Laser heating continuous stamping die and method of adjusting production

Abstract

A kind of laser heating continuous stamping die and adjusting production method, including upper die, lower die, laser heater, wherein lower die is provided with mirror, laser heater is separately arranged with upper die, lower die;When continuous stamping die works, material belt is arranged between upper die and lower die, upper die and lower die do relative opening and closing movement, material belt cooperates with the relative opening and closing between upper die and lower die, to set step distance and move forward, in turn enter next work station;Wherein before bending work station, material belt heating work station is provided;In material belt heating work station, laser heater emits laser, laser is reflected on material belt bending area by mirror and is heated, improve the plasticity and deformation resistance of bending area aluminum material, reduce the stress of copper-aluminum bonding layer in bending process, so as to solve the problem of aluminum material tearing or bonding layer cracking in the bending process of copper-aluminum composite plate in stamping production process due to small bending R angle, further product production yield.

Description

Technical Field

[0001] This invention relates to the field of metal parts stamping production equipment and process technology, specifically to a laser-heated continuous stamping die and an adjustment production method. Background Technology

[0002] Copper-aluminum composite sheets are made by metallurgically bonding copper and aluminum layers, combining the excellent electrical and thermal conductivity of copper with the lightweight and low-cost advantages of aluminum. Compared with traditional pure copper sheets, copper-aluminum composite sheets maintain high conductivity while offering advantages in weight and cost, making them a crucial supporting material for my country's "copper-saving with aluminum" strategy. Currently, this material is widely used in key conductive components in fields such as power electrical and transmission distribution, new energy vehicles, and new energy power generation, including busbars, battery connectors, busbars, and terminals.

[0003] In the field of new energy vehicles, copper-aluminum composite sheets are widely used in the stamping production of electric vehicle terminals. These terminals typically undergo bending forming processes to meet specific installation and connection requirements. However, in actual production, it has been found that during the bending process of copper-aluminum composite sheets, due to the poor plasticity of aluminum and low interfacial bonding strength, the outer surface of the aluminum layer is prone to tearing, or the copper-aluminum bonding layer may crack, leading to product defects. Current solutions to this problem involve increasing the radius of curvature (R-angle) in the bending area to reduce the maximum local strain experienced by the material during bending, thereby reducing the risk of tearing on the outer surface of the aluminum layer or cracking of the copper-aluminum bonding layer.

[0004] However, in some customer products, due to installation space constraints or fit requirements, the bending area must maintain a small radius (R-angle). Therefore, in actual stamping production, it is impossible to improve the problem of tearing on the outer surface of the aluminum layer or cracking of the copper-aluminum bonding layer during the forming process by increasing the R-angle. In this case, aluminum tearing and bonding layer cracking have become technical problems that the industry currently cannot solve. Therefore, there is an urgent need to develop a new technology that is not limited by the customer's product structure and can effectively improve the local forming performance of copper-aluminum composite sheets and avoid bending cracking without modifying the product structure. Summary of the Invention

[0005] To overcome the shortcomings in the prior art, this invention discloses a laser-heated continuous stamping die and an adjustment production method to solve the problem of aluminum tearing or bonding layer cracking during the bending process of copper-aluminum composite sheets due to the small bending radius.

[0006] To achieve the aforementioned objective, the present invention employs the following technical solution: a laser-heated continuous stamping die, comprising an upper die and a lower die, wherein the upper and lower dies perform relative opening and closing movements; further comprising a laser heater separately disposed from the upper and lower dies, and a reflector assembly disposed on the lower die, wherein the laser heater is provided with an X-axis and Y-axis dual galvanometer system, the separation design of the laser heater from the upper and lower dies is used to solve the influence of production vibration on the galvanometers in the laser heater; when the continuous stamping die is working, the strip is disposed between the upper and lower dies, and moves forward by a set step distance synchronously between the upper and lower dies, sequentially entering the next work station; and synchronously with the relative opening and closing movement between the upper and lower dies, the laser heater emits laser light, which is reflected by the reflector assembly onto a set area of ​​the strip for localized heating.

[0007] Furthermore, a signal triggering device is provided on the continuous stamping die, and the signal triggering device is electrically connected to the laser heater.

[0008] Furthermore, the lower mold includes a lower template and a lower mold frame, with light path holes extending through the lower template and lower mold frame; a reflector assembly is fixedly installed at the lower part of the lower mold frame, corresponding to the light path holes.

[0009] Furthermore, a water-cooling channel is provided in the reflector assembly.

[0010] Furthermore, the laser heater includes a laser head, a field lens is provided on the laser head, and a red laser indicator beam is provided in the laser head coaxially with the laser emission direction; a linear red laser indicator is provided on the laser head; and an angle is provided between the axis of the laser indicator and the axis of the field lens.

[0011] Furthermore, the laser heater operates with a green laser with a wavelength of 532nm.

[0012] Furthermore, the laser heater emits power between 2500W and 3000W.

[0013] Furthermore, the continuous stamping die also includes a laser adjustment plate for optical path adjustment and alignment; when the continuous stamping die is fixedly mounted on the stamping machine, the laser adjustment plate is used to adjust the distance between the laser head and the continuous stamping die, as well as the position of the laser irradiation on the strip; the laser adjustment plate is a frosted glass plate or a transparent plastic plate; the laser adjustment plate is provided with a focusing / alignment reference line and heating area adjustment marks.

[0014] A method for adjusting a laser-heated continuous stamping die specifically includes the following steps: S1. Installation of mold and laser heater: The upper mold is fixedly mounted on the lower part of the punch press slide by a pressure plate; the lower mold is fixedly mounted on the upper part of the punch press worktable by a pressure plate; the laser heater is fixedly mounted on the front of the punch press; the red laser indicator light emitted by the laser head is perpendicular to the punch press worktable in the initial state. S2. Adjustment of the initial position of the laser heater: Start the stamping machine, open the upper and lower dies, and place the laser adjustment plate on the upper end face of the optical path hole of the lower die; first, adjust the horizontal and vertical position of the laser head so that the red laser indicator spot coincides with the origin of the focusing / alignment reference line of the laser adjustment plate; adjust the distance between the laser head and the lower die so that the linear laser emitted by the laser indicator coincides with the horizontal line of the focusing / alignment reference line of the laser adjustment plate; S3. Adjust the laser heating position on the strip: In the laser heater, the scanning range of the red laser indicator light emitted by the laser head is set to coincide with the heating area adjustment mark on the laser adjustment plate; S4. Set the laser heater operating parameters to complete the adjustments before the production of continuous stamping die for copper-aluminum composite material laser heating; the laser heater operating parameters include output power, heating time, and start-up delay time.

[0015] A method for producing continuous stamping dies using laser heating involves adding a heating station before the bending station when producing copper-aluminum composite material parts using a continuous stamping die. At the heating station, the bending area is locally heated to between 150°C and 200°C using laser heating, which improves the plasticity of the aluminum material in the bending area and reduces the deformation resistance; at the same time, it avoids excessive temperature rise of the continuous stamping die as a whole.

[0016] Due to the adoption of the above-described technical solution, the present invention has the following beneficial effects: The laser-heated continuous stamping die disclosed in the present invention includes an upper die, a lower die, and a laser heater. A reflector is provided on the lower die. The laser heater is separately disposed from the upper and lower dies and is fixedly disposed at the front end of the stamping machine. The separation design of the laser heater from the upper and lower dies is used to solve the influence of production vibration on the galvanometer in the laser heater. When the continuous stamping die is working, the strip is placed between the upper and lower dies. The upper and lower dies perform relative opening and closing movements. The strip moves forward with a set step distance in coordination with the relative opening and closing of the upper and lower dies, and enters the next station in sequence. A strip heating station is provided before the bending station. At the strip heating station, the laser heater emits laser light, which is reflected by the reflector onto the strip setting area. Heating the area improves the plasticity and deformation resistance of the aluminum material in the bending region, reducing the stress on the copper-aluminum bonding layer during bending. This solves the problem of aluminum tearing or bonding layer cracking during the bending process of copper-aluminum composite sheets caused by an insufficient bending radius. Simultaneously, the precise heating of the designated area of ​​the strip avoids excessive temperature rise in the continuous stamping die, preventing the continuous stamping die from malfunctioning due to excessive temperature affecting the clearance between the cutting edges of the upper and lower dies. The implementation of this continuous stamping die and production method overcomes the limitations of customer product structures, effectively improving the local forming performance of copper-aluminum composite sheets during stamping without modifying the product structure, thus increasing product yield. Attached Figure Description

[0017] Figure 1 A schematic diagram of the mold opening state during the production process of laser-heated continuous stamping dies; Figure 2 A schematic diagram of the closed mold state during the production process of laser-heated continuous stamping dies; Figure 3 For the appendix Figure 2 Enlarged schematic diagram of part A in the middle; Figure 4 For the appendix Figure 2 Enlarged schematic diagram of part B in the middle; Figure 5 This is a schematic diagram of the appearance of the copper-aluminum composite connecting piece in the embodiment; Figure 6 This is a schematic diagram of the material strip's appearance in the embodiment; Figure 7 This is a top view of the lower die without the strip in place; Figure 8 This is a top view of the lower die in the strip placement position; Figure 9 For the appendix Figure 8 Enlarged schematic diagram of a portion of the central area (D); Figure 10 This is a schematic diagram of the appearance of the laser adjustment plate; Figure 11 Front view of a laser-heated continuous stamping die; Figure 12 Laser-heated continuous stamping die along the attached Figure 8 Schematic diagram of the cross-section structure in the CC direction; Figure 13 This is a schematic diagram of the exterior of the reflector assembly; Figure 14 This is a schematic diagram of the exploded view of the mirror assembly structure; Figure 15 A schematic diagram showing the appearance of the lower mold with the laser adjustment plate in place; Figure 16 A schematic diagram illustrating the principle of laser focus adjustment for laser-heated continuous stamping dies.

[0018] In the diagram: 1. Upper die; 1.7. Micro switch pressure block; 2. Lower die; 2.1. Lower template; 2.2. Lower die holder; 2.3. Lower die pad; 2.4. Lower die fixing plate; 2.5. Optical path hole; 2.6. Reflector assembly; 2.6.1. Reflector bracket; 2.6.1.1. Lens placement slot; 2.6.2. Reflecting lens; 2.6.3. Lens pressure plate; 2.7. Micro switch; 3. Laser heater; 3.1. Laser head; 3.2. Laser pointer; 4. Punch press slide; 5. Punch press worktable; 6. Strip material; 6.1. Punching hole Workstations; 6.2 Trimming and Embossing Workstation; 6.3 Blanking Workstation A; 6.4 Blanking Workstation B; 6.5 Heating Workstation; 6.5.1 Heating Zone of Material Strip; 6.6 Bending Workstation A; 6.7 Bending Workstation B; 6.8 Blanking and Separation Workstation; 8. Connecting Piece; 8.1 Connecting Piece Body; 8.2 Connecting Leg A; 8.2.1 Bending Zone A; 8.3 Connecting Leg B; 8.3.1 Bending Zone B; 8.4 T-Slot Head; 9. Laser Adjustment Plate; 9.1 Focusing / Alignment Baseline; 9.2 Heating Zone Adjustment Marking. Detailed Implementation

[0019] The present invention will be explained in detail through the following embodiments. The purpose of disclosing the present invention is to protect all technical improvements within the scope of the present invention.

[0020] A laser-heated continuous stamping die is used for stamping copper-aluminum composite sheets to solve the problems of surface tearing of aluminum or cracking of the copper-aluminum bonding layer when bending with small radius angles; see the attached instruction manual. Figure 1 , 2The laser-heated continuous stamping die includes an upper die 1, a lower die 2, and a laser heater 3. A reflector assembly 2.6 is fixedly mounted on the lower part of the lower die 2. During operation, the upper die 1 is fixed to the lower end of the punch slide 4 of the stamping machine via a die fixing plate, and the lower die 2 is fixed to the upper end of the punch worktable 5 of the stamping machine via the die fixing plate. The laser heater 3 is separate from the upper die 1 and lower die 2, and is fixedly mounted in front of them. In its initial state, the emitted laser is perpendicular to the front face of the punch worktable 5 to mitigate the impact of production vibrations on the galvanometer in the laser heater 3. During operation, the strip 6 is horizontally positioned between the upper die 1 and lower die 2. More precisely, it is set on the lower die 2. The upper die 1 opens and closes vertically relative to the lower die 2. The strip 6 moves forward synchronously along the process setting direction with a set step distance as the upper die 1 and lower die 2 open and close, and enters the next station in sequence for stamping processing at each station. As the upper die 1 and lower die 2 open and close, the laser heater 3 intermittently emits green laser light, which is reflected by the reflector assembly 2.6 onto the set area of ​​the strip 6 for heating. This improves the plasticity and deformation resistance of the aluminum material in the bending area, reduces the stress on the copper-aluminum bonding layer during the bending process, and thus solves the problem of aluminum material tearing or bonding layer cracking during the bending process of copper-aluminum composite plates caused by the small bending R angle during the stamping production process.

[0021] See the instruction manual appendix Figure 3 The laser-heated continuous stamping die is equipped with a signal triggering device, which includes a microswitch block 1.7 fixedly mounted on the upper die 1 and a microswitch 2.7 fixedly mounted on the lower die 2. The positions of the microswitch block 1.7 and the microswitch 2.7 correspond. During the closing process of the upper die 1 and the lower die 2, the microswitch block 1.7 triggers the microswitch 2.7 to operate. The microswitch 2.7 is electrically connected to the laser heater 3, controlling the laser heater 3 to synchronously operate the opening and closing movement between the upper die 1 and the lower die 2. It should be noted that the laser heating of the strip 6 does not occur at the instant when the upper and lower dies are completely closed during stamping. Instead, it utilizes the rhythm of the die opening and closing movement to trigger the microswitch 2.7 to send a signal to trigger the laser heater 3 to operate. A delay can be set between the microswitch 2.7 sending the signal and the laser heater 3 operating (the delay time is controlled by the controller of the laser heater 3). After the upper die 1 and lower die 2 open, the strip 6 moves forward at a set step distance to the next station and stops. At this time, the micro switch 2.7 sends a signal, and after a delay, triggers the laser heater 3 to work, heating the strip area at heating station 6.5. After heating is completed, the upper die 1 and lower die 2 close and stamp. See the attached instruction manual. Figure 7 , Figure 12The lower die 2 has a light path hole 2.5 that runs through the lower die plate 2.1 and the lower die frame 2.2. This light path hole forms an unobstructed light path channel from the upper surface of the lower die to the reflector assembly 2.6 at the heating station 6.5. When the strip 6 is positioned at the heating station 6.5, its bending area to be heated is directly above the light path hole 2.5. The laser beam is reflected from bottom to top by the reflector assembly 2.6 and passes through the light path hole 2.5 to directly irradiate the lower surface of the strip 6. There are no mold components blocking the light path, ensuring direct and efficient heating.

[0022] See the instruction manual appendix Figure 4 , 12 Section 16 further explains the composition and optical path system of the laser heater 3. The laser heater 3 is equipped with a laser head 3.1 whose position and angle can be adjusted. A field lens is installed in the laser head 3.1, with a focal length of F400mm and a designed working distance of approximately 372mm. This long focal length configuration allows for a distance of approximately 370mm between the light outlet of the laser head 3.1 and the working plane of the lower mold 2, providing ample space for mold opening and closing and production auxiliary devices, and ensuring sufficient distance between the laser head 3.1 and the continuous stamping die to accommodate peripheral equipment such as the feeder. Laser head 3.1 emits a red laser pointer beam coaxial with the working green laser, in a dot-shaped pattern. A laser pointer 3.2 is fixedly mounted on laser head 3.1, emitting a linear, red pointer beam. An angle is formed between the axis of laser pointer 3.2 and the axis of the field lens. This angle is determined based on the focal length of the field lens fixed on laser head 3.1 and is related to the focal distance of the green laser emitted from laser head 3.1. With the field lens focal length selected as F400mm, the focused spot diameter on the working focal plane is approximately 0.6mm, which is the minimum spot size and corresponds to the highest energy density. Further explanation regarding laser heater 3: Laser heater 3 is a dedicated laser heating device based on the control card of a laser rust removal machine. The laser uses a 3000W green laser with a wavelength of 532nm, specifically designed for heating aluminum or copper materials. Compared to infrared lasers, copper-aluminum composite plates have a higher absorption rate for 532nm green lasers. The absorption rate of copper for this wavelength is approximately 40%, and for aluminum, it is approximately 12%, both higher than the absorption rate for 1064nm infrared lasers, which is beneficial for achieving rapid and localized heating. The laser head 3.1 is equipped with an X-axis and Y-axis dual galvanometer system. The galvanometers are high-power laser-specific metal galvanometers, whose maximum scanning range can cover a heating area of ​​60mm×60mm at a focal length of F400mm. The Z-axis, i.e., the laser emission direction, is achieved through a mechanical adjustment device, and is locked after adjustment.

[0023] See the instruction manual appendix Figure 5 In a specific embodiment of the present invention, the appendix is ​​used. Figure 5Taking the connecting piece 8 as an example, the structural features, adjustment, and production methods of the laser-heated continuous stamping die are specifically explained. The connecting piece 8 is made of copper-aluminum composite plate, and its structure includes a connecting piece body 8.1, connecting feet A8.2, connecting feet B8.3, and a T-slot head 8.4. Connecting feet A8.2 and B8.3 are respectively located on the left and right sides of the connecting piece body 8.1. A bending area A8.2.1 is provided between connecting foot A8.2 and the connecting piece body 8.1, and a bending area B8.3.1 is provided between connecting foot B8.3 and the connecting piece body 8.1. The radius of curvature of bending area A8.2.1 is only 1.0 mm, which is much smaller than the radius of curvature of bending area B8.3.1 of 2.5 mm. Two connecting pieces 8 are symmetrically arranged during stamping production. In this embodiment, the total thickness of the copper-aluminum composite plate is 3.0 mm, of which the copper layer thickness is 1.5 mm and the aluminum layer thickness is 1.5 mm. During the production of this connecting piece 8, due to the fact that the radius of the bend A8.2.1 is only 1.0mm and the total thickness of the sheet material is 3.0mm, the tensile strain of the outer aluminum material during bending is extremely large, far exceeding the elongation limit of aluminum material at room temperature. This causes frequent tearing on the outer surface of the aluminum layer on the outside of the bend A8.2.1, and the copper-aluminum interface cracks due to the huge shear stress, resulting in the product's production yield consistently failing to exceed 60%.

[0024] See the instruction manual appendix Figure 6 The diagram shows the process layout for the stamping production of connecting piece 8. The process layout for connecting piece 8 includes eight stations, in the following order: punching station 6.1, trimming and embossing station 6.2, blanking station A 6.3, blanking station B 6.4, heating station 6.5, bending station A 6.6, bending station B 6.7, and blanking and separation station 6.8. That is, the strip 6 passes through eight stamping stations in the laser-heated continuous stamping die to finally produce connecting piece 8. Compared with the traditional process layout diagram, this process layout diagram for the stamping production of connecting piece 8 has an additional heating station 6.5. In other words, the heating station 6.5 does not actually exist in the traditional process layout diagram for connecting piece 8.

[0025] See the instruction manual appendix Figure 11 , 12The diagram shows the structure of the lower die 2, which includes a lower template 2.1, a lower die frame 2.2, a lower die pad 2.3, a lower die fixing plate 2.4, and a reflector assembly 2.6. The lower template 2.1 and the lower die frame 2.2 are provided with a light path hole 2.5. The reflector assembly 2.6 is fixedly installed at the lower part of the lower die frame 2.2, corresponding to the light path hole 2.5. It should be noted that different manufacturers may have structural differences in the design of stamping dies for the same product. For example, the lower die structure may also include components such as a lower die pad, inserts, and inserts. However, for laser-heated continuous stamping dies, the light path hole 2.5 must penetrate through the above-mentioned components of the lower die. The light path hole 2.5 must be clearly visible in the top view of the lower die 2, meaning that the laser reflected by the reflector assembly 2.6 can directly irradiate the strip 6 located on the upper surface of the lower die 2.

[0026] See the instruction manual appendix Figure 7 , 8 9, Appendix Figure 7 The image shows a top view of the lower die 2, in which the optical path hole 2.5 can be seen. The optical path hole 2.5 has a stepped surface on the upper end face of the lower die 2. This stepped surface is precision-machined and is at the same plane height as the upper surface of the lower die 2 where the material strip 6 is placed, ensuring the accuracy of subsequent focus positioning. (Attached image) Figure 8 This is also a top view of the lower die 2, showing the material strip 6. It can be seen that the optical path hole 2.5 is directly opposite the heating station 6.5 in the stamping production process layout diagram of the connecting piece 8; (Attached) Figure 9 The image shows the laser-irradiated heating zone 6.5.1 of the strip. This heating zone is rectangular, 15mm long and 3mm wide, and completely covers the unfolded area of ​​the bending zone A8.2.1 on the strip.

[0027] See the instruction manual appendix Figure 10 The appearance of the laser adjustment plate 9 is shown. When the continuous stamping die is fixedly set on the stamping machine, the laser adjustment plate 9 is used to adjust the distance between the laser head 3.1 and the continuous stamping die, as well as the position of the laser irradiation on the strip 6. The laser adjustment plate 9 is made of frosted glass plate and semi-transparent plastic plate. The plate surface is provided with a focusing / alignment reference line 9.1 and a heating area adjustment mark 9.2. The size and shape of the heating area adjustment mark 9.2 are completely consistent with the heating area 6.5.1 of the strip, which is a rectangular frame of 15mm×3mm.

[0028] See the instruction manual appendix Figure 13 , 14The reflector assembly 2.6 includes a reflector bracket 2.6.1, a reflector lens 2.6.2, and a lens clamping plate 2.6.3. The reflector bracket 2.6.1 is equipped with a lens placement slot 2.6.1.1 and a water-cooling channel. The water-cooling channel is connected to cooling water, and the cooling water flow rate is set to 2L / min to effectively reduce the overall temperature of the reflector assembly 2.6 and prevent thermal deformation of the lens due to absorption of some laser energy. The reflector lens 2.6.2 is placed in the lens placement slot 2.6.1.1 and fixed by the lens clamping plate 2.6.3. The reflector lens 2.6.2 is made of a high-power laser-specific metal reflector with a reflectivity of more than 98% for 532nm green laser light, ensuring efficient transmission of laser energy.

[0029] A method for adjusting a laser-heated continuous stamping die specifically includes the following steps: S1. Installation of mold and laser heater 3: The upper mold 1 is fixedly installed at the lower part of the punch press slide 4 by a pressure plate; the lower mold 2 is fixedly installed at the upper part of the punch press worktable 5 by a pressure plate; the laser heater 3 is fixedly installed at the front of the punch press; the red laser indicator light emitted by the laser head 3.1 is perpendicular to the punch press worktable 5 in the initial state.

[0030] S2. Adjustment of the initial position and working focus of laser heater 3: See the instruction manual appendix. Figure 15 , 16 Start the stamping machine and open the upper and lower dies to their maximum stroke. Place the laser adjustment plate 9 stably on the stepped surface of the upper end face of the optical path hole 2.5 of the lower die 2. First, perform optical axis alignment: by adjusting the horizontal and vertical adjustment screws on the mounting bracket of the laser head 3.1, make the coaxial red laser indicator light spot coincide with the origin of the focusing / alignment reference line 9.1 of the laser adjustment plate 9. At this time, the laser beam is aligned with the center of the optical path hole 2.5, completing the initial position adjustment of the laser head 3.1. Secondly, focus adjustment is performed: the angle between the axis of the laser pointer 3.2 and the optical axis of the field lens has been precisely set and locked according to the F400mm focal length. The principle of this angle setting is as follows: when the distance between the heating plane of the material strip 6 and the laser head 3.1 is exactly equal to the designed working distance of the field lens 372mm, the linear red light emitted by the laser pointer 3.2 will precisely pass through the horizontal reference line on the laser adjustment plate 9. Therefore, the operator adjusts the front and rear positions of the overall mounting base of the laser head 3.1 until the linear laser emitted by the laser pointer 3.2 is completely aligned with the horizontal line of the focusing / alignment reference line 9.1 of the laser adjustment plate 9, thus completing the precise adjustment of the focal length. At this time, the focal point of the laser falls exactly on the lower surface of the material strip 6, the heating spot size reaches the designed 0.6mm, and the energy density is approximately 1.06×10⁻⁶. 4 W / mm². For the laser focus adjustment principle, please refer to the instruction manual. Figure 16After the focal length of the field lens of laser head 3.1 is selected, the working focus position of the laser emitted from laser head 3.1 is also determined. By adjusting the angle between the axis of laser indicator 3.2 and the axis of the field lens, the red laser indicator spot emitted by laser head 3.1 and the red laser indicator line emitted by laser indicator 3.2 are made to coincide at the working focus position of the laser emitted from laser head 3.1. Then, the angle between the axis of laser indicator 3.2 and the axis of the field lens is locked. When adjusting the focal length of laser heater 3, when the red laser indicator spot emitted by laser head 3.1 and the linear laser emitted by laser indicator 3.2 both coincide with the horizontal line of the focusing / alignment reference line 9.1 of laser adjustment plate 9, it indicates that the adjustment of the working focus of laser heater 3 is complete. It is particularly important to note that the green laser output must be turned off when adjusting the initial position and working focus of laser heater 3 to ensure the safety of the operators during the adjustment process.

[0031] To balance heating efficiency and temperature uniformity, this invention allows for flexible adjustment of the spot size irradiated onto the material strip. In this embodiment, the heating zone size is 15mm × 3mm. Considering the need for higher power density to ensure the temperature rise rate after the heating time is shortened to 400ms, an excessively large defocused spot is not advisable. After achieving precise focusing, the laser head is moved forward 5mm using the Z-axis mechanical adjustment device of the laser head 3.1, so that the plane of the material strip 6 is in a slightly defocused state (at this time, the focal point is located inside the material strip). Testing showed that under the condition of 5mm defocus, the diameter of the spot irradiated onto the material strip increased from 0.6mm to approximately 1.2mm, with an energy density of approximately 2.65 × 10³ W / mm². Using a 1.2mm spot size and a 1.0mm scanning line spacing for reciprocating filling, the high power density and dense scanning line spacing ensure that sufficient heat is input to the 3.0mm thick copper-aluminum composite plate to reach 180℃ within a short time of 400ms, while also forming a uniform energy distribution within a 15mm × 3mm rectangular area. After the Z-axis adjustment is completed, lock the mechanical adjustment device.

[0032] S3. Adjusting the heating position and shape of the heating area of ​​the laser on the material strip 6: In the laser heater 3, the heating area of ​​the material strip 6 is set by aligning the scanning range of the red laser indicator light emitted by the laser head 3.1 with the heating area adjustment mark 9.2 on the laser adjustment plate 9. Specifically, the laser uniquely and accurately corresponds to the shape of the bending area of ​​the part, which is achieved by the X-axis and Y-axis dual galvanometers in the laser head 3.1. After completing the initial alignment, the product heating shape programming mode is entered. In this embodiment, the heating area 6.5.1 corresponding to the bending area A8.2.1 is a rectangular area, 15mm long and 3mm wide. The operator sets the filling scanning parameters in the laser heater's operating software as follows: scanning area size 15mm×3mm, scanning speed increased to 5000mm / s to adapt to the shortened heating cycle of 400ms and ensure multiple scanning coverage, filling line spacing 1.0mm, and a "bow" shaped reciprocating scanning path. The laser focus will fill and scan at high speed along the above trajectory based on a 1.2mm spot size. Within a 400ms heating time, the rectangular region was uniformly scanned multiple times, thus establishing a uniform high-temperature field throughout the bending area, with energy strictly confined within this rectangle. (From the attached...) Figure 8 and 9 As can be seen, the heating zone 6.5.1 of the strip is directly aligned with the bending line of the subsequent bending process, achieving a "unique correspondence" of laser energy in space. This scanning heating method dynamically generates the heating shape rather than using a fixed beam, thus achieving precise heating of the designated area of ​​the strip 6. This heating method avoids the problem of excessive temperature rise in the continuous stamping die caused by an excessively large heating range or excessive energy in the strip 6. It also prevents the continuous stamping die from malfunctioning due to excessive temperature rise affecting the fit clearance between the cutting edges of the upper and lower dies at the punching station 6.1, trimming and embossing station 6.2, blanking station A6.3, and blanking station B6.4.

[0033] S4. Set the operating parameters of laser heater 3 to complete the adjustments before the production of continuous stamping die for copper-aluminum composite materials using laser heating. The operating parameters of laser heater 3 include output power, heating time, and start-up delay time. In the control system of laser heater 3, the operator can set heating parameters that are completely synchronized with the production cycle to accurately control the total energy input to the material strip, thereby accurately reaching the target temperature. Specifically: the output power is adjustable from 10% to 100% of the rated power, i.e., 300W to 3000W; the heating time is a controllable laser pulse width. Based on the stamping cycle of the stamping machine tool of 35 times per minute, each heating cycle has a period of about 1.7 seconds, of which the static window after the material strip is fed in and stops is about 0.9 seconds. The 400ms heating time is entirely within this window; the start-up delay is set to 80 milliseconds after the microswitch 2.7 trigger signal to ensure that the material strip 6 stops completely at the heating station and eliminates vibration before starting heating, ensuring the accuracy of the heating position.

[0034] In this embodiment, the copper-aluminum composite plate has a total thickness of 3.0 mm, with a copper layer thickness of 1.5 mm and an aluminum layer thickness of 1.5 mm. This plate has a large overall heat capacity, and the high thermal conductivity of the copper layer rapidly conducts heat to the surrounding environment. When the heating time is set to 400 ms, a large amount of total energy needs to be input in a short time to achieve the target temperature of 180°C. Therefore, it is necessary to increase the laser output power to increase the heating rate and simultaneously reduce the defocusing amount to increase the energy density. Through systematic process testing, using an infrared thermometer to monitor the temperature of the heating zone 6.5.1 of the material strip in real time, the optimal parameter combination was determined to be: laser output power set to 2800-3000 W, heating time set to 400 ms, and start-up delay set to 80 ms. Under the above parameters, using a 1.2mm spot size with 5mm defocus, a scanning speed of 5000mm / s, and a filler line spacing of 1.0mm, a 15mm×3mm rectangular area was scanned and heated. After 400ms of laser irradiation, the temperature of the bending area uniformly rose from room temperature to 180℃, with the temperature deviation controlled within ±10℃, precisely falling within the optimal plasticity improvement range of 150-200℃. When the material strip 6 ran at a cycle of 35 times per minute, the temperature consistency of each heating station was good, with batch fluctuations less than ±8℃. The shortened heating time to 400ms improved the compatibility of the production cycle and reserved space for future increases in stamping speed. If a composite sheet with a different total thickness or copper-aluminum ratio is used, only the power and heating time need to be adjusted according to the thermophysical parameters of the material. For example, when the total thickness is reduced to 2.0mm, the power can be reduced to 2100W or the heating time can be shortened to 300ms to achieve the same target temperature of 180℃. The combination and adjustment of parameters provide those skilled in the art with clear and quantifiable temperature control methods. Once the above parameters such as power, time, and scanning are set, the adjustments before production of the laser-heated continuous stamping die are complete, and it can be put into continuous production.

[0035] A method for producing a continuous stamping die using laser heating involves adding a heating station 6.5 before the bending station A6.6 when producing a connecting piece 8 of copper-aluminum composite material using a continuous stamping die. The heating zone 6.5.1 of the strip 6 is heated to 180°C using a laser. At this temperature, the elongation of the aluminum increases from approximately 12% at room temperature to approximately 35%, the deformation resistance decreases by approximately 40%, and the diffusion bonding strength at the copper-aluminum interface is enhanced due to the increased temperature. In the above embodiment, with a power of 3000W, a heating time of 400 milliseconds, and a scanning spot of 1.2mm, the bending area is uniformly heated to 180°C. During bending at the subsequent bending station A6.6, the plasticity of the aluminum is significantly improved, the deformation resistance is significantly reduced, and the bonding strength at the copper-aluminum interface is sufficient to withstand the shear stress generated by bending. Through continuous production verification, the problems of aluminum material tearing and bonding layer cracking in the 8-bending area A8.2.1 of the connecting piece have been completely solved. The product yield has been greatly improved from less than 60% before the improvement to more than 97%. At the same time, no modifications were required to the R-corner structure of the customer's product, and the original design dimensions and installation fit of the product were completely maintained.

[0036] It should be understood that this solution is not limited to the specific embodiments described above. Devices and structures not described in detail herein should be understood as being implemented in a manner common to the art. Any person skilled in the art can make many possible variations and modifications to this solution, or modify it into equivalent embodiments, without departing from the scope of this solution, using the methods and techniques disclosed above. This does not affect the substantive content of this solution. Therefore, any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of this solution, without departing from its scope, still fall within the protection scope of this solution.

[0037] The parts of this invention not described in detail are prior art.

Claims

1. A laser-heated continuous stamping die, comprising an upper die (1) and a lower die (2), wherein the upper die (1) and the lower die (2) perform relative opening and closing movements; characterized in that: It also includes a laser heater (3) that is separated from the upper mold (1) and the lower mold (2), and a reflector assembly (2.6) set on the lower mold (2). The laser heater (3) is equipped with an X-axis and Y-axis dual galvanometer system. The separation design of the laser heater (3) from the upper mold (1) and the lower mold (2) is used to solve the influence of production vibration on the galvanometer in the laser heater (3). When the continuous stamping die is working, the strip (6) is set between the upper mold (1) and the lower mold (2). The relative opening and closing between the upper mold (1) and the lower mold (2) moves forward with a set step distance and enters the next station in sequence. The laser heater (3) emits laser light, which is reflected by the reflector assembly (2.6) in the set area of ​​the strip (6) for local heating. A signal triggering device is provided on the continuous stamping die, and the signal triggering device is electrically connected to the laser heater (3); The lower mold (2) includes a lower template (2.1) and a lower mold frame (2.2). The lower template (2.1) and the lower mold frame (2.2) are provided with light path holes (2.5). The reflector assembly (2.6) corresponds to the light path holes (2.5) and is fixedly installed at the lower part of the lower mold frame (2.2). The laser heater (3) includes a laser head (3.1), a field lens is provided on the laser head (3.1), and a red laser indicator light is provided in the laser head (3.1) coaxial with the laser emission direction; a linear, red laser indicator (3.2) is provided on the laser head (3.1); an angle is provided between the axis of the laser indicator (3.2) and the axis of the field lens; The continuous stamping die also includes a laser adjustment plate (9) for optical path adjustment and alignment; when the continuous stamping die is fixedly installed on the stamping machine, the laser adjustment plate (9) is used to adjust the distance between the laser head (3.1) and the continuous stamping die, as well as the position of the laser irradiation on the strip (6); the laser adjustment plate (9) is a frosted glass plate or a transparent plastic plate; the laser adjustment plate (9) is provided with a focus / alignment reference line (9.1) and a heating area adjustment mark (9.2).

2. The laser-heated continuous stamping die according to claim 1, characterized in that: A water-cooling channel is provided in the reflector assembly (2.6).

3. The laser-heated continuous stamping die according to claim 1, characterized in that: The working laser of the laser heater (3) is a green laser with a wavelength of 532nm.

4. The laser-heated continuous stamping die according to claim 1, characterized in that: The output power of the laser heater (3) is 2500W-3000W.

5. A method for adjusting a laser-heated continuous stamping die according to any one of claims 1-4, characterized in that: Specifically, the following procedures are included: S1. Installation of mold and laser heater (3): The upper mold (1) is fixedly installed on the lower part of the punch press slide (4) by a pressure plate; the lower mold (2) is fixedly installed on the upper part of the punch press worktable (5) by a pressure plate; the laser heater (3) is fixedly installed on the front of the punch press; the red laser indicator light emitted by the laser head (3.1) is perpendicular to the punch press worktable (5) in the initial state; S2. Adjustment of the initial position of the laser heater (3): Start the stamping machine, open the upper and lower dies, and place the laser adjustment plate (9) on the upper end face of the optical path hole (2.5) of the lower die (2); first, adjust the horizontal and vertical position of the laser head (3.1) so that the red laser indicator light spot coincides with the origin of the focusing / alignment reference line (9.1) of the laser adjustment plate (9); adjust the distance between the laser head (3.1) and the lower die (2) so that the linear laser emitted by the laser indicator (3.2) coincides with the horizontal line of the focusing / alignment reference line (9.1) of the laser adjustment plate (9); S3. Adjust the heating position of the laser on the material strip (6): In the laser heater (3), the scanning range of the red laser indicator light emitted by the laser head (3.1) is set to coincide with the heating area adjustment mark (9.2) of the laser adjustment plate (9); S4. Set the working parameters of the laser heater (3) and complete the adjustment before the production of the continuous stamping die for the copper-aluminum composite material laser heating. The working parameters of the laser heater (3) include output power, heating time and start-up delay time.

6. A method for producing a laser-heated continuous stamping die according to any one of claims 1-4, characterized in that: When using a progressive die to produce copper-aluminum composite parts, a heating station is added before the bending station. At the heating station, the bending area is locally heated to 150℃-200℃ using a laser, which improves the plasticity of the aluminum in the bending area and reduces the deformation resistance; at the same time, it avoids excessive temperature rise of the progressive die as a whole.

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