-top beam is determined according to the second area and the processing track, which is recorded as the third area, and includes: The second area is regularized into a circle, which is recorded as the initial circle; Determine the radius of the initial circle; Determine a concentric circle with 3r as radius and the center of the initial circle as the center; According to the initial circle and the concentric circles, the circular rings that do not overlap between the two are determined and recorded as the area to be determined; An area with the same initial circular shape is determined in the area where the to-be-determined area overlaps with the processing track section, and the area is determined as the next traveling area of ​​the flat-top beam, which is recorded as the third area.

6. The method for adjusting the intensity of a welding beam according to claim 1, characterized in that: The real-time updating of the second area and the third area includes: Determine whether the irradiation area formed by the flat-top beam on the target product overlaps with the third area. If so, determine the third area as a new second area and delete the old second area to ensure that there is only one second area during the movement of the flat-top beam. Determine the next travel area of ​​the flat-top beam according to the second area and the processing track, and record it as a new third area; The old third region is deleted to keep only one third region during the movement of the flat-top beam.

7. The method for adjusting the intensity of a welding beam according to claim 1, characterized in that: The step of adjusting the light intensity of the flat-top light beam acting on the target product according to the temperature changes of the second area and the third area includes: Performing temperature recognition on the second area by using a temperature recognition module to obtain a temperature contour map of the second area; respectively monitoring the temperatures of the second area and the third area; The temperature change rate k of the second region is obtained by (T2-T1) / t; The intensity I3 of the flat-top beam is determined by P / A; Establish the corresponding relationship between light intensity I3 and temperature change rate k; The waiting rate K of the third region is obtained by (T2-T3) / t; Substitute the change rate K into the corresponding coordinate system of the light intensity I3 and the temperature change rate k to obtain the light intensity I4 to be changed; The power to be adjusted is obtained by (I4-I3)*A; The real-time total power of the generated flat-top beam is adjusted according to the power to be adjusted, thereby adjusting the light intensity of the flat-top beam acting on the target product; Wherein, t is the residence time of the flat-top beam in the second area, T2 is the cutoff temperature of the second area at the end of the residence time, T1 is the starting temperature of the second area at the start of the residence time, P is the real-time total power of the generated flat-top beam, A is the irradiation area formed by the flat-top beam on the target product, and T3 is the cutoff temperature of the third area at the end of the residence time.

8. The method for adjusting the intensity of a welding beam according to claim 7, characterized in that: The establishing of the corresponding relationship between the light intensity I3 and the temperature change rate k includes: Establish a coordinate system with light intensity as the horizontal axis and rate of change as the vertical axis; The light intensity I3 and the temperature change rate k are matched one by one to form several data groups; Mark all data sets one by one on the coordinate system; Determine whether the number of data groups is 1. If so, use the linear regression equation to calculate the correspondence between the light intensity I3 and the temperature change rate k based on the origin of the coordinate system and the data group. If not, use the linear regression equation to calculate the correspondence between the light intensity I3 and the temperature change rate k based on all data groups.

9. A beam intensity adjustment device for welding, characterized in that: The welding light beam intensity adjustment device comprises: A trajectory determination module is used to identify the processing surface of the target product and determine the processing trajectory on each processing surface; A first processing module is used to generate a Gaussian beam according to a preset light intensity for each processing track, and use the Gaussian beam to perform preheating at the starting point of the processing track; A temperature detection module, used for marking an irradiation area formed by the Gaussian beam on the target product as a first area, and monitoring the temperature of the first area; A beam switching module is used to determine whether the temperature of the first area reaches a preset temperature. If so, the Gaussian beam is switched to a flat-top beam, and the flat-top beam is used to move along the processing track to process the target product. The area recognition module is used to mark the irradiation area formed by the flat-top beam on the target product as the second area before the flat-top beam moves, and determine the next travel area of ​​the flat-top beam according to the second area and the processing trajectory, which is recorded as the third area; The light intensity adjustment module is used to update the second area and the third area in real time when the flat-top light beam moves, and adjust the light intensity of the flat-top light beam acting on the target product according to the temperature change of the second area and the third area.

10. A laser welding machine, characterized in that: The laser welding machine comprises: a laser emission module, a temperature recognition module, a beam shaping module, and a control module; The laser emission module is connected to the control module and is used to generate a Gaussian beam; The temperature identification module is connected to the control module and is used to identify the temperature; The beam shaping module is connected to the control module and is used to transform the Gaussian beam into a flat-top beam; The control module is used to execute the steps of the welding beam intensity adjustment method according to any one of claims 1 to 8.

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