Copper plate welding equipment

Abstract

The invention relates to the technical field of welding, in particular to red copper plate welding equipment which comprises a machine shell, a light reflecting plate, a heat source and a plurality of welding stations are arranged in the machine shell, and the welding stations are arranged in the vertical direction; a conveying assembly and a laser welding head are arranged at each welding station, the conveying assemblies are used for conveying two red copper plates in the transverse direction, and a welding seam is formed between the two red copper plates; the laser welding head is obliquely arranged and used for emitting laser to a welding seam, and the laser can be reflected to the red copper plate on the upper layer after being reflected by the red copper plates; the reflecting plate is arranged above the red copper plate on the uppermost layer and is used for reflecting the laser reflected from the red copper plate on the uppermost layer back to the red copper plate on the uppermost layer; and the heat source is used for heating the lowermost red copper plate. Therefore, the laser reflected by the red copper plate can be utilized, the red copper plate is heated, the temperature gradient between a welding seam and the red copper plate can be reduced, and the welding quality is improved.

Description

Technical Field

[0001] The invention relates to the technical field of welding, in particular to a copper plate welding device. Background Art

[0002] Red copper, also known as red copper, is an industrial pure copper named after its purple-red color. It is widely used in the industrial field because of its excellent electrical conductivity, ductility and thermal conductivity.

[0003] During industrial processing, copper can be formed into various forms, such as tubes and plates, through rolling and drawing, depending on specific usage requirements. Copper sheets are widely used in industries such as electrical engineering and construction. Welding is an essential process for connecting and shaping copper sheets.

[0004] With the development of welding technology, laser welding, with its advantages of high precision and high efficiency, has gradually been applied to the field of copper plate welding. For example, the laser welding equipment disclosed in Chinese patent application CN118559197A comprises a fixture, a laser, and a laser welding head. The fixture is used to fix the workpiece; the laser is used to output a composite beam for welding the workpiece. The composite beam consists of an annular beam and a central beam, with the central beam located within the annular beam; the laser welding head is used to converge the composite beam onto the workpiece and oscillate the composite beam, thereby achieving high-quality welding of thick copper materials.

[0005] However, existing laser welding equipment also has some problems in the process of welding copper plates: due to the high thermal conductivity and high reflectivity of copper plates (its initial reflectivity to lasers is as high as 80%-90%), the welding process has obvious energy loss problems: in the initial stage of welding, a large amount of laser energy is reflected from the surface of the copper plate into the external environment, causing serious energy waste. Even if the remaining laser energy successfully acts on the copper plate, due to its extremely high thermal conductivity, the heat will quickly diffuse to the surrounding area, making it difficult for the welding area to quickly reach the effective welding temperature. In order to meet the welding requirements, it is often necessary to increase the laser emission power, which not only greatly increases the energy consumption cost, but also puts higher requirements on the performance and life of the laser. Summary of the Invention

[0006] Based on this, it is necessary to provide a copper plate welding device to address the problem of poor welding quality in the current copper plate welding process.

[0007] The above purpose is achieved through the following technical solutions: A copper plate welding device, comprising a housing, wherein a reflector, a heat source and a plurality of welding stations are provided in the housing, wherein the plurality of welding stations are arranged in a vertical direction; a conveying assembly and a laser welding head are provided at each welding station, wherein the conveying assembly is configured to convey two copper plates in a horizontal direction, wherein a weld is formed between the two copper plates; the laser welding head is arranged at an angle and configured to emit a laser toward the weld, wherein the laser is reflected by the copper plates and then reflected onto the copper plates on the upper layer; the reflector is provided above the copper plate on the upper layer and configured to reflect the laser reflected from the copper plate on the upper layer back onto the copper plate on the upper layer; the heat source is configured to heat the copper plate on the lower layer.

[0008] Furthermore, initially, the laser welding head on the top layer has a first focus, and all other laser welding heads have a second focus, and the second focus is arranged lower than the first focus relative to the copper plate; two adjacent welds are grouped together, and when the weld located above reaches a preset temperature, the laser welding head corresponding to the weld located below is adjusted to switch from the second focus to the first focus.

[0009] Furthermore, the preset temperatures corresponding to the welds in different layers are different, and the preset temperatures increase from top to bottom.

[0010] Furthermore, each of the conveying assemblies includes multiple pairs of conveying rollers, which are arranged at intervals along the horizontal direction. The two conveying rollers in the same pair are jointly supported on the upper and lower sides of the same copper plate, and the conveying rollers can rotate around their own axes.

[0011] Furthermore, each of the conveying rollers is sleeved with two pushing rings, which can slide along the axial direction of the conveying roller. The two pushing rings on the same conveying roller respectively push on the outer walls of the two copper plates forming the same weld. Each pushing ring is connected to the casing through an elastic member. Under the action of the elastic member, the pushing ring has a tendency to push the copper plate inward.

[0012] Furthermore, the elastic member is a compression spring.

[0013] Furthermore, along the direction of conveying the copper plate, from back to front, the elastic coefficients of the compression springs located in the same layer increase successively.

[0014] Furthermore, the copper plate welding equipment also includes a distance adjustment mechanism, which is configured to adjust the distance between two adjacent copper plates in the vertical direction and the distance between the top copper plate and the reflective plate in inverse proportion according to the thickness of the copper plate; the laser welding head moves synchronously with the copper plate on its layer.

[0015] Furthermore, the pitch-adjusting mechanism includes multiple pairs of variable-pitch screws and multiple pairs of support seats, and the multiple pairs of variable-pitch screws are arranged at intervals along the horizontal direction, and the two variable-pitch screws of the same pair are respectively located on the outer sides of the two ends of the same conveying roller, and the variable-pitch screws are vertically arranged and have variable-pitch spiral grooves, and the pitch of the variable-pitch spiral grooves gradually increases from bottom to top; the multiple pairs of support seats are respectively arranged corresponding to the multiple conveying assemblies located in the middle, and the two support seats of the same pair are respectively rotatably sleeved on the two ends of all the conveying rollers of the same conveying assembly; the support seats are simultaneously sleeved on all the variable-pitch screws located on the same side, and a spiral fit is formed between the variable-pitch spiral groove and the variable-pitch screw; the reflector is simultaneously sleeved on all the variable-pitch screws, and a spiral fit is formed between the variable-pitch spiral groove and the variable-pitch screw.

[0016] Furthermore, an observation window is provided on the casing, and the observation window is configured to be able to view the welding status of the copper plate.

[0017] The beneficial effects of the present invention are: The present invention relates to a copper plate welding device. The device is provided with a plurality of welding stations arranged in a vertical direction, and a laser welding head is provided at each welding station, and a reflector is provided at the welding station on the uppermost layer. The linkage between the laser welding head, the copper plate and the reflector is utilized so that the laser can be reflected back and forth between the uppermost copper plate and the reflector and between two adjacent copper plates in the vertical direction, so that the laser originally reflected into the external environment by the copper plate can be utilized. While improving the laser utilization rate, the copper plate can be heated, and the temperature gradient between the weld and the copper plate can be reduced, so that the temperature of the welding area is more uniform, the generation of thermal stress is effectively reduced, and the risk of welding cracks is reduced. At the same time, the cooling rate of the molten pool can be slowed down, which helps to discharge gas, reduce the formation of pores, and is conducive to improving the welding quality.

[0018] Furthermore, by setting the laser welding head with a first focus and a second focus, and utilizing the characteristic that the second focus is set lower than the first focus relative to the copper plate, when the laser welding head has the first focus, the welding quality is guaranteed; when the laser welding head has the second focus, the laser reflected by the copper plate is more concentrated on the upper copper plate, thereby improving the heating efficiency of the upper copper plate.

[0019] Furthermore, by providing two push rings, and providing the two push rings so as to elastically abut against the outer side walls of the two copper plates forming the same weld, a pre-tightening force can be applied to the two copper plates forming the same weld, so that the two copper plates forming the same weld have a tendency to be tight, thereby resisting the thermal stress generated by welding of the copper plates, so that the weld formed by the two copper plates will not deviate too much, thereby ensuring the welding quality.

[0020] Furthermore, by setting the elastic coefficients of the compression springs located in the same layer to increase successively from back to front along the direction of conveying the copper plates, the thermal stress of the weld close to the laser welding head is large, and the thermal stress of the weld away from the laser welding head is small, thereby reducing the deflection of the two copper plates due to different thermal stresses, which is beneficial to ensuring the welding quality.

[0021] Furthermore, by setting up a distance adjustment mechanism, when facing a thicker copper plate, the distance between the two adjacent copper plates in the vertical direction and the distance between the top copper plate and the reflective plate are adjusted to be closer, so as to avoid excessive dispersion during laser reflection, thereby increasing the copper plate's absorption rate of the laser and improving the heating efficiency; when facing a thinner copper plate, the distance between the two adjacent copper plates in the vertical direction and the distance between the top copper plate and the reflective plate are adjusted to be farther, so that the laser is more dispersed, thereby reducing the copper plate's absorption rate of the laser and avoiding the problem of melting through. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A schematic diagram of the three-dimensional structure of the copper plate welding equipment provided by an embodiment of the present invention when welding copper plates; Figure 2 A schematic diagram of the cross-sectional structure of the copper plate welding equipment provided by the embodiment of the present invention when welding copper plates Figure 1 ; Figure 3 for Figure 2 A schematic diagram of the partially enlarged structure at W in the middle; Figure 4 A schematic diagram of the cross-sectional structure of the copper plate welding equipment provided by the embodiment of the present invention when welding copper plates Figure 2 ; Figure 5 A schematic diagram of the three-dimensional structure of the copper plate welding device provided by an embodiment of the present invention, without the observation window, when welding copper plates; Figure 6 for Figure 5 Schematic diagram of the partially enlarged structure at X in the middle; Figure 7 A schematic diagram of the front view of the copper plate welding device provided by an embodiment of the present invention, without the observation window, when welding copper plates; Figure 8 for Figure 7A schematic diagram of the partially enlarged structure at Y in the middle; Figure 9 for Figure 8 Middle AA section view; Figure 10 for Figure 7 Schematic diagram of the partially enlarged structure at Z in the middle; Figure 11 This is a diagram showing the working principle of the copper plate welding equipment provided in an embodiment of the present invention.

[0023] in: 1. Casing; 101. First chute; 102. Second chute; 103. Observation window; 104. Drive cylinder; 2. Reflector; 3. Electromagnetic heating unit; 4. Conveying assembly; 401. Conveying roller; 5. Laser welding head; 501. First focus; 502. Second focus; 503. Convergence point; 6. Push ring; 7. Compression spring; 8. Pitch adjustment mechanism; 801. Variable pitch screw rod; 802. Support seat; 8021. Fixed column; 8022. Transfer unit; 8023. Sliding unit; 80231. Third chute; 9. Copper plate. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below through embodiments and in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0025] The serial numbers assigned to components herein, such as "first," "second," etc., are used solely to distinguish the objects being described and do not convey any sequential or technical meaning. References to "connection" and "coupling" herein, unless otherwise specified, include both direct and indirect connections (couplings). In the description of the present invention, it should be understood that terms such as "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise" indicate positions or relationships based on those shown in the accompanying drawings. These terms are intended solely to facilitate the description of the present invention and simplify the description. They are not intended to indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on the present invention.

[0026] In the present invention, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediary. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0027] Refer to the following Figures 1 to 11 The copper plate welding device provided in the embodiment of the present invention is described below. The device is particularly suitable for welding the copper plate 9. Of course, it is also suitable for welding other plates with high thermal conductivity and high reflectivity.

[0028] In the existing field of laser welding of copper plates 9, lasers are usually used to weld the copper plates 9; however, in the initial stage of welding, a large amount of laser energy is reflected by the surface of the copper plates 9. Taking a welding power of 2000W as an example, the initial reflected energy can reach 1600-1800W, resulting in serious energy waste; even if the remaining energy successfully acts on the copper plates 9, due to their extremely high thermal conductivity, the heat will quickly diffuse to the surrounding area, making it difficult for the welding area to quickly reach the effective welding temperature. In order to meet the welding requirements, it is often necessary to increase the laser power to 1.5-2 times of the conventional welding power, which not only greatly increases the energy consumption cost, but also puts higher requirements on the performance and life of the laser. According to statistics, the unit energy consumption cost of using laser to weld copper plates 9 is 3-5 times higher than that of welding ordinary steel, which greatly limits the large-scale application and promotion of laser welding technology for copper plates 9.

[0029] Based on this, in the copper plate welding equipment provided in the embodiment of the present invention, it is configured to include a casing 1; a reflector 2 and a plurality of welding stations are arranged in the casing 1, wherein the plate surface of the reflector 2 is arranged horizontally and close to the top of the casing 1; the plurality of welding stations are arranged at intervals in the vertical direction to avoid interference; each welding station is provided with a conveying component 4 and a laser welding head 5, and the conveying component 4 is configured to be able to convey two copper plates 9 from back to front, the two copper plates 9 are arranged in the left and right directions, and a weld is formed between the two copper plates 9, and the plate surface of the copper plate 9 is set horizontally when being conveyed; openings are opened on the front and rear side walls of the casing 1 corresponding to the welding stations, and the openings are used to receive or discharge the copper plates 9; the laser welding head 5 is located at the front side of the welding station and is arranged close to the top. The laser welding head 5 extends downward and rearward as a whole and points to the copper plate 9, so as to facilitate the emission of laser to the weld for welding; the reflector 2 is located above the topmost copper plate 9. Exemplarily, the number of welding stations can be set to three and arranged at equal intervals in the vertical direction; accordingly, the number of conveying components 4 and laser welding heads 5 are respectively set to three, so that three pairs of copper plates 9 can be welded at one time.

[0030] When the laser welding head 5 emits a laser, the laser will be reflected when it hits the copper plate 9. For the top copper plate 9, the reflected laser will be reflected to the bottom of the reflective plate 2, and then reflected by the reflective plate 2, and then returned to the top copper plate 9 again, so that the top copper plate 9 can receive the laser emitted by the laser welding head 5 corresponding to the current layer and the laser reflected by the reflective plate 2. The reflective plate 2 can be made of a highly reflective material to ensure that the laser energy emitted by the laser welding head 5 on the top layer can be absorbed by the top copper plate 9 as much as possible; for the copper plates 9 on other layers, the laser can be reflected to the bottom of the upper copper plate 9 after being reflected by the copper plate 9. Thereby, the upper copper plate 9 can simultaneously receive the laser emitted by the laser welding head 5 corresponding to the current layer and the laser emitted by the laser welding head 5 corresponding to the lower layer. The sum of the two makes the laser energy absorbed by the copper plates 9 of other layers equivalent to the laser energy absorbed by the copper plate 9 of the uppermost layer; for the copper plate 9 of the lowermost layer, most of the energy carried by the laser reflected by it is absorbed by the penultimate copper plate 9, and there is no other reflected laser below it. In order to ensure that the energy absorbed by all copper plates 9 is equivalent, a heat source is also provided in the casing 1. The heat source can be set as an electromagnetic heating part 3, and is set at the lowest welding station and configured to heat the copper plate 9 of the lowermost layer.

[0031] Thus, through the synergistic effect of multiple welding stations arranged in a vertical direction, the laser welding head 5 at each welding station, the reflector 2 at the top welding station, and the heat source, a system for recycling laser energy and heating the copper plate 9 is constructed. This allows the laser energy that would otherwise be reflected to the outside world to be fully utilized, achieving heating of all the copper plates 9. This heating method makes the heat distribution in the welding area more uniform. When the laser energy is recycled and acts on the copper plate 9, the temperature difference between the weld area and the non-weld area is reduced, that is, the temperature gradient between the weld and the copper plate 9 is reduced. The reduction in temperature gradient reduces the thermal expansion difference caused by temperature unevenness within the material. During the welding process, when the laser leaves and the material in the weld area cools and contracts, the restraining effect of the surrounding material on it is weakened, thereby effectively reducing the generation of thermal stress and reducing the risk of welding cracks.

[0032] At the same time, due to the more uniform temperature in the weld area and the relatively stable overall temperature level, the cooling rate of the molten pool is slowed down. The slower cooling rate provides more time for the gas in the molten pool to escape, allowing the gas to be more fully discharged, thereby reducing the formation of pores. In summary, through the effective use of laser energy and the appropriate heating method, temperature uniformity is achieved, thermal stress and pores are reduced, and ultimately the welding quality of the copper plate 9 is improved.

[0033] Specifically, each conveying assembly 4 can be configured to include two conveyor belts, which are arranged at intervals along the left and right directions, and the conveyor belts extend horizontally along the front and back directions as a whole. Each conveyor belt is used to convey a copper plate 9 from back to front, so that the two copper plates 9 can be arranged at intervals to form a weld.

[0034] More specifically, in order to reduce the heat exchange between the copper plate 9 and the conveyor belt, a heat insulating layer is provided on the outer surface of the conveyor belt, and the material of the heat insulating layer can be set to ceramic fiber.

[0035] It is understood that the conveyor belt may also be replaced by a conveyor chain.

[0036] In a further embodiment, in order to further improve the heating efficiency of the copper plate 9, it is set that at the initial stage, the topmost laser welding head 5 has a first focus 501, and all other laser welding heads 5 have a second focus 502, and the second focus 502 is arranged lower than the first focus 501 relative to the copper plate 9, so that the laser reflected by the copper plate 9 is more concentrated on the upper layer of copper plate 9, thereby improving the heating efficiency of the upper layer of copper plate 9.

[0037] Specifically, if Figure 11As shown, the laser welding head 5 with the first focus 501 and the laser welding head 5 with the second focus 502 are at the same height and reflect the laser light toward the copper plate 9 located below along the same slope. Since the second focus 502 is arranged lower than the first focus 501 relative to the copper plate 9, the convergence point 503 of the laser light emitted by the laser welding head 5 with the second focus 502 after being reflected by the copper plate 9 located below is closer to the copper plate 9 located above than the convergence point 503 of the laser light emitted by the laser welding head 5 with the first focus 501 after being reflected by the copper plate 9 located below, thereby making the convergence point 503 of the laser light emitted by the laser welding head 5 with the second focus 502 closer to the copper plate 9 located above. The laser emitted by the laser welding head 5 is reflected by the copper plate 9 located below, and the diameter of the light spot formed on the copper plate 9 located above is d. The laser emitted by the laser welding head 5 with a second focus 502 is reflected by the copper plate 9 located below, and the diameter of the light spot formed on the copper plate 9 located above is D. D>d. Therefore, by adjusting all laser welding heads 5 except the top one to initially have the second focus 502, the laser reflected by the copper plate 9 is more concentrated on the copper plates 9 other than the top and bottom layers, which helps to improve the heating efficiency of the copper plates 9 other than the top and bottom layers.

[0038] And two adjacent welds are grouped together. When the upper weld reaches the preset temperature, the laser welding head 5 corresponding to the lower weld is adjusted to switch from the second focus 502 to the first focus 501 to ensure the welding quality of the lower weld, and thus ensure the welding quality of all welds.

[0039] In a further embodiment, in order to improve the overall welding efficiency, the preset temperatures corresponding to the welds in different layers are different, and the preset temperatures increase from top to bottom.

[0040] Specifically, taking the required heating temperature of the weld to be 200°C and there being three layers of welds as an example, the preset temperatures of the welds from top to bottom are set to 195°C and 198°C. When the top weld reaches 195°C, the middle laser welding head 5 is adjusted to switch from the second focus 502 to the first focus 501, so that the laser energy emitted by it mainly acts on the middle weld. At this time, the top laser welding head 5 itself has the first focus 501, so that the laser energy emitted by it mainly acts on the top weld; when the middle weld reaches 198°C, the heat source is turned off and the bottom is adjusted to switch from the second focus 502 to the first focus 501. The laser welding head 5 switches from the second focus 502 to the first focus 501, so that the laser energy it emits mainly acts on the bottom weld. At this time, the top weld also reaches almost 198°C. At the same time, under the heating action of the heat source, the bottom weld also reaches almost 198°C; since the three laser welding heads 5 all have the first focus 501, the laser energy received by the three welds can remain consistent, and the three welds can reach 200°C at the same time, so that the welding of the three welds can be started at the same time, avoiding waiting time, thereby improving the overall welding efficiency.

[0041] In other embodiments, each conveying assembly 4 can also be configured to include multiple pairs of conveying rollers 401, which extend horizontally in the left-right direction, and both ends are rotatably inserted into the housing 1. Multiple pairs of conveying rollers 401 are arranged side by side and at intervals in the front-to-back direction, and the two conveying rollers 401 of the same pair are arranged side by side and at intervals in the up-down direction, and are jointly supported on the upper and lower sides of the same copper plate 9. When the conveying rollers 401 rotate, they can drive the copper plate 9 to move from back to front through friction contact between them and the copper plate 9.

[0042] It can be understood that, in order to provide driving force for the conveying roller 401 to rotate, the conveying assembly 4 is configured to further include a first driving member.

[0043] It is understood that the first driving member can be configured as a driving motor or a hydraulic motor. For example, if the first driving member is configured as a driving motor, the driving motor is mounted on the housing 1 , and the motor shaft is coaxially and fixedly connected to one of the two conveyor rollers 401 in the same pair, ensuring that the motor can rotate about its own axis, thereby driving the copper plate 9 from rear to front through the follow-up movement of the other conveyor roller 401.

[0044] In a further embodiment, copper itself has an extremely high thermal conductivity. Under the influence of the welding heat source, a significant temperature gradient forms between the weld and non-weld areas. When the laser locally heats the copper plate 9, the weld and the surrounding material rapidly heat up and expand, while areas away from the weld remain relatively cool due to faster heat dissipation. This uneven temperature distribution leads to differential thermal expansion within the material. As the welding process progresses, after the laser is removed, the material in the weld area begins to cool and contract. At this time, the cooled surrounding material constrains the shrinking weld area, causing the weld area to experience tensile stress while the surrounding areas may experience compressive stress. Because copper's strength decreases at high temperatures and the local temperature change rate is extremely rapid during welding, the interaction of these tensile and compressive stresses can easily induce plastic deformation of the material. Under the continued action of thermal stress, the weld will deform. This deformation may manifest as a shortening in length due to longitudinal contraction, a change in width due to lateral contraction, or angular or wavy deformation caused by uneven stress distribution.

[0045] Based on this, in the copper plate welding equipment provided in the embodiment of the present invention, it is configured that two push rings 6 are sleeved on each conveyor roller 401, and the two push rings 6 are arranged at intervals in the left and right directions. Under the axial guidance of the conveyor roller 401, the push ring 6 can slide along the axial direction of the conveyor roller 401. The push ring 6 on the left side of the same conveyor roller 401 pushes on the left side wall of the copper plate 9 on the left side forming the same weld, and the push ring 6 on the right side pushes on the right side wall of the copper plate 9 on the right side forming the same weld. On the right side wall, each push ring 6 is connected to the housing 1 via an elastic member, which can be configured as a compression spring 7. During installation, the compression spring 7 is sleeved onto the conveyor roller 401. Under the action of the compression spring 7, the push ring 6 can rotate relative to the conveyor roller 401, thereby avoiding affecting the rotation of the conveyor roller 401 and pushing against the copper plate 9. It also tends to push the copper plate 9 inward, thereby applying a preload force to the two copper plates 9 forming the same weld. When thermal stress attempts to deform the weld, the preload force resists this deformation. For example, if the weld shrinks longitudinally due to thermal stress, resulting in a shortening in length, or shrinks laterally due to width change, the preload force will hinder this contraction. It will also inhibit angular or wavy deformation. In this way, the preload force interacts with the thermal stress, offsetting or weakening the effect of thermal stress on the weld, preventing the weld formed by the two copper plates 9 from deviating too much, thereby ensuring weld quality.

[0046] In a further embodiment, in order to further improve the welding quality of the weld, it is set that the elastic coefficient of the compression spring 7 located in the same layer increases from back to front along the direction of conveying the copper plate 9. This is set because for the same weld, from front to back, as it gradually moves away from the laser welding head 5, its temperature gradually decreases and the thermal stress gradually decreases. When the elastic coefficient of the compression spring 7 remains unchanged, for the front weld portion, the preload force provided by the compression spring 7 through the push ring 6 may be sufficient or insufficient. For the rear weld portion, the preload force provided by the compression spring 7 through the push ring 6 may be excessive, causing the weld to be further deformed, thereby further reducing the welding quality of the weld. And the elastic coefficient of the compression spring 7 located in the same layer increases from back to front along the direction of conveying the copper plate 9. The coefficients increase successively. When the weld is deformed, for the front weld portion, it corresponds to the compression spring 7 with a larger elastic coefficient, and the compression spring 7 provides a larger pre-tightening force through the push ring 6, so that it can adapt to the situation where the weld is close to the laser welding head 5 and the thermal stress is large. For the rear weld portion, it corresponds to the compression spring 7 with a smaller elastic coefficient, and the compression spring 7 provides a smaller pre-tightening force through the push ring 6, so that it can adapt to the situation where the weld is far away from the laser welding head 5 and the thermal stress is small, thereby reducing the deflection of the two copper plates 9 due to different thermal stresses, which is beneficial to ensuring the welding quality.

[0047] It should be noted that in order to ensure that the compression springs 7 of the same layer initially exert the same pre-tightening force on the two copper plates 9 forming the same weld, the compression springs 7 at different positions can be adjusted to have different compression amounts. Specifically, the spring with a larger elastic coefficient has a smaller compression amount, and the spring with a smaller elastic coefficient has a larger compression amount, thereby ensuring that the compression springs 7 of the same layer initially exert the same pre-tightening force on the two copper plates 9 forming the same weld.

[0048] In other embodiments, the elastic member can also be set as a rubber matrix, which is connected between the push ring 6 and the casing 1 during installation. Under the action of the rubber matrix, the push ring 6 has a tendency to move inward, so that the two copper plates 9 forming the same weld can be tightened, thereby resisting the thermal stress generated by welding of the copper plates 9, so that the weld formed by the two copper plates 9 will not deviate too much, thereby ensuring the welding quality.

[0049] Similarly, in order to adapt to the situation where the thermal stress of the weld is large near the laser welding head 5 and the thermal stress is small far away from the laser welding head 5, it can be set to increase the size of the rubber matrix (such as diameter, cross-sectional area, etc.) located in the same layer from back to front along the direction of conveying the copper plate 9. When the weld is deformed, for the front weld part, it corresponds to a rubber matrix with a larger size, and the pre-tightening force provided by the rubber matrix through the push ring 6 is greater, thereby being able to adapt to the situation where the thermal stress of the weld is large near the laser welding head 5. For the rear weld part, it corresponds to a rubber matrix with a smaller size, and the pre-tightening force provided by the rubber matrix through the push ring 6 is smaller, thereby being able to adapt to the situation where the thermal stress of the weld is small far away from the laser welding head 5, thereby reducing the deflection of the two copper plates 9 due to different thermal stresses, which is beneficial to ensuring the welding quality.

[0050] In other embodiments, the thickness difference of the copper plate 9 will directly affect the energy demand and heat conduction characteristics during the welding process: for thicker copper plates 9, the heat capacity of the material itself is larger, and the heat conduction path in the internal part is longer. When the laser energy acts on its surface, the heat will quickly diffuse to the deep layer and the surrounding area of ​​the plate; if the laser energy is insufficient, it is difficult for the weld area to reach the temperature threshold required for effective welding in a short time, resulting in insufficient penetration, low penetration rate, and even defects such as unwelded joints; therefore, more laser energy is required to compensate for the heat loss of the thick plate, ensure that the heat can penetrate to the required depth, and form a sufficient molten pool to ensure the mechanical properties of the weld joint.

[0051] The thinner copper plate 9 has a small heat capacity, a short heat conduction path and a fast heat dissipation speed. However, due to the weak thermal barrier ability in the thickness direction of the plate, if the laser energy is too much, the temperature in the weld area will rise sharply. After exceeding the melting point of the material, it is very easy for the molten pool to collapse or even melt through. Melt through will not only destroy the integrity of the plate, but also cause the loss of weld metal and form hole defects, which seriously affect the welding quality and the safety of the component. Therefore, when welding the thin copper plate 9, the laser energy needs to be controlled within a reasonable range to ensure that the weld area is fully melted to achieve metallurgical bonding, while avoiding the problem of plate melt through caused by excess energy.

[0052] Based on this, in the copper plate welding equipment provided in the embodiment of the present invention, the copper plate welding equipment is configured to further include a distance adjusting mechanism 8, which is configured to be able to adjust the distance between the two adjacent copper plates 9 and the distance between the top copper plate 9 and the reflective plate 2 in inverse proportion according to the thickness of the copper plate 9, so that when facing a thicker copper plate 9, the distance between the two adjacent copper plates 9 in the vertical direction and the distance between the top copper plate 9 and the reflective plate 2 are adjusted to be closer. On the one hand, it avoids excessive dispersion when the laser is reflected, and on the other hand, it increases the number of reflections of the laser between the two, thereby increasing the absorption rate of the copper plate 9 to the laser and improving the heating efficiency; when facing a thinner copper plate 9, the distance between the two adjacent copper plates 9 in the vertical direction and the distance between the top copper plate 9 and the reflective plate 2 are adjusted to be farther, while making the laser more dispersed, reducing the number of reflections of the laser between the two, thereby reducing the absorption rate of the copper plate 9 to the laser and avoiding the problem of melt-through. The laser welding head 5 moves synchronously with the copper plate 9 on the layer where it is located, ensuring that the laser welding head 5 and the copper plate 9 are relatively stationary, thereby ensuring the stability of the laser welding head 5 during welding.

[0053] Specifically, the pitch-adjusting mechanism 8 is configured to include multiple pairs of variable-pitch screw rods 801 and multiple pairs of support seats 802. The multiple pairs of variable-pitch screw rods 801 are arranged side by side and at intervals in the front-to-back direction. The two variable-pitch screw rods 801 of the same pair are arranged at intervals in the left-right direction and are respectively located on the outside of both ends of the same conveying roller 401. The variable-pitch screw rods 801 are arranged vertically, and variable-pitch spiral grooves are opened on the circumferential side walls. The pitch of the variable-pitch spiral grooves gradually increases from bottom to top; multiple pairs of support seats 802 are arranged in the up-down direction and are respectively corresponding to the multiple conveying assemblies 4 located in the middle, the two support seats 802 of the same pair are arranged at intervals in the left-right direction, and the support seat 802 on the left side is rotatably sleeved on the left end portion of all the conveying rollers 401 of the same conveying assembly 4, and the support seat 802 on the right side is rotatably sleeved on the right end portion of all the conveying rollers 401 of the same conveying assembly 4; The left and right side walls of the casing 1 are provided with multiple sections of first sliding grooves 101, which extend in the vertical direction; a sliding member is provided on the outer side wall of the support seat 802, which can be set as a block structure and can slide along the first sliding groove 101. When the support seat 802 on the left side is installed, the sliding member passes through the first sliding groove 101 and is sleeved on all the variable pitch screw rods 801 on the left side, and a spiral fit is formed between the variable pitch spiral groove and the variable pitch screw rod 801. When the support seat 802 on the right side is installed, the sliding member passes through the first sliding groove 101 and is sleeved on all the variable pitch screw rods 801 on the right side, and a spiral fit is formed between the variable pitch spiral groove and the variable pitch screw rod 801; the reflector 2 is simultaneously sleeved on all the variable pitch screw rods 801, and a spiral fit is formed between the variable pitch spiral groove and the variable pitch screw rod 801. The laser welding head 5 can be fixed on the support seat 802 to ensure that the laser welding head 5 moves synchronously with the copper plate 9 on its layer, thereby ensuring that the laser welding head 5 and the copper plate 9 can be relatively still to avoid affecting the welding process.

[0054] When facing a thicker copper plate 9, all the variable pitch screw rods 801 are rotated in the opposite direction. The variable pitch screw rods 801 drive the reflector 2 and all the support seats 802 to move downward through the spiral cooperation between the support seat 802 and the reflector 2. Since the pitch of the variable pitch spiral groove gradually increases from bottom to top, the reflector 2 and the adjacent support seats 802 are close to each other. The support seat 802 synchronously drives the copper plate 9 to move through the conveying roller 401, so that the distance between the two adjacent copper plates 9 in the vertical direction and the distance between the top copper plate 9 and the reflector 2 are closer. On the one hand, it avoids excessive dispersion during laser reflection, and on the other hand, it increases the number of laser reflections between the two, thereby increasing the absorption rate of the copper plate 9 to the laser and improving the heating efficiency.

[0055] Similarly, when facing a thinner copper plate 9, all the variable pitch screw rods 801 are rotated in the forward direction. The variable pitch screw rods 801 drive the reflector 2 and all the support seats 802 to move upward through the spiral cooperation between the support seat 802 and the reflector 2. Since the pitch of the variable pitch spiral groove gradually increases from bottom to top, the reflector 2 and the adjacent support seats 802 are set away from each other. The support seat 802 synchronously drives the copper plate 9 to move through the conveying roller 401, thereby making the distance between the two adjacent copper plates 9 in the vertical direction and the distance between the top copper plate 9 and the reflector 2 farther. While making the laser more dispersed, the number of laser reflections between the two is reduced, thereby reducing the absorption rate of the copper plate 9 to the laser and avoiding the problem of melting through.

[0056] It can be understood that, in order to provide driving force for the variable pitch screw rod 801 to rotate, the pitch adjustment mechanism 8 is configured to further include a second driving member.

[0057] It is understood that the second driving member can be configured as a driving motor or a hydraulic motor. Taking the second driving member as an example, the driving motor is disposed on the housing 1, and the motor shaft and the bottom end of the variable pitch screw 801 are coaxial and fixedly connected, ensuring that the variable pitch screw 801 can be driven to rotate about its own axis. The distance between two adjacent copper plates 9 in the vertical direction and the distance between the top copper plate 9 and the reflector 2 can be adjusted by the screw fit between the variable pitch screw 801, the support base 802, and the reflector 2.

[0058] Exemplarily, the number of variable pitch screw rods 801 can be set to four, wherein two variable pitch screw rods 801 are located on the left side of the conveying roller 401, and are arranged side by side and at intervals in the front-to-back direction, and the other two variable pitch screw rods 801 are located on the right side of the conveying roller 401, and are arranged side by side and at intervals in the front-to-back direction, and the two variable pitch screw rods 801 on different sides are set correspondingly.

[0059] Exemplarily, the number of support seats 802 can be set to six, of which three support seats 802 are located on the left side of the conveying roller 401, and are arranged in parallel and at intervals in the up and down directions, and the other three support seats 802 are located on the right side of the conveying roller 401, and are arranged in parallel and at intervals in the up and down directions. The three support seats 802 on different sides are set correspondingly.

[0060] In an embodiment including a compression spring 7 and a distance adjustment mechanism 8 with different elastic coefficients, the two ends of the compression spring 7 are respectively connected between the push ring 6 and the support seat 802 during installation. In order to ensure the quality of welding, it is set so that the ratio of the increase in the pitch of the variable pitch spiral groove increases from back to front along the moving direction of the copper plate 9. The reason for this setting is that when the distance between two adjacent copper plates 9 in the vertical direction and the distance between the top copper plate 9 and the reflective plate 2 change, the number of reflections of the laser is uncertain, which makes it difficult to control the temperature increase of the copper plate 9 and the thermal expansion of the copper plate 9. The copper plate 9 is easily deformed uncontrollably under the push of the compression spring 7, which affects the welding quality. After the ratio of the increase in the pitch of the variable pitch spiral groove increases from back to front along the moving direction of the copper plate 9, during the rotation of the variable pitch screw rod 801, The moving speed of the copper plate 9 on one side close to the laser welding head 5 is made greater than the moving speed on the other side, so that the copper plate 9 is set at an angle. At this time, an eight-shaped structure is formed between the two adjacent layers of copper plates 9 in the vertical direction and between the top copper plate 9 and the reflective plate 2, thereby ensuring that the laser has a consistent number of reflections between the two adjacent layers of copper plates 9, thereby ensuring that the thermal stress changes of different layers of copper plates 9 are consistent, and ensuring that the compression springs 7 with different elastic coefficients in the same layer can be used in the process of welding copper plates 9 of different thicknesses, thereby improving applicability.

[0061] Specifically, multiple sections of second slide grooves 102 are correspondingly provided on the left and right side walls of the housing 1. The second slide grooves 102 are of arc-shaped structure, and the inner arc surface of the second slide grooves 102 is arranged to face backward. A fixed column 8021 is vertically and fixedly provided on the outer wall of the support seat 802. The fixed column 8021 passes through the second slide groove 102 and can slide along the second slide groove 102. A sliding portion 8023 is spirally sleeved on the variable pitch screw rod 801. A third slide groove 80231 is provided on the inner wall of the sliding portion 8023. The third slide groove 80231 extends horizontally in the front-to-back direction. A transfer portion 8022 is rotatably sleeved on the fixed column 8021. The outer end of the transfer portion 8022 is slidably clamped in the third slide groove 80231. Under the cooperation between the fixed column 8021, the transfer portion 8022 and the sliding portion 8023, the front end of the support seat 802 can move along the arc track, thereby changing the pitch of the screw rod 801. During the rotation of the pitch screw rod 801, the pitch of the variable-pitch spiral groove increases successively from back to front in the moving direction of the copper plate 9, so that the moving speed of the copper plate 9 on the side close to the laser welding head 5 is greater than the moving speed on the other side, thereby making the copper plate 9 tilted. At this time, an eight-shaped structure is formed between the two adjacent layers of copper plates 9 in the vertical direction and between the top copper plate 9 and the reflective plate 2, thereby ensuring that the laser has a consistent number of reflections between the two adjacent layers of copper plates 9, thereby ensuring that the thermal stress changes of different layers of copper plates 9 are consistent, and ensuring that the compression springs 7 with different elastic coefficients in the same layer can be used in the process of welding copper plates 9 of different thicknesses, thereby improving applicability.

[0062] More specifically, the fixed column 8021 corresponding to the first sliding groove 101 is fixedly connected to the transfer portion 8022 , and the outer end of the transfer portion 8022 is configured to be rotatably inserted into the sliding portion 8023 to avoid affecting the rotation of the support seat 802 .

[0063] In other embodiments, an opening is provided on the left side wall of the housing 1 , and an observation window 103 is provided at the opening. The observation window 103 is configured to be able to view the welding condition of the copper plate 9 .

[0064] In a further embodiment, in order to facilitate opening of the observation window 103 , the top of the observation window 103 may be configured to be hinged on the housing 1 .

[0065] In a further embodiment, in order to realize automatic opening and closing of the observation window 103, two driving cylinders 104 are symmetrically arranged on the front and rear side walls of the casing 1. The output shaft of the driving cylinder 104 is horizontally arranged to the left and is hinged on the observation window 103. When the output shaft of the driving cylinder 104 is extended, it is convenient to open the observation window 103. When the output shaft of the driving cylinder 104 is retracted, it is convenient to close the observation window 103.

[0066] It is understandable that the driving cylinder 104 can be configured as any one of a hydraulic cylinder, a pneumatic cylinder or an electric cylinder.

[0067] In other embodiments, in order to avoid direct contact between the conveying roller 401 and the weld, which would affect the shape of the weld, the conveying roller 401 is configured to have a structure with a large diameter at both ends and a small diameter in the middle.

[0068] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, 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, they should be considered to be within the scope of this specification.

[0069] The above-described embodiments merely illustrate several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present invention. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, and all such variations and improvements fall within the scope of protection of the present invention.

Claims

1. A copper plate welding device, characterized in that: The copper plate welding equipment includes a casing, in which a reflector, a heat source and multiple welding stations are arranged in a vertical direction; each welding station is provided with a conveying assembly and a laser welding head, and the conveying assembly is configured to convey two copper plates in the horizontal direction, and a weld is formed between the two copper plates; the laser welding head is arranged at an angle and is configured to emit a laser toward the weld, and the laser is reflected by the copper plate and then reflected onto the copper plate on the upper layer; the reflector is arranged above the uppermost copper plate and is configured to reflect the laser reflected from the uppermost copper plate back onto the uppermost copper plate; the heat source is configured to heat the lowermost copper plate.

2. The copper plate welding equipment according to claim 1, characterized in that: Initially, the laser welding head on the top layer has a first focus, and all other laser welding heads have a second focus, and the second focus is arranged lower than the first focus relative to the copper plate; two adjacent welds are grouped together, and when the weld located above reaches a preset temperature, the laser welding head corresponding to the weld located below is adjusted to switch from the second focus to the first focus.

3. The copper plate welding equipment according to claim 2, characterized in that: The preset temperatures corresponding to the welds in different layers are different, and the preset temperatures increase from top to bottom.

4. The copper plate welding equipment according to claim 1, characterized in that: Each of the conveying assemblies includes multiple pairs of conveying rollers, which are arranged at intervals in the transverse direction. The two conveying rollers in the same pair are jointly supported on the upper and lower sides of the same copper plate, and the conveying rollers can rotate around their own axes.

5. The copper plate welding equipment according to claim 4, characterized in that: Two push rings are sleeved on each of the conveying rollers, and the push rings can slide along the axial direction of the conveying roller. The two push rings on the same conveying roller respectively push on the outer side walls of the two copper plates forming the same weld. Each push ring is connected to the casing through an elastic member. Under the action of the elastic member, the push ring has a tendency to push the copper plate inward.

6. The copper plate welding equipment according to claim 5, characterized in that: The elastic member is a compression spring.

7. The copper plate welding equipment according to claim 6, characterized in that: Along the direction of conveying the copper plate, from back to front, the elastic coefficients of the compression springs located in the same layer increase successively.

8. The copper plate welding equipment according to claim 4, characterized in that: The copper plate welding equipment also includes a distance adjustment mechanism, which is configured to adjust the distance between two adjacent copper plates in the vertical direction and the distance between the top copper plate and the reflective plate in inverse proportion according to the thickness of the copper plate; the laser welding head moves synchronously with the copper plate on its layer.

9. The copper plate welding equipment according to claim 8, characterized in that: The pitch-adjusting mechanism includes multiple pairs of variable-pitch screws and multiple pairs of support seats. The multiple pairs of variable-pitch screws are arranged at intervals along the horizontal direction. The two variable-pitch screws of the same pair are respectively located on the outer sides of the two ends of the same conveying roller. The variable-pitch screws are vertically arranged and each has a variable-pitch spiral groove. The pitch of the variable-pitch spiral groove gradually increases from bottom to top; the multiple pairs of support seats are respectively arranged corresponding to the multiple conveying assemblies located in the middle, and the two support seats of the same pair are rotatably sleeved on the two ends of all the conveying rollers of the same conveying assembly; the support seats are simultaneously sleeved on all the variable-pitch screws located on the same side, and a spiral fit is formed between the variable-pitch spiral groove and the variable-pitch screw; the reflector is simultaneously sleeved on all the variable-pitch screws, and a spiral fit is formed between the variable-pitch spiral groove and the variable-pitch screw.

10. The copper plate welding equipment according to claim 1, characterized in that: The housing is provided with an observation window, and the observation window is configured to be able to view the welding condition of the copper plate.

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