Knife-shear integrated laser processing system and method

Abstract

The invention discloses a knife-shear integrated laser processing system and method, and belongs to the field of laser processing, and the knife-shear integrated laser processing system comprises a control unit which is used for controlling and executing the coordination of cleaning, welding, hardening and cutting procedures through a program, and automatically adjusting processing parameters according to sensing feedback; the laser output mechanism is used for generating a laser beam according to an instruction of the control unit and rapidly deflecting and accurately positioning the laser beam through a laser scanning galvanometer so as to complete machining of each working procedure; the information sensing mechanism is used for collecting a plasma spectrum and a laser penetration image in the machining process and feeding back a spectrum signal and a penetration state to the control unit; and the auxiliary mechanism is used for clamping the workpiece and providing inert protective gas and compressed air.

Description

Technical Field

[0001] This invention belongs to the field of laser processing technology, and particularly relates to an integrated laser processing system and method for cutting and scissing. Background Technology

[0002] As the manufacturing industry upgrades towards high efficiency, precision, and green practices, traditional processes such as arc welding and resistance welding are increasingly revealing drawbacks in high-end sheet metal processing, including high heat input, difficulty in controlling deformation, and long post-weld processing chains. Especially in applications such as automotive lightweighting, power battery casings, and aerospace thin-walled structures, the requirements for weld quality, dimensional accuracy, and subsequent surface treatment are extremely high. The conventional multi-equipment, multi-process model of "cleaning first, then welding, then straightening, and finally machining / grinding" is no longer sufficient to balance cycle time and yield. Patent document CN113560727A proposes achieving cleaning / welding / cutting functions within a single handheld head by adjusting power density. However, this solution is limited to close-range manual operation and is unsuitable for automated intelligent production lines, and it does not mention a hardening step. Patent document CN112846552A proposes a laser cutting and welding integrated scissor manufacturing equipment. This patent presents an integrated device, which is essentially a production line. To accommodate welding and cutting, welding and cutting heads are installed, complicating the equipment.

[0003] Because galvanometer scanning laser systems deflect the laser beam using two- or three-axis high-speed mirrors, they can achieve precise filling of complex trajectories in milliseconds, providing a hardware foundation for integrated welding and surface treatment. Public literature has reported the use of galvanometer lasers in oscillating welding: expanding weld width, stabilizing pinholes, reducing porosity and cracks through circular, spiral, or figure-eight scanning paths, significantly improving the adaptability of butt joint gaps. Regarding laser hardening of workpieces, patent document CN101109034A discloses a laser hardening technology for improving the surface hardness of railway components. This technology uses a CO2 laser and a broadband integrating mirror to convert the circular laser spot into a rectangular spot. The converted spot is used to scan the metal surface, causing rapid heating and cooling to form a surface hardened layer. This technology requires a broadband integrating lens, has a relatively shallow processing depth, and requires the application of a light-absorbing material to the processed surface. Patent document CN105177274 discloses a laser hardening process that uses a YAG laser and increases the spot diameter by increasing the defocusing amount. The maximum hardening depth reached is 1.1 mm. Although this method increases the processing area by changing the defocusing amount, it cannot increase the processing area indefinitely. This method can only be applied to small-sized workpieces and has a shallow hardening depth, making it unsuitable for workpieces with slightly larger thicknesses.

[0004] To address the challenges of thin sheet metal cutting tools, high hardness requirements, and sensitive cutting edge precision, a streamlined process of cleaning, welding, hardening, and cutting was designed to reduce heat accumulation and deformation in thin sheets. Furthermore, an integrated laser processing system and method for cutting tools is proposed. This system reduces the number of devices and workpiece handling, while ensuring weld performance and dimensional accuracy through closed-loop parameter control, meeting a pressing need in the high-end sheet metal processing field. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention proposes an integrated laser processing system and method for cutting and scissors, thereby resolving the issues present in the prior art.

[0006] To achieve the above objectives, the present invention provides an integrated laser processing system and method for knives and scissors, comprising: The control unit is used to coordinate the cleaning, welding, hardening and cutting processes through program control, and automatically adjust the processing parameters based on sensor feedback; The laser output mechanism is used to generate a laser beam according to the instructions of the control unit, and to quickly deflect and precisely position the laser beam through a laser scanning galvanometer to complete each processing step. The information sensing mechanism is used to collect plasma spectra and laser melting images during the processing, and to feed back the spectral signals and melting status to the control unit. Auxiliary mechanism for clamping workpieces and providing inert protective gas and compressed air.

[0007] Optionally, the control unit includes: The cleaning control module is used to automatically calculate and adjust the laser cleaning power based on the comparison results between the characteristic spectral information collected by laser-induced breakdown spectroscopy and the spectral characteristics of the matrix. The welding control module is used to automatically calculate and adjust the laser welding power based on the comparison between the penetration state and the moderate penetration state identified by the pinhole image. The hardening control module is used to automatically calculate and adjust the laser defocusing amount based on the comparison between the penetration state and the just-penetrated state identified by the pinhole image. The laser power used for hardening is the same as the welding power. The cutting control module is used to automatically calculate and adjust the laser cutting power based on the comparison between the penetration state and the over-penetration state identified by the pinhole image.

[0008] Optionally, the laser output mechanism includes: Laser, used to generate laser light; Optical fiber is used to transmit laser light generated by a laser. A laser scanning galvanometer, connected to an optical fiber, is used to receive the laser beam and achieve rapid deflection and precise positioning of the laser beam; A coaxial dichroic mirror, mounted on a laser scanning galvanometer, is used to collect plasma spectra and laser penetration images generated during the processing.

[0009] Optionally, the focal length of the focusing lens of the laser scanning galvanometer is greater than 300 mm.

[0010] Optionally, the auxiliary mechanism includes: The motion mechanism is used to carry and move the workpiece to the laser processing area; Gas-assisted mechanism, including a gas source that provides inert protective gas and a gas source that provides compressed air; A solenoid valve, located at the gas source outlet, is used to control the switching of gas passages. A pressure sensor is installed at the gas source outlet to monitor gas pressure.

[0011] Optionally, both the solenoid valve and the pressure sensor are connected to the control unit, which controls the gas switching according to the process switching command.

[0012] Optionally, the cleaning and hardening processes performed by the laser output mechanism adopt pulsed laser mode, while the welding and cutting processes adopt continuous laser mode.

[0013] Optionally, the welding and hardening processes performed by the laser output mechanism are processed by laser oscillating scanning with a spiral trajectory; The oscillation amplitude of the spiral trajectory is 0.5 mm to 2 mm.

[0014] This invention also provides a method for an integrated laser processing system for knives and scissors, comprising the following steps: A laser processing system integrating knives and scissors is provided, the system comprising a control unit, a laser output mechanism, an information sensing mechanism, and an auxiliary mechanism; The workpiece to be processed is fixed on the fixture of the auxiliary mechanism; The laser output mechanism, in accordance with the instructions of the control unit, uses a laser beam to perform laser cleaning on the surface of the workpiece. In an inert protective gas environment, the laser output mechanism is used to perform laser welding on the cleaned workpiece area by laser oscillation scanning; The laser output mechanism employs laser oscillating scanning to perform laser remelting and hardening on specific areas of the workpiece. With the assistance of compressed air, the laser output mechanism uses a laser beam to perform laser cutting on the workpiece along a predetermined path; The laser cleaning, laser welding, laser remelting and hardening, and laser cutting processes are automatically adjusted by the control unit based on the spectral signals and melting state images fed back by the information sensing mechanism.

[0015] Optionally, the expression for automatically adjusting the laser processing parameters of each process is: ; ; ; ; in, f For frequency, v For scanning speed, A For the amplitude of the oscillation, d The spacing between the spirals, t For time, x 0 、y 0 The coordinates of the origin are... r 0 Let be the radius of the light spot, x be the position variable in the x-direction, and y be the position variable in the y-direction. For the energy utilization rate of laser, The dynamic x-position function of the laser varies with time. Let y be the time-varying dynamic position function of the laser. Let T be the total energy input at the spatial point (x, y), and T be the upper limit of the time for energy integration.

[0016] Compared with the prior art, the present invention has the following advantages and technical effects: This invention integrates the cleaning, welding, hardening, and cutting processes of scissors using a single laser galvanometer system, completing all processing in a single clamping operation. This solves the problems of low efficiency and multiple clamping errors caused by traditional multi-device, multi-process workflows. The system uses closed-loop feedback to adjust laser parameters in real time, ensuring weld penetration quality, hardened layer uniformity, and cutting accuracy, significantly improving processing consistency and product yield. Simultaneously, inter-process collaboration and waste heat utilization reduce heat input and deformation, making it particularly suitable for high-precision, high-performance processing of dissimilar thin steel plates. This significantly shortens the production cycle and reduces overall costs while improving the hardness and durability of scissors products.

[0017] This invention achieves rapid deflection and precise positioning of the laser beam by using a large focal length scanning galvanometer, allowing the machine to remain stationary, reducing mechanical response time, and improving welding accuracy. Furthermore, by incorporating a coaxial dichroic mirror within the galvanometer to collect plasma spectra, the laser penetration image is processed by the system for spectral signal analysis and keyhole penetration status analysis.

[0018] Unlike assembly line processing, the processing in this invention is completed by a single machine. This machine not only intelligently controls its parameters but also utilizes the residual heat from the previous process through short-time process transitions to achieve synergistic effects. The processes are not simply sequentially superimposed but rather complementary and optimized. In this invention, the spiral scanning path of the cleaning process not only removes the oxide layer but also provides a uniform heat input foundation for the welding process; the oscillating laser in the welding process not only controls the penetration depth but also improves welding quality through stirring; the defocusing control in the hardening process not only increases hardness but also enhances the impact resistance and durability of the tool, providing a stable cutting edge structure for the cutting process. The advantages of this method also lie in the fact that, to better adapt to the performance requirements of the blades and scissors, dissimilar steels are used. These dissimilar steels are two steels with different physical properties selected based on the requirements of the blade body and the cutting edge. The blade body is made of conventional 304 stainless steel, which offers excellent overall performance in terms of corrosion resistance, high toughness, good weldability, and low cost. The cutting edge is made of special steel with high hardness, such as M390 powder steel, etc. The laser remelting hardening process is applied to the cutting edge. Attached Figure Description

[0019] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings: Figure 1 This is a system workflow diagram according to an embodiment of the present invention; Figure 2 This is a schematic diagram of the system structure according to an embodiment of the present invention; Figure 3 This is a schematic diagram of the spiral path according to an embodiment of the present invention; Figure 4 These are comparison images of powder steel before and after hardening in an embodiment of the present invention; Figure 5 These are property diagrams of various properties after welding according to an embodiment of the present invention; Figure 6 This is a schematic diagram of the welding mode according to an embodiment of the present invention; Figure 7 This is a simulation of the molten pool energy in a linear mode according to an embodiment of the present invention; Figure 8 This is a simulation of the molten pool energy for parameter 1 in Embodiment 1 of the present invention; Figure 9 This is a simulation of the molten pool energy for parameter 2 in Embodiment 2 of the present invention; Figure 10 This is a simulation of the molten pool energy for parameter 3 in Embodiment 3 of the present invention; Figure 11 This is a simulation of the molten pool energy for parameter 4 in Embodiment 4 of the present invention; Labeling descriptions: 100, System; 110, Control unit; 120, Laser output mechanism; 130, Information sensing mechanism; 140, Auxiliary mechanism; 1, Operating table; 2, Laser scanning galvanometer; 3, Laser generator; 4, Fiber optic cable; 5, Protective gas hood; 6, Gas hood opening; 7, Fixture; 8, Air source; 9, Air pipe. Detailed Implementation

[0020] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. This application will now be described in detail with reference to the accompanying drawings and embodiments.

[0021] It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions, and although a logical order is shown in the flowchart, in some cases the steps shown or described may be executed in a different order than that shown here.

[0022] Example 1 like Figure 1 and Figure 2 As shown, this embodiment provides an integrated laser processing system for cutting tools and scissors. The system 100 includes: a control unit 110, a laser output mechanism 120, an information sensing mechanism 130, and an auxiliary mechanism 140. The processing system enables the workpiece to be clamped in one go, and all tool processing steps are completed in the same laser output mechanism. The processing steps include integrated processing of pre-welding plate cleaning, plate welding, blade hardening, and plate cutting, which effectively improves production efficiency and product quality.

[0023] Furthermore, the control unit 110 is used to coordinate the cleaning, welding, hardening and cutting processes through program control, and automatically adjust the processing parameters based on sensor feedback; the laser output mechanism 120 is used to generate a laser beam according to the instructions of the control unit, and to rapidly deflect and precisely position the laser beam through a laser scanning galvanometer to complete each processing step; the information sensing mechanism 130 is used to collect plasma spectra and laser penetration images during processing, and to feed back the spectral signals and penetration status to the control unit; the auxiliary mechanism 140 is used to clamp the workpiece and provide inert protective gas and compressed air.

[0024] In a specific implementation of this embodiment, the control unit includes: a cleaning control module, used to automatically calculate and adjust the laser cleaning power based on the comparison results of the characteristic spectral information collected by laser-induced breakdown spectroscopy technology and the spectral characteristics of the substrate; a welding control module, used to automatically calculate and adjust the laser welding power based on the comparison results of the penetration state and the moderate penetration state identified by the pinhole image; a hardening control module, used to automatically calculate and adjust the laser defocusing amount based on the comparison results of the penetration state and the just-penetrated state identified by the pinhole image, wherein the laser power used for hardening is consistent with the welding power; and a cutting control module, used to automatically calculate and adjust the laser cutting power based on the comparison results of the penetration state and the over-penetrated state identified by the pinhole image.

[0025] As a specific implementation method of this embodiment, the implementation process of the control unit includes: the control unit uses a PLC program on the operating console 1 to realize intelligent collaborative control of the integrated processing process itself and between different processes. The control unit senses the processing process through multiple sensors. Before welding, the plate cleaning process collects characteristic spectral information through laser-induced breakdown spectroscopy technology to realize feedback of the cleaning process. The plate welding, blade hardening, and plate cutting processes use pinhole image recognition to identify whether the penetration is adequate to realize feedback of the welding process.

[0026] Furthermore, the plate cleaning process automatically calculates and adjusts the laser power by monitoring and comparing the spectral characteristics with those of the matrix; the plate welding process automatically calculates and adjusts the power by monitoring the pinhole penetration state, ensuring that the pinhole penetration state in plate welding is moderate, i.e., a stable pinhole penetration state; the blade hardening process automatically calculates and adjusts the defocusing amount by monitoring the pinhole penetration state, with the laser power used for blade hardening being consistent with the aforementioned welding power, and the pinhole penetration state in the hardening process being just penetration, controlled by the defocusing amount; the cutting process automatically calculates and adjusts the laser power by monitoring the pinhole penetration state, ensuring that the pinhole penetration state in cutting is over-penetration, such as... Figure 4 The comparison image of powder steel before and after hardening shows that before laser melting and hardening, its microstructure is a ferrite matrix with spherical carbides dispersed on it; after laser remelting, its microstructure is a martensitic matrix with a network of carbides distributed on it.

[0027] As a specific implementation of this embodiment, the laser output mechanism includes: a laser for generating laser light; an optical fiber for transmitting the laser light generated by the laser; a laser scanning galvanometer connected to the optical fiber for receiving the laser beam and realizing rapid deflection and precise positioning of the laser beam; and a coaxial dichroic mirror disposed on the laser scanning galvanometer for collecting plasma spectra and laser melting images generated during the processing.

[0028] As a specific implementation of this embodiment, the implementation process of the laser output mechanism includes: the laser output mechanism includes a laser scanning galvanometer 2 and a laser generator 3. The laser generator 3 is connected to the laser scanning galvanometer 2 via an optical fiber 4. The laser scanning galvanometer 2 can achieve rapid deflection and precise positioning of the laser beam, allowing the machine to remain stationary, reducing the response time of the mechanical mechanism, and improving welding accuracy. The laser scanning galvanometer 2 is equipped with a coaxial dichroic mirror for collecting plasma spectra. The laser penetration image is analyzed by the system for spectral signal analysis and keyhole penetration state analysis. The focal length of the focusing lens of the laser galvanometer is greater than 300mm. Figure 6 This is a schematic diagram of the welding mode.

[0029] As a specific implementation of this embodiment, the auxiliary mechanism includes: a motion mechanism for carrying and moving the workpiece to the laser processing area; a gas auxiliary mechanism including a gas source providing inert protective gas and a gas source providing compressed air; a solenoid valve disposed at the gas source outlet for controlling the switching of the gas passage; and a pressure sensor disposed at the gas source outlet for monitoring the gas pressure.

[0030] As a specific implementation of this embodiment, the implementation process of the auxiliary mechanism includes: the auxiliary mechanism includes a motion mechanism such as a mechanical wall or robot, and a gas auxiliary mechanism. The gas source 8 in the gas auxiliary mechanism consists of two parts: one is an inert protective gas used in the welding and hardening process, and the other is a compressed air source used for auxiliary cleaning, cooling of welding materials, and auxiliary laser cutting. Each gas source outlet is equipped with a solenoid valve and a pressure sensor, both of which are connected to a PLC. The PLC controls the gas switching according to process switching instructions through programming. To better achieve the protection effect, additional features can be configured as follows: Figure 2 As shown, the protective gas cover 5 of the gas tube 9 provides better protection for the cutting tool. The protective cover is semi-enclosed and has a gas cover opening 6 on top to facilitate laser processing. The gas cover is designed based on the principle that argon gas is denser than air, and argon gas is introduced in advance to expel air.

[0031] In this specific implementation, the processing steps are performed sequentially using the same scanning galvanometer, with different processing steps achieved only by changing process parameters such as the laser processing mode, laser path, laser scanning speed, and power. Preferably, the laser cleaning and blade hardening processes use a pulsed laser mode, while the welding and plate cutting processes use a continuous laser mode; the selection of the laser mode is automatically switched by the PLC programming control module inside the laser.

[0032] As a specific implementation of this embodiment, the processing steps include laser cleaning, laser welding, laser remelting and hardening, and laser cutting. The processing parameters can be edited once on the control unit to control the positioning, path, power, and processing speed of the four steps.

[0033] Laser processing achieves different process conditions through energy density control. The following formula is used to fit the required process parameters and set them: (1) (2) (3) (4) (5) Where f is the frequency, v is the scanning speed, A is the oscillation amplitude, and d is the spacing between the spirals. t is time, x0 and y0 are the coordinates of the origin, r0 is the spot radius, x is the position variable in the x-direction, and y is the position variable in the y-direction. For the energy utilization rate of laser, The dynamic x-position function of the laser varies with time. Let y be the time-varying dynamic position function of the laser. Let T be the total energy input at the spatial point (x, y), and T be the upper limit of the time for energy integration.

[0034] The laser welding and hardening process utilizes laser oscillation scanning. The laser oscillation trajectory is set via software, forming a spiral shape. The linear velocity is 300mm / s-600mm / s, the power is 2400w-4000w, the laser focal spot size is 0.2mm-0.6mm, the spiral oscillation amplitude is 0.5-2mm, and the laser spot diameter is 0.3mm-0.5mm. Figure 3 As shown.

[0035] To better meet the performance requirements of the knives and scissors, dissimilar steels are used, which are two steels with different physical properties selected according to the needs of the blade and the cutting edge. The difficulty in welding dissimilar steels lies in two aspects: First, the different coefficients of linear expansion of the dissimilar steels cause uneven expansion during welding and contraction during cooling, leading to excessive internal stress. This embodiment uses spiral welding to slow down the cooling time of the two steels to some extent, and the spiral welding also provides repeated heating to the processed area, reducing excessive internal stress caused by rapid cooling. Second, due to the significant difference in physical properties, dissimilar steel welding can result in uneven melting at one end and incomplete melting at the other. This solution addresses this problem through preheating the material with the higher melting point and controlling the welding path.

[0036] Preferably, the blade is made of conventional 304 stainless steel, which has excellent overall performance in terms of corrosion resistance, high toughness, good weldability, and low cost, while the cutting edge is made of special steel with high hardness, such as M390 powder steel, and laser remelting hardening is applied to the cutting edge.

[0037] Example 2 This embodiment provides an integrated laser processing method for blades and scissors, applied to the system of Embodiment 1, including the following steps: S1 The plate to be welded is fixed on the fixture 7, and the fixture 7 is placed under the laser processing area; S2 The laser output mechanism is controlled by the control unit to perform integrated processing, and the information sensing mechanism detects and provides feedback. First, the surface of the plate to be welded is laser-cleaned by laser scanning; S3 The air gun is started to remove the residue from the previous cleaning step, preparing the protective gas for the next welding step; S4 The cleaned plate is welded using an oscillating laser; S5 The area that needs to be hardened is processed using an oscillating laser; S6 The protective gas is turned off and switched to compressed air to assist the laser cutting in the next step; S7 After completing the above steps, the welded plate is trimmed and cut using a laser galvanometer.

[0038] As a specific implementation method of this embodiment, it includes: (1) Surface treatment: Two types of stainless steel are used, namely 304 stainless steel and M390 powder steel. 304 is used as the blade material and M390 powder steel is used as the cutting edge. The size is 100mm×50mm×2mm. Helical oscillating scanning is adopted with a power of 240W, a galvanometer scanning speed of 300mm / s, and 0 defocus.

[0039] (2) Welding: The two stainless steel plates are spliced ​​together, fixed with a clamp, moved to the laser processing area, and welded. The welding parameters are 3600w, 300mm scanning speed, 1mm swing amplitude, 0.4mm spiral spacing, 0.5mm beam spot radius, and 0 defocus.

[0040] (3) Weld hardening: After welding, the workpiece is moved 2.5mm along the M390 base material and then laser processing is continued to obtain a hardened area. The laser parameters are 3600w, scanning speed of 300mm, oscillation amplitude of 4mm, helical spacing of 0.4mm, spot radius of 0.5mm, and 0 defocusing. A hardened cutting edge area with a width of 4~4.5mm can be obtained.

[0041] (4) Plate cutting: The hardened plate is cut along the boundary between the hardened and unhardened areas using a laser. The laser power is 2500w-3000w and the beam movement speed is 20mm / s-40mm / s.

[0042] Example 3 This embodiment provides a laser processing method for integrated blade and scissor operation, including the following steps: (1) Surface treatment: M390 powder steel is treated separately with a power of 300W, a scanning speed of 300mm / s, a defocusing amount of +1mm, a spiral oscillating scanning method, a processing area of ​​100mm×50mm, and a plate thickness of 2mm.

[0043] (2) Welding: Since the same material is used, the welding process is the same as in Example 2.

[0044] (3) Remelting and hardening: Select the required area of ​​the cleaned M390 plate for laser remelting and hardening. (4) Laser cutting: Using a laser to cut along the boundary between the hardened and unhardened areas, the laser power is 2500w-3000w, and the beam movement speed is 20mm / s-40mm / s. High-hardness martensitic stainless steel can be obtained.

[0045] Example 4 This embodiment provides a method for efficiently processing dissimilar steel materials used in knives and scissors, which includes the following steps: (1) Surface treatment: Two types of stainless steel are used, namely 304 stainless steel and M390 powder steel. 304 is used as the blade material and M390 powder steel is used as the cutting edge. The size is 100mm×50mm×2mm. Helical oscillating scanning is adopted with a power of 240W, a galvanometer scanning speed of 300mm / s, and 0 defocus.

[0046] (2) Welding: The two stainless steel plates are spliced ​​together, fixed with a clamp, moved to the laser processing area, and welded. The welding parameters are 4000w, 350mm scanning speed, 1.5mm swing amplitude, 0.4mm spiral spacing, 0.5mm beam spot radius, and 0 defocus.

[0047] (3) Weld hardening: After cleaning, the M390 powder steel is moved 2.7mm along the edge and then processed by laser to obtain a hardened area. The laser parameters are 4000w, scanning speed of 350mm, oscillation amplitude of 4mm, spiral spacing of 0.4mm, spot radius of 0.5mm, and defocusing amount of 0. A hardened cutting edge area with a width of 4~4.5mm can be obtained.

[0048] (4) Plate cutting: The hardened plate is cut along the boundary between the hardened and unhardened areas using a laser. The laser power is 2500w-3000w and the beam movement speed is 20mm / s-40mm / s.

[0049] Table 1 shows the processing results of Embodiments 2, 3 and 4 of the present invention. Figure 5 The properties after welding are as follows: the tensile strength of the dissimilar steel weld joint is 644 MPa, the elongation after fracture is 12%, while the hardness of M390 powder steel before laser melting is 300 HV and after melting is 650 HV.

[0050] Table 1 As shown in the table above, within the given process range, the mechanical properties of the obtained joints are relatively stable and do not differ significantly, all consistently yielding welded joints with a strength exceeding 600 MPa. Furthermore, the hardened region values ​​are also relatively stable within the process parameter range. Moreover, this method is not limited to welding; it can also be used for heat treatment of sheet metal, thus having a wide range of applications.

[0051] Table 2 shows the energy parameters under process parameter control.

[0052] Table 2 This invention realizes four independent processes of "cleaning-welding-hardening-cutting" through the same galvanometer laser system, which solves the problem of "multiple equipment, multiple processes, and multiple clamping" in traditional knife and scissor manufacturing. At the same time, it solves the drawbacks of traditional electric arc welding and resistance welding processes, such as large heat input, difficult deformation control, and long post-weld processing chain. It not only improves processing efficiency but also improves processing quality and reduces processing costs.

[0053] This invention optimizes cleaning efficiency, weld penetration, hardened layer uniformity, and cutting precision by adjusting laser power density through parameters such as laser scanning path, power, and scanning speed. Unlike other laser cleaning patents, the laser cleaning described in this invention not only removes surface contaminants but, more importantly, removes the dense oxide layer on the metal surface. This requires significantly higher laser energy than conventional laser cleaning processes, eliminating steps such as acid / alkali washing. The hardening process differs from conventional laser hardening, which is essentially a surface strengthening heat treatment. Conventional laser hardening primarily involves heating the material surface to induce a phase transition and hardness change, without melting the material itself. This invention, however, uses process parameters to control the laser energy density, causing the material to melt and then solidify. By adjusting the oscillation amplitude, the remelting area can be significantly increased, and by adjusting parameters such as power and speed, the remelting depth or complete remelting can be achieved. This process is more difficult to control. Figures 7-11 This is a diagram showing laser energy regulation.

[0054] This invention uses a coaxial dichroic mirror set in the galvanometer to collect plasma spectra, and the laser penetration image is used for spectral signal analysis and pinhole penetration state analysis.

[0055] Knives and scissors are products with large usage volumes and a high degree of standardization. This invention can shorten the production cycle, reduce costs, and improve product quality, and has significant industrial application value.

[0056] Unlike assembly line processing, the processing in this invention is completed by a single machine. This machine not only intelligently controls its parameters but also utilizes the residual heat from the previous process through short-duration process transitions to achieve synergistic effects. The processes are not simply sequentially superimposed but rather complement and optimize each other. In this invention, the spiral scanning path of the cleaning process not only removes the oxide layer but also provides a uniform heat input foundation for the welding process; the oscillating laser in the welding process not only controls the penetration depth but also improves welding quality through stirring; and the defocusing control in the hardening process not only increases hardness but also enhances the impact resistance and durability of the cutting tool, providing a stable cutting edge structure for the cutting process.

[0057] The above are merely preferred embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A laser processing system integrating knives and scissors, characterized in that, include: The control unit is used to coordinate the cleaning, welding, hardening and cutting processes through program control, and automatically adjust the processing parameters based on sensor feedback; The laser output mechanism is used to generate a laser beam according to the instructions of the control unit, and to quickly deflect and precisely position the laser beam through a laser scanning galvanometer to complete each processing step. The information sensing mechanism is used to collect plasma spectra and laser melting images during the processing, and to feed back the spectral signals and melting status to the control unit. Auxiliary mechanism for clamping workpieces and providing inert protective gas and compressed air.

2. The integrated laser processing system for knives and scissors according to claim 1, characterized in that, The control unit includes: The cleaning control module is used to automatically calculate and adjust the laser cleaning power based on the comparison results between the characteristic spectral information collected by laser-induced breakdown spectroscopy and the spectral characteristics of the matrix. The welding control module is used to automatically calculate and adjust the laser welding power based on the comparison between the penetration state and the moderate penetration state identified by the pinhole image. The hardening control module is used to automatically calculate and adjust the laser defocusing amount based on the comparison between the penetration state and the just-penetrated state identified by the pinhole image. The laser power used for hardening is the same as the welding power. The cutting control module is used to automatically calculate and adjust the laser cutting power based on the comparison between the penetration state and the over-penetration state identified by the pinhole image.

3. The integrated laser processing system for knives and scissors according to claim 1, characterized in that, The laser output mechanism includes: Laser, used to generate laser light; Optical fiber is used to transmit laser light generated by a laser. A laser scanning galvanometer, connected to an optical fiber, is used to receive the laser beam and achieve rapid deflection and precise positioning of the laser beam; A coaxial dichroic mirror, mounted on a laser scanning galvanometer, is used to collect plasma spectra and laser penetration images generated during the processing.

4. The integrated laser processing system for knives and scissors according to claim 3, characterized in that, The focal length of the focusing lens of the laser scanning galvanometer is greater than 300 mm.

5. The integrated laser processing system for knives and scissors according to claim 3, characterized in that, The auxiliary mechanism includes: The motion mechanism is used to carry and move the workpiece to the laser processing area; Gas-assisted mechanism, including a gas source that provides inert protective gas and a gas source that provides compressed air; A solenoid valve, located at the gas source outlet, is used to control the switching of gas passages. A pressure sensor is installed at the gas source outlet to monitor gas pressure.

6. The integrated laser processing system for knives and scissors according to claim 5, characterized in that, Both the solenoid valve and the pressure sensor are connected to the control unit, which controls the gas switching according to the process switching command.

7. The integrated laser processing system for knives and scissors according to claim 1, characterized in that, The cleaning and hardening processes performed by the laser output mechanism use pulsed laser mode, while the welding and cutting processes use continuous laser mode.

8. The integrated laser processing system for knives and scissors according to claim 1, characterized in that, The welding and hardening processes performed by the laser output mechanism are processed by laser oscillating scanning with a spiral trajectory. The oscillation amplitude of the spiral trajectory is 0.5 mm to 2 mm.

9. The method of the integrated laser processing system for knives and scissors according to claim 1, characterized in that, Includes the following steps: A laser processing system integrating knives and scissors is provided, the system comprising a control unit, a laser output mechanism, an information sensing mechanism, and an auxiliary mechanism; The workpiece to be processed is fixed on the fixture of the auxiliary mechanism; The laser output mechanism, in accordance with the instructions of the control unit, uses a laser beam to perform laser cleaning on the surface of the workpiece. In an inert protective gas environment, the laser output mechanism is used to perform laser welding on the cleaned workpiece area by laser oscillation scanning; The laser output mechanism employs laser oscillating scanning to perform laser remelting and hardening on specific areas of the workpiece. With the assistance of compressed air, the laser output mechanism uses a laser beam to perform laser cutting on the workpiece along a predetermined path; The laser cleaning, laser welding, laser remelting and hardening, and laser cutting processes are automatically adjusted by the control unit based on the spectral signals and melting state images fed back by the information sensing mechanism.

10. The method according to claim 9, characterized in that, The expression for automatically adjusting the laser processing parameters for each process is: ； ； ； ； ； in, f For frequency, v For scanning speed, A For the amplitude of the oscillation, d The spacing between the spirals, t For time, x 0 、y 0 The coordinates of the origin are... r 0 Let be the radius of the light spot, x be the position variable in the x-direction, and y be the position variable in the y-direction. For the energy utilization rate of laser, The dynamic x-position function of the laser varies with time. Let y be the time-varying dynamic position function of the laser. Let T be the total energy input at the spatial point (x, y), and T be the upper limit of the time for energy integration.

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