A method and device for adjusting the intensity of a light beam for welding, and a laser welding machine

Abstract

The present application relates to the technical field of laser welding, in particular to a kind of welding beam light intensity adjusting method, device and laser welding machine.The method comprises: identifying the processing surface of target product and its processing track;For each processing track, generate Gaussian beam and preheat at the starting point of the processing track;Determine the first region and monitor its temperature;Judge whether the temperature of the first region reaches the preset temperature, if yes, switch Gaussian beam to flat-top beam and move along the processing track to process the target product;Before flat-top beam moves, determine the second region and third region;When flat-top beam moves, the second region and third region are updated in real time, and the light intensity of flat-top beam acting on the target product is adjusted according to the temperature change of the second region and third region.The present application solves the problem that laser welding machine cannot self-adjust the light intensity of laser.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of laser welding, in particular to a light intensity adjustment method and device for welding and a laser welding machine. BACKGROUND

[0002] The laser welding machine is a device that uses a high-energy density laser beam as a heat source for welding. It melts the material and forms a weld by the interaction of the laser beam and the material.

[0003] Currently, the light intensity of the laser of the laser welding machine is generally determined by first manually adjusting the light intensity of the laser that can melt the processing material, and then using the laser beam corresponding to the light intensity to melt the processing material to complete the welding work.

[0004] In this way, the light intensity of the laser is fixed throughout the welding process, while for the processing material, there is a protective layer or oxide film on the surface, and the melting temperature of the surface and the interior of the processing material is inconsistent. In the working process, since the laser always acts on the surface of the processing material, the temperature of the area near the laser rises in advance due to the influence of the laser, and the temperature of the points on the laser motion track is inconsistent. If a laser with fixed light intensity is used, the processing trace will be rough due to the inconsistent temperature, so it is unreasonable to use a laser with 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

[0005] Therefore, it is necessary to provide a light intensity adjustment method and device for welding and a laser welding machine to solve the above problems.

[0006] The embodiment of the present application is implemented as follows: a light intensity adjustment method for welding, the light intensity adjustment method for welding comprises:

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

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

[0009] 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;

[0010] S104, judging whether the temperature of the first area reaches a preset temperature, if yes, switching the Gaussian beam to a flat-top beam, and using the flat-top beam to move along the processing track to process the target product;

[0011] S105, before the flat-top beam moves, marking an irradiation area formed by the flat-top beam on the target product as a second area, determining a next travel area of the flat-top beam according to the second area and the segment of the machining track, and marking the next travel area as a third area;

[0012] S106, updating the second area and the third area in real time while the flat-top beam moves, and adjusting 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.

[0013] In one of the embodiments, the present application provides a light intensity adjusting device for a welding light beam, which comprises:

[0014] a track determining module, configured to identify a machining surface of a target product and determine a machining track on each machining surface;

[0015] a first machining module, configured to, for each segment of the machining track, generate a Gaussian light beam according to a preset light intensity, and preheat at a starting point of the segment of the machining track by using the Gaussian light beam;

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

[0017] a light beam switching module, configured to determine whether the temperature of the first area reaches a preset temperature, and if so, switch the Gaussian light beam to a flat-top beam, and move the flat-top beam along the segment of the machining track to machine the target product;

[0018] a region identifying module, configured to, before the flat-top beam moves, mark an irradiation area formed by the flat-top beam on the target product as a second area, and determine a next travel area of the flat-top beam according to the second area and the segment of the machining track, and mark the next travel area as a third area;

[0019] a light intensity adjusting module, configured to update the second area and the third area in real time while the flat-top beam moves, 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.

[0020] In one of the embodiments, the present application provides a laser welding machine, which comprises a laser emission module, a temperature identifying module, a light 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 light beam;

[0022] the temperature identifying module is connected to the control module, and is configured to identify a temperature;

[0023] The light beam shaping module is connected with the control module, and is used for transforming the Gaussian light beam into a flat-top light beam.

[0024] The control module is used for executing the steps of the light intensity adjustment method for the light beam used for welding.

[0025] The light intensity adjustment method for the light beam used for welding provided by the embodiment of the present application identifies the machining surface of the target product and determines the machining track on each machining surface; for each machining track, a Gaussian light beam is generated according to a preset light intensity, and the Gaussian light beam is used for preheating at the starting point of the machining track; an irradiation area formed by the Gaussian light beam on the target product is marked as a 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, if yes, the Gaussian light beam is switched into a flat-top light beam, and the flat-top light beam is used for moving along the machining track to process the target product; before the flat-top light beam moves, an irradiation area formed by the flat-top light beam on the target product is marked as a second area, a next travel area of the flat-top light beam is determined according to the second area and the machining track, and is recorded as a third area; 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. In this way, for each machining track, the Gaussian light beam with strong focusing ability and concentrated energy is used for preheating first, the Gaussian light beam is switched into the flat-top light beam with sharp edge and uniform energy distribution after the area affected by the Gaussian light beam reaches the preset temperature, and the light intensity of the flat-top light beam acting on the target product is adjusted according to the temperature change in the process of moving of the flat-top light beam to ensure that the temperature is consistent and the machining trace is smooth, thereby solving the problem that the laser welding machine cannot self-adjust the light intensity of the laser. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 A flow chart of a light intensity adjustment method for a light beam used for welding in an embodiment;

[0027] Figure 2 A structure block diagram of a light intensity adjustment device for a light beam used for welding in an embodiment;

[0028] Figure 3 A structure block diagram of a laser welding machine in an embodiment;

[0029] Figure 4 An internal structure block diagram of a control module in an embodiment. DETAILED DESCRIPTION

[0030] In order to make the purpose, technical scheme and advantages of the present application more clear, the present application is 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 application, and are not used to limit the present application.

[0031] It is to be understood that the terms "first", "second", and the like used herein can be used to describe various elements, but unless specifically stated otherwise, these elements are not limited by these terms. These terms are only used to distinguish one element from another. For example, a first xx script can be referred to as a second xx script, and similarly, a second xx script can be referred to as a first xx script, without departing from the scope of the present application.

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

[0033] S101, identifying the machining surface of the target product and determining the machining track on each machining surface;

[0034] S102, for each machining track, generating a Gaussian light beam according to a preset light intensity, and using the Gaussian light beam to preheat at the starting point of the machining track;

[0035] S103, marking the irradiation area formed by the Gaussian light beam on the target product as a first area, and monitoring the temperature of the first area;

[0036] S104, judging whether the temperature of the first area reaches a preset temperature, if yes, switching the Gaussian light beam to a flat-top light beam, and using the flat-top light beam to move along the machining track to process the target product;

[0037] S105, before the flat-top light beam moves, marking the irradiation area formed by the flat-top light beam on the target product as a second area, and determining the next travel area of the flat-top light beam according to the second area and the machining track, which is recorded as a third area;

[0038] S106, updating the second area and the third area in real time when the flat-top light beam moves, and 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.

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

[0040] In this embodiment, identifying the machining surface of the target product can be obtained by image recognition through the image acquisition module; and determining the machining track on each machining surface can be simulated on the control module according to the machining design file after the image acquisition module identifies the machining surface of the target product. The machining design file can be a file in stp, dxf, igs, etc.

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

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

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

[0044] In the embodiment, the flat-top beam is used to move along the segment of the machining track to process the target product, which can be that the target product is controlled to move according to the machining track by the moving device.

[0045] The method for adjusting the light intensity of the light beam for welding provided by the embodiment of the application comprises the following steps: recognizing the machining surface of a target product and determining the machining track on each machining surface; for each segment of the machining track, generating a Gaussian beam according to a preset light intensity, and preheating at the starting point of the segment of the machining track by using the Gaussian beam; marking the irradiation region formed on the target product by the Gaussian beam as a first region, and monitoring the temperature of the first region; determining whether the temperature of the first region reaches a preset temperature, and if so, switching the Gaussian beam to a flat-top beam, and moving the flat-top beam along the segment of the machining track to process the target product; before the flat-top beam moves, marking the irradiation region formed on the target product by the flat-top beam as a second region, determining the next travel region of the flat-top beam according to the second region and the segment of the machining track, and marking the next travel region as a 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 of the second region and the third region. In this way, for each segment of the machining track, the Gaussian beam with strong focusing ability and concentrated energy is used for preheating first, the Gaussian beam is switched to the flat-top beam with sharp edges and uniform energy distribution after the region affected by the Gaussian beam reaches the preset temperature, the light intensity of the flat-top beam acting on the target product is adjusted according to the temperature change in the process of moving the flat-top beam to ensure that the temperature is consistent, so that the machining trace is 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 step of generating the Gaussian beam according to the preset light intensity and preheating at the starting point of the segment of the machining track by using the Gaussian beam comprises the following steps:

[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] Obtaining the preset light intensity I2 from I1+I1; obtaining the total power of the Gaussian beam;

[0050] controlling the laser emitting module to generate the Gaussian beam according to the total power of the Gaussian beam;

[0051] moving the Gaussian beam to the starting point of the segment of the machining track and making 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 preheating the starting point of the segment of the machining track;

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

[0053] In the embodiment, the melting point of the material determines the minimum temperature required to be reached during the beam machining, which has certain requirements for the light intensity of the beam. If the light intensity of the beam is too low, the minimum temperature required during the beam machining cannot be reached, and therefore the material cannot be melted. Therefore, the light intensity I1 corresponding to the melting of the material on the machining surface is essentially the light intensity corresponding to the minimum temperature required during the beam machining.

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

[0055] In the embodiment, the preset light intensity is set as 2*I1, because at this time the segment of the machining track has not been irradiated by the beam, and the temperature is relatively low. The preset light intensity can make the temperature rise rapidly. The reason why it is set as 2*I1 is that when the waist radius of the Gaussian beam is equal to the radius of the area on which the Gaussian beam acts on the target product, the energy acting on the machining surface is 86.5% of the total energy. Therefore, even if the total power of the Gaussian beam calculated based on 2*I1, the energy acting on the machining surface is 86.5% of the total energy, which is 73% more than the energy corresponding to the light intensity of the minimum temperature. In this way, the material will not be quickly burned due to excessive energy, and the material can also be quickly heated.

[0056] In the embodiment, generally, the transmission power of the laser emitting module (i.e. the total power of the Gaussian beam) is set as The peak light intensity of the laser (Gaussian beam) generated by the laser emitting module can be calculated, and the light intensity is the energy of light 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 is heated and melted. The higher the energy, the faster the material is heated.

[0057] In the embodiment, the corresponding relationship between the light intensity of the Gaussian beam at each position and the peak light intensity is wherein I(d) represents the light intensity at a distance d from the center axis of the beam; I0 represents the peak light intensity of the center of the beam (d=0), which is the maximum light intensity value of the beam; d represents the distance of the radial coordinate to the center axis of the beam; and ω is the waist radius of the Gaussian beam, which is defined as the distance at which the light intensity decays to 1 / e of I0.2 For a Gaussian beam, the region with the highest light intensity is the central region, and the light intensity within the beam waist radius of the Gaussian beam can be obtained by the corresponding relationship. The light intensity beyond the beam waist radius is too small, so the beam waist radius of the controlled Gaussian beam is equal to the radius of the area on which the Gaussian beam acts on the target product, and the starting point of the processing track is preheated.

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

[0059] In one embodiment, the temperature of the first region is monitored, including:

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

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

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

[0063] In this embodiment, the irradiation region 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 plurality of concentric circles, because the light intensity of the Gaussian beam smoothly decays from the center to the outside, so different temperatures will appear in the first region. Due to the heat conduction effect of the material, the temperature will be radiated to the nearby region, that is, the temperatures of the nearby regions will interfere with each other, so the average value of the temperature of each contour region of the first region is recorded as the temperature of the first region.

[0064] In one embodiment, the Gaussian beam is switched to a flat-top beam, including:

[0065] The Gaussian beam is controlled to pass through the beam shaping module to generate a flat-top beam;

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

[0067] In this embodiment, the beam shaping module has a variety of types, such as a diffractive optical element (DOE), a spatial light modulator (SLM), a microlens array, a refractive beam shaper, etc.

[0068] In this embodiment, the corresponding relationship between the light intensity of the flat-top beam at each location and the peak light intensity is Wherein, 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 uniform light intensity area, which is related to n. Only when n equals 2, R is ω. For the flat-top beam, the larger n is, the more flat the light intensity in the central region is, and the steeper the edge is. For example, when n equals 8, the light intensity of the flat-top beam in R is close to the peak light intensity, and the light intensity outside R is close to 0.

[0069] In the embodiment, the Gaussian beam is controlled to generate the flat-top beam through the beam shaping module, and the emission power of the laser emission module does not change, i.e., 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 waist radius of the Gaussian beam, the peak light intensity of the flat-top beam is only half of the peak light intensity of the Gaussian beam. When the preset light intensity I2 is set, the light intensity I1 is multiplied by 2, so the peak light intensity of the flat-top beam is exactly equal to the light intensity I1. Of course, the radius of the irradiation area formed by the flat-top beam on the target product can also be greater than the waist radius of the Gaussian beam, so that the peak light intensity of the flat-top beam is less than half of the peak light intensity of the Gaussian beam, i.e., lower than the light intensity I1. Since the light intensity can be adjusted during the movement of the flat-top beam, such a processing mode is also feasible, but the application preferentially selects the scheme in which 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.

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

[0071] In one embodiment, the next moving area of the flat-top beam is determined according to the second area and the segment of the machining track, and is recorded as a third area.

[0072] The second area is regularized into a circle, which is recorded as an initial circle;

[0073] The radius of the initial circle is determined;

[0074] A concentric circle is determined with 3r as the radius and the center of the initial circle as the center;

[0075] The annulus in which the initial circle and the concentric circle do not coincide is determined according to the initial circle and the concentric circle, and is recorded as a to-be-determined area;

[0076] An area with the same shape as the initial circle is determined in the area in which the to-be-determined area and the segment of the machining track overlap, and the area is determined as the next moving area of the flat-top beam, and is recorded as a third area.

[0077] In the embodiment, the irradiation area formed by the flattop beam on the target product is a shape similar to a circle, i.e., the second area is a shape similar to a circle. The second area can be regularized as a circle by using algorithms such as least square method and Hough transform.

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

[0079] In an embodiment, the real-time updating of the second area and the third area comprises:

[0080] determining whether the irradiation area formed by the flattop beam on the target product overlaps with the third area, and if so, determining the third area as a new second area and deleting the old second area to keep only one second area during the movement of the flattop beam;

[0081] determining a next travel area of the flattop beam according to the second area and the segment of the processing track, and recording the next travel area as a new third area;

[0082] deleting the old third area to keep only one third area during the movement of the flattop beam.

[0083] In the embodiment, the flattop beam has multiple working modes during the movement of the flattop beam, such as moving a fixed distance and then emitting the flattop beam to act on the processing surface, and staying for a certain period of time each time to complete the welding work of the flattop beam at the position. Here, the fixed distance of movement can be the diameter of the irradiation area formed by the flattop beam on the target product. This mode can reduce energy consumption while ensuring that the processing track is processed as much as possible. Another mode is to always emit the flattop beam during the movement. This mode also needs to stay for a certain period of time each time to complete the welding work of the flattop beam at the position after moving a fixed distance. The fixed distance of movement can be the diameter of the irradiation area formed by the flattop beam on the target product. The process is basically the same as the previous one, except that there is more energy consumption during the movement. Based on the two working modes, it can be concluded that the fixed distance is essentially the distance from the center point of the second area to the center point of the third area, so the third area is the new second area. The second area is the irradiation area formed by the flattop beam on the target product, which is a real-time irradiation area. There can be only one second area at the same time, and the third area is calculated according to the second area. Whenever the second area changes, the third area also changes.

[0084] In an embodiment, the adjusting of the light intensity of the flattop beam acting on the target product according to the temperature changes of the second area and the third area comprises:

[0085] The temperature of the second region is identified by the temperature identification module to obtain a temperature contour map of the second region;

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

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

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

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

[0090] The temperature change rate K of the third region is obtained from (T2-T3) / t;

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

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

[0093] The real-time total power for generating the flat-top beam is adjusted according to the to-be-adjusted power, and 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 region, T2 is the cutoff temperature of the second region at the cutoff time of the residence time, T1 is the starting temperature of the second region at the starting time of the residence time, P is the real-time total power for generating the flat-top beam, A is the irradiation region of the flat-top beam formed on the target product, and T3 is the cutoff temperature of the third region at the cutoff time of the residence time.

[0095] In this embodiment, the step of monitoring the temperatures of the second region and the third region is the same as the step of monitoring the temperature of the first region.

[0096] In this embodiment, the corresponding relationship between the light intensity of the flat-top beam and the peak light intensity is The peak light intensity can be obtained from the integral light intensity In an ideal case, P=πR 2 I 0 , and the radius of the irradiation region of the flat-top beam formed on the target product is equal to the beam waist radius of the Gaussian beam, so A=πR 2 =πω 2 In an 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, so the light intensity I3 of the flat-top beam is determined from 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 from the original total power of the flat-top beam to obtain a new total power.

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

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

[0100] In the embodiment, the residence time of the flat-top beam in the second region can be obtained according to the residence time of the flat-top beam in the first second region, for example, the image recognition module recognizes the processing trace of the first second region welded by the flat-top beam, for example, recognizes the depth of the processing trace in the melting process, when the depth of the processing trace reaches the required depth, the flat-top beam is moved and the processing time of the flat-top beam on the first second region is calculated, which is the residence time of the flat-top beam in the second region. In addition to the image recognition module, the gas monitoring module can also be used to monitor the pressure and flow of the auxiliary gas to calculate the residence time.

[0101] In the 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, so for the third region, it is necessary to increase the temperature, only the amplitude of the temperature increase will change.

[0102] In the embodiment, T3 is not necessarily equal to T1, because the flat-top beam is moved to the third region, and during the movement, if the flat-top beam always emits, T3 can be greater than T1 but less than T2, if the flat-top beam only emits in the second region, due to heat dissipation and thermal effect, T3 can be less than T1.

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

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

[0105] corresponding the light intensity I3 and the temperature change rate k to form a plurality of data groups;

[0106] labeling all data groups on the coordinate system;

[0107] It is judged whether the number of data groups is 1, if yes, the corresponding relationship between the light intensity I3 and the temperature change rate k is calculated according to the origin of the coordinate system and the data group by using a linear regression equation, if not, the corresponding relationship between the light intensity I3 and the temperature change rate k is calculated according to all data groups by using a linear regression equation.

[0108] In the embodiment, when the number of data groups is 1, only the origin of the coordinate system can be used as the data group. With the increase of the number of data groups, the corresponding relationship between the light intensity I3 and the temperature change rate k is more accurate.

[0109] In the embodiment, the corresponding relationship between the light intensity I3 and the temperature change rate k is updated once for each data group generated.

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

[0111] A trajectory determination module is configured to identify a machining surface of the target product and determine a machining trajectory on each machining surface.

[0112] A first machining module is configured to, for each machining trajectory, generate a Gaussian light beam according to a preset light intensity, and preheat at a starting point of the machining trajectory by using the Gaussian light beam.

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

[0114] A light beam switching module is configured to judge whether the temperature of the first area reaches a preset temperature, and if yes, switch the Gaussian light beam to a flat-top light beam, and move the flat-top light beam along the machining trajectory to machine the target product.

[0115] An area identification module is configured to, before the flat-top light beam moves, mark an irradiation area formed by the flat-top light beam on the target product as a second area, and determine a next travel area of the flat-top light beam according to the second area and the machining trajectory, which is recorded as a third area.

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

[0117] In the embodiment, each module of the light beam intensity adjusting device for welding is modularized according to the method part of the present application. For specific explanations of each module, please refer to the corresponding content of the method part of the present application. The embodiment of the present application will not be described here again.

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

[0119] The laser emission module is connected with the control module, for generating a Gaussian beam;

[0120] The temperature identification module is connected with the control module, for identifying temperature;

[0121] The beam shaping module is connected with the control module, for transforming the Gaussian beam into a flat-top beam;

[0122] The control module is used for executing the steps of the welding beam intensity adjusting method.

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

[0124] This invention provides a laser welding machine that identifies the processing surface of a target product and determines the processing trajectory on each surface. For each processing trajectory, a Gaussian beam is generated based on a preset light intensity, and preheating is performed at the starting point of the processing trajectory using the Gaussian beam. The irradiation area formed by the Gaussian beam on the target product is marked as a first region, and the temperature of the first region is monitored. It is determined whether the temperature of the first region has reached a preset temperature. If so, the Gaussian beam is switched to a flat-top beam, and the flat-top beam is moved along 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 a second region. The next travel area of ​​the flat-top beam is determined based on the second region and the processing trajectory, and is marked as a third region. When the flat-top beam moves, the second and third regions 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 changes of the second and third regions. This approach involves preheating each processing trajectory with a Gaussian beam that has strong focusing ability and concentrated energy. Once the preset temperature is reached in the area affected by the Gaussian beam, the beam is switched to a flat-top beam with sharp edges and uniform energy distribution. As the flat-top beam moves, the light intensity of the beam on the target product is adjusted according to temperature changes to ensure consistent temperature and smooth processing marks. This solves the problem that laser welding machines cannot self-adjust the laser light intensity.

[0125] Figure 4 An internal structural diagram of the control module in one embodiment is shown. Figure 4 As shown, the control module includes a processor, a memory, a network interface, an input device, and a display screen connected via a system bus. The memory includes a non-volatile storage medium and internal memory. The non-volatile storage medium of the control module stores an operating system and may also store a computer program. When executed by the processor, this computer program enables the processor to implement a beam intensity adjustment method for welding provided in this embodiment of the invention. The internal memory may also store a computer program, which, when executed by the processor, enables the processor to execute the beam intensity adjustment method for welding provided in this embodiment of the invention. The display screen of the control module can be a liquid crystal display screen or an e-ink display screen. The input device of the control module can be a touch layer covering the display screen, or buttons, a trackball, or a touchpad provided on the control module's housing, or an external keyboard, touchpad, or mouse, etc.

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

[0127] In one embodiment, the beam intensity modulation device for welding provided by this invention can be implemented as a computer program, which can be implemented in the form of, for example... Figure 4 The control module shown operates on this device. The memory of the control module can store the various program modules that make up a beam intensity modulation device for welding, for example... Figure 2 The diagram shows a trajectory determination module, a first processing module, a temperature detection module, a beam switching module, a region identification module, and a beam intensity adjustment module. The computer program comprised of these modules causes the processor to execute the steps of a beam 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 can be used as follows Figure 2 The trajectory determination module in the beam intensity adjustment device for welding shown executes step S101; 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; and the control module can execute step S106 through the intensity adjustment module.

[0129] In one embodiment, a control module is provided, the control module including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to perform the following steps:

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

[0131] S102, For each processing trajectory segment, a Gaussian beam is generated according to the preset light intensity, and the Gaussian beam is used to preheat at the starting point of the processing trajectory segment.

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

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

[0134] S105, before the flat-top beam moves, marking an irradiation area formed by the flat-top beam on the target product as a second area, determining a next travel area of the flat-top beam according to the second area and the segment of the machining track, and recording the next travel area as a third area;

[0135] S106, updating the second area and the third area in real time while the flat-top beam moves, and adjusting the light intensity of the flat-top beam acting on the target product according to the temperature change of the second area and the third area.

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

[0137] S101, identifying a machining surface of a target product and determining a machining track on each machining surface;

[0138] S102, for each segment of the machining track, generating a Gaussian beam according to a preset light intensity, and using the Gaussian beam to preheat at a starting point of the segment of the machining track;

[0139] S103, 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;

[0140] 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 segment of the machining track to machine the target product;

[0141] S105, before the flat-top beam moves, marking an irradiation area formed by the flat-top beam on the target product as a second area, determining a next travel area of the flat-top beam according to the second area and the segment of the machining track, and recording the next travel area as a third area;

[0142] S106, updating the second area and the third area in real time while the flat-top beam moves, and adjusting the light intensity of the flat-top beam acting on the target product according to the temperature change 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 application are shown in sequence according to the arrows, the steps are not necessarily executed in the order indicated by the arrows. Unless otherwise specified herein, the execution of the steps is not strictly limited in sequence, and the steps can be executed in other sequences. Moreover, at least some of the steps in the embodiments can include a plurality of sub-steps or stages, which are not necessarily executed at the same time, but can be executed at different times, and the execution sequence of the sub-steps or stages is not necessarily sequential, but can be executed alternately or alternately with at least part of other steps or sub-steps or stages of other steps.

[0144] It can be understood by those skilled in the art that all or part of the processes in the above-mentioned embodiment methods can be completed by a computer program instructing related hardware, and 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 above-mentioned embodiments of each method. Any reference to memory, storage, database or other medium used in each embodiment provided by the present application can include non-volatile and / or volatile memory. Non-volatile memory can include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory can include random access memory (RAM) or external cache memory. As an illustration but not limitation, RAM is available in various 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] Any combination of the technical features of the above-mentioned embodiments can be combined. In order to make the description simple, all possible combinations of the technical features in the above-mentioned embodiments are not described, but as long as the combination of the technical features does not exist, it should be considered as the scope of the present application.

[0146] The above-mentioned embodiments only express several embodiments of the present application, and the description is more specific and detailed, but it should not be understood as limiting the scope of the present application. It should be noted that for those skilled in the art, without departing from the concept of the present application, a number of modifications and improvements can be made, which are within the scope of the present application.

Claims

1. A method of adjusting the light intensity of a light beam for welding, characterized in that The beam intensity adjustment method for welding comprises the following steps: S101, identifying the machining surface of the target product and determining the machining track on each machining surface; S102, for each machining track, generating a Gaussian beam according to a preset light intensity, and preheating at the starting point of the machining track using the Gaussian beam; 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 moving the flat-top beam along the machining track 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 a second area, and determining the next travel area of the flat-top beam according to the second area and the machining track, which is recorded as a third area; S106, updating the second area and the third area in real time while the flat-top beam moves, and adjusting 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.

2. The method of claim 1, wherein the step of adjusting the intensity of the light beam is performed by a controller. The method comprises the following steps: Obtaining the light intensity I1 corresponding to the melting of the material of the machining surface; Obtaining the preset light intensity I2 from 2*I1; By obtaining a 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; Moving the Gaussian beam to the starting point of the machining track and making the waist radius of the Gaussian beam equal to the radius of the irradiation area formed by the Gaussian beam on the target product, thereby preheating the starting point of the machining track; Where ω is the waist radius of the Gaussian beam.

3. The method of claim 1, wherein the step of adjusting the intensity of the light beam is performed by a controller. The method comprises the following steps: Identifying the temperature of the first area by a temperature identification 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; Taking the average value of the temperature of each contour area of the first area as the temperature of the first area.

4. The method of claim 1, wherein the step of adjusting the intensity of the light beam is performed by a controller. The method comprises the following steps: Controlling the Gaussian beam to pass through a beam shaping module to generate a flat-top beam; Setting the value n 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.

5. The method of claim 1, wherein the step of adjusting the intensity of the light beam is performed by a controller. The method comprises the following steps: Regularizing the second area into a circle, which is recorded as an initial circle; Determining the radius of the initial circle; Determining a concentric circle with a radius of 3r and the center of the initial circle as the center; Determining a circular ring where the initial circle and the concentric circle do not overlap, which is recorded as a to-be-determined area; Determining an area with the same shape as the initial circle in the area where the to-be-determined area and the machining track overlap, and determining the area as the next travel area of the flat-top beam, which is recorded as a third area.

6. The method of claim 1, wherein the step of adjusting the intensity of the beam of light is performed by a controller. The method comprises the following steps: determining whether the irradiation area formed by the flat-top beam on the target product overlaps with the third area, and if so, determining the third area as a new second area and deleting the old second area to keep only one second area during the movement of the flat-top beam; determining a next travel area of the flat-top beam according to the second area and the segment of the processing track, and recording the next travel area as a new third area; deleting the old third area to keep only one third area during the movement of the flat-top beam.

7. The method of claim 1, wherein the step of adjusting the intensity of the light beam is performed by a controller. The adjusting the light intensity of the flat-top beam on the target product according to the temperature change of the second area and the third area comprises: identifying the temperature of the second area by the temperature identification module to obtain a temperature contour map of the second area; monitoring the temperatures of the second area and the third area respectively; obtaining the temperature change rate k of the second area from (T2-T1) / t; determining the light intensity I3 of the flat-top beam from P / A; establishing a corresponding relationship between the light intensity I3 and the temperature change rate k; obtaining the to-be-changed rate K of the third area from (T2-T3) / t; obtaining the to-be-changed light intensity I4 by substituting the to-be-changed rate K into the corresponding coordinate system of the light intensity I3 and the temperature change rate k; obtaining the to-be-adjusted power from (I4-I3)*A; adjusting the real-time total power of the flat-top beam to further adjust the light intensity of the flat-top beam on the target product according to the to-be-adjusted power; wherein t is the residence time of the flat-top beam in the second area, T2 is the end temperature of the second area at the end time of the residence time, T1 is the start temperature of the second area at the start time of the residence time, P is the real-time total power of the flat-top beam, A is the irradiation area formed by the flat-top beam on the target product, and T3 is the end temperature of the third area at the end time of the residence time.

8. The method of claim 7, wherein the step of adjusting the intensity of the light beam is performed by a controller. The establishing the corresponding relationship between the light intensity I3 and the temperature change rate k comprises: establishing a coordinate system with the light intensity as the horizontal axis and the change rate as the vertical axis; corresponding the light intensity I3 and the temperature change rate k to form a plurality of data groups; labeling all the data groups on the coordinate system; determining whether the number of data groups is 1, if so, calculating the corresponding relationship between the light intensity I3 and the temperature change rate k according to the origin of the coordinate system and the data group by using a linear regression equation, and if not, calculating the corresponding relationship between the light intensity I3 and the temperature change rate k according to all the data groups by using a linear regression equation.

9. A light beam intensity adjusting device for welding, characterized by comprising: a light source; a light beam shaping device; a light beam intensity adjusting device; and a light beam shaping device. The light intensity adjusting device for welding comprises: a track determination module configured to identify processing surfaces of the target product and determine processing tracks on each processing surface; a first processing module configured to generate a Gaussian beam according to a preset light intensity for each segment of the processing track, and preheat at the start point of the segment of the processing track by using the Gaussian beam; a temperature detection module configured to mark an irradiation area formed by the Gaussian beam on the target product as a first area, and monitor the temperature of the first area; a light beam switching module configured to determine whether the temperature of the first area reaches a preset temperature, and if so, switch the Gaussian beam to a flat-top beam, and move the flat-top beam along the segment of the processing track to process the target product. The region identification module is configured to mark an irradiation region formed by the flat-top light beam on the target product as a second region before the flat-top light beam moves, and determine a next travel region of the flat-top light beam as a third region according to the second region and the segment of the processing track; The light intensity adjustment module is configured to update the second region and the third region 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 region and the third region.

10. A laser welding machine characterized by, The laser welding machine comprises a laser emission module, a temperature identification module, a light beam shaping module and a control module. The laser emission module is connected with the control module and is configured to generate a Gaussian light beam. The temperature identification module is connected with the control module and is configured to identify temperature. The light beam shaping module is connected with the control module and is configured to transform the Gaussian light beam into a flat-top light beam. The control module is configured to perform the steps of the light intensity adjustment method for the welding light beam according to any one of claims 1 to 8.

Images