A laser cutting device for sports equipment processing

Abstract

The application discloses a kind of sports equipment processing laser cutting equipment, including machine tool base, pipe conveying device, laser cutting head assembly, cooling assembly and pipe end face passivation processing assembly.Pipe conveying device realizes axial conveying by annular support frame cooperation clamping air cylinder and conveying roller assembly;Cooling assembly includes support table and a pair of cooling block, and the inner wall of the circular through-hole of cooling block is provided with at least two groups of cooling head groups of different cooling intensity along the axial direction;Laser cutting head assembly includes cutting head support fixed on cooling block and radially movable laser cutting head;Passivation processing assembly includes passivation liquid spray pipe that moves synchronously with laser cutting head.The application integrates pipe cutting, gradient cooling and notch protection function, eliminates hard and brittle tissue and inhibits intergranular corrosion by subarea differentiation cooling, simultaneously generates passivation film by using cutting residual heat, realizes cutting, tissue control, surface protection integrated processing.

Description

Technical Field

[0001] This invention relates to the field of pipe processing technology, specifically to a laser cutting device for processing sports equipment. Background Technology

[0002] In the sports equipment manufacturing industry, structural load-bearing components of fitness equipment such as barbell racks, squat racks, and cable machines are largely assembled from metal tubing that has been laser-cut and then welded together. After laser cutting, the cut ends and heat-affected zones of the tubing are at high temperatures, and the subsequent cooling process has a decisive impact on the microstructure and properties of the tubing ends.

[0003] Existing laser cutting equipment has significant problems with cooling the pipe ends after cutting. The equipment generally only uses a single set of uniform nozzles for overall cooling to facilitate subsequent handling, lacking the ability to perform differentiated cooling along the pipe's axial direction. This means that the cooling rate of each region from the cut edge towards the base material is entirely determined by natural heat dissipation and cannot be actively controlled. Typical microstructural damage resulting from this includes: for low-alloy steel pipes such as Q345, excessively rapid cooling near the cut leads to a hard and brittle microstructure, becoming a source of fatigue crack initiation; for 304 stainless steel pipes, the heat-affected zone remains within the sensitization temperature range of 450–850℃ for an extended period, causing chromium carbide precipitation along grain boundaries, resulting in decreased grain boundary corrosion resistance and susceptibility to intergranular corrosion in environments such as sweat or humid outdoor conditions common in sports equipment. Existing equipment cannot eliminate these microstructural defects by actively controlling the cooling rate gradient, nor can it utilize the residual heat of the pipe itself after laser cutting to simultaneously regulate the microstructure.

[0004] On the other hand, the exposed surface of fresh metal cuts after cutting is extremely prone to corrosion during turnover. In the existing processing mode, surface protection treatment needs to be carried out independently after the cutting process is completed. The separation of processes increases equipment investment and transfer cycle, and it is impossible to use the residual heat of cutting to accelerate the formation of the protective film.

[0005] Therefore, there is an urgent need for an integrated processing equipment that can simultaneously achieve regional gradient cooling of the tube end and surface protection treatment of the cut on a laser cutting device. Summary of the Invention

[0006] The purpose of this invention is to provide a laser cutting device for processing sports equipment, so as to solve the problems mentioned in the background art.

[0007] To solve the above-mentioned technical problems, the present invention provides the following technical solution: A laser cutting device for processing sports equipment includes a machine base, a pipe conveying device, a laser cutting head assembly, a cooling assembly, and a pipe end face passivation treatment assembly. The pipe conveying device includes at least one pair of annular support frames fixed to the machine base. The plane of each annular support frame is perpendicular to the pipe conveying direction. At least three radially extendable clamping drive members are evenly arranged circumferentially on the inner wall of each support frame. Each clamping drive member has a conveying roller assembly at its end for abutting and driving the pipe. The cooling assembly includes a support platform fixed to the machine base and a pair of cooling blocks spaced apart on the support platform along the pipe axial direction. Each cooling block has a circular through-hole for the pipe to pass through. At least two sets of cooling nozzles with different cooling intensities are arranged along the pipe axial direction on the inner wall of the circular through-hole. The laser cutting head assembly comprises a set of cooling nozzles, each set consisting of multiple cooling nozzles evenly distributed circumferentially along a circular through-hole. The pair of cooling blocks are located on opposite sides of the laser cutting area. The laser cutting head assembly includes a cutting head bracket fixedly connected to the pair of cooling blocks. The cutting head bracket is equipped with a movable block that can move in a direction perpendicular to the pipe axis, and the laser cutting head is fixed to the movable block. The pipe end passivation treatment assembly includes a passivation liquid spray pipe fixed to the movable block. The spray pipe is located on one side of the laser cutting head and moves synchronously with the movable block. It is used to spray passivation liquid into the cut after cutting.

[0008] Furthermore, the at least two sets of cooling nozzles include: a first set of cooling nozzles, located in a region 3-8 mm from the cut, wherein the spraying medium is high-pressure water mist or high-pressure inert gas, and the cooling rate is 500-2000℃ / s; and a second set of cooling nozzles, located in a region 8-15 mm from the cut, wherein the spraying medium is medium-pressure compressed air or medium-pressure inert gas, and the cooling rate is 100-500℃ / s.

[0009] Furthermore, it also includes a cooling medium supply system, which includes a cooling medium source and solenoid valves and flow valves independently configured for each group of cooling nozzles to independently control the cooling intensity of each group of cooling nozzles.

[0010] Furthermore, the clamping drive component is a clamping cylinder, and the conveying roller assembly includes a roller bracket fixed to the end of the clamping cylinder telescopic rod, a roller rotatably mounted on the roller bracket, and a motor fixed on the roller bracket for driving the roller to rotate; when each clamping cylinder extends synchronously, each roller abuts against the outer wall of the pipe, and the axial conveying of the pipe is achieved through the synchronous rotation of the roller.

[0011] Furthermore, the support platform is a hollow structure with several small holes on its top surface for waste liquid to flow in, and the edge of the top surface is inclined upward to guide the waste liquid to collect and flow into the small holes and prevent the waste liquid from overflowing. The bottom of the outer wall of the support platform is provided with a waste liquid outlet.

[0012] Furthermore, the cutting head support is provided with at least one pair of slide rails, the moving block is slidably sleeved on the slide rails, and a horizontal drive cylinder is also fixed on the cutting head support. The piston rod of the horizontal drive cylinder is connected to the moving block to drive the moving block to move in a direction perpendicular to the pipe axis.

[0013] Furthermore, the laser cutting head is a fiber laser cutting head with a laser power of 1500–3000W.

[0014] Furthermore, the pipe end passivation treatment assembly also includes a liquid storage chamber and a pump fixed on the cutting head bracket, with the liquid storage chamber, pump, and passivation liquid spray pipe connected in sequence; the passivation treatment liquid stored in the liquid storage chamber is a carbon steel pipe passivation and rust prevention liquid, and its components, by mass percentage, include: sodium benzoate 1.0-2.5%, triethanolamine 1.0-3.0%, sodium molybdate 0.3-0.8%, sodium carbonate 0.1-0.3%, alkylphenol polyoxyethylene ether 0.05-0.1%, with the balance being deionized water, and a pH value of 8.5-9.5.

[0015] Furthermore, the passivation solution is a chromium-free passivation solution for stainless steel pipes, and its components, by mass percentage, include: citric acid 4.0-8.0%, hydrogen peroxide with a mass concentration of 30% 2.0-5.0%, sodium molybdate 0.5-1.5%, cerium nitrate 0.1-0.5%, polyethylene glycol 400 0.5-1.0%, and the balance being deionized water.

[0016] Compared with the prior art, the beneficial effects of the present invention are: This invention utilizes fixed cooling blocks on both sides of the laser cutting area. Within each cooling block, at least two sets of cooling nozzles with different cooling intensities are arranged along the pipe's axial direction. These nozzles provide differentiated cooling to areas at different distances from the cut. The first set of nozzles, corresponding to the near-cut area (3-8 mm from the cut), provides strong cooling to achieve a fine-grained structure. The second set of nozzles, corresponding to the transition area (8-15 mm from the cut), provides moderate cooling to create a smooth hardness transition. Areas beyond 15 mm from the cut are naturally cooled, preserving the microstructure characteristics of the base material. This solution fundamentally changes the current technical limitations of laser cutting equipment where a single set of uniform nozzles cannot achieve gradient microstructure control. It proactively eliminates the hard and brittle microstructure formed at the cut edge of Q345 pipes due to excessively rapid cooling, avoids intergranular corrosion tendencies in the heat-affected zone of 304 stainless steel pipes caused by prolonged exposure to the sensitization temperature range, and achieves a smooth transition of mechanical properties from the cut edge towards the base material.

[0017] II. This invention integrates a cooling component, a laser cutting head component, and a pipe end passivation treatment component into a single unit. The cooling block also serves as the supporting foundation for the cutting head bracket, and the passivation liquid spray pipe is fixed to the moving block of the laser cutting head and sprays fluid accordingly. This structural design allows pipe cutting, gradient cooling, and cut protection to be completed simultaneously at the same workstation: during cutting, the passivation liquid spray pipe follows the laser cutting head, spraying passivation treatment liquid into the cut, utilizing the residual heat of cutting to accelerate the formation of the passivation film, eliminating the need for secondary pipe positioning or independent surface treatment processes. Compared to the traditional process where cutting and surface treatment are separated, this invention reduces equipment investment and inter-process transfer cycles, solves the problem of easy corrosion of exposed metal during turnover after cutting, and achieves integrated processing that combines cutting, microstructure control, and surface protection.

[0018] Third, the pipe conveying device of this invention employs a ring support frame in conjunction with clamping drive components and conveying roller assemblies evenly distributed along the circumference. Axial conveying of the pipe is achieved through the synchronous rotation of each roller. At least one pair of ring support frames is provided to maintain pipe stability during cutting. This conveying structure is adaptable to pipes with different cross-sectional shapes, the clamping force is adjustable and does not damage the pipe surface, ensuring the positioning accuracy of the pipe during cutting and cooling processes, and further guaranteeing the accuracy of gradient cooling zone division and the uniformity of passivation liquid spraying. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the overall structure of the present invention.

[0020] Figure 2 This is an enlarged view of section A of the overall structural schematic diagram of the present invention; Figure 3 This is a schematic diagram of the axial structure of the cooling block and the cutting head support of the present invention; Figure 4 This is a top view schematic diagram showing the positional relationship between the moving block, the slide rail, and the horizontal drive cylinder of the present invention. Figure 5 This is a schematic diagram of the top structure of the support platform of the present invention; Figure 6 This is a schematic diagram of the axial structure of the annular support frame of the present invention.

[0021] In the diagram: 1. Machine tool base; 2. Annular support frame; 3. Clamping cylinder; 4. Telescopic rod; 5. Roller bracket; 6. Roller; 7. Servo motor; 8. Support platform; 9. Cooling block; 10. Small hole; 11. Top edge; 12. Waste liquid outlet; 13. Circular through hole; 14. Cooling nozzle; 14a. First group of cooling nozzles; 14b. Second group of cooling nozzles; 15. Cooling medium source; 16. Solenoid valve; 17. Flow valve; 18. High-pressure water mist generator; 19. Compressed air source; 20. Control unit; 21. Cutting head bracket; 22. Slide rail; 23. Moving block; 24. Fiber laser cutting head; 25. Horizontal drive cylinder; 26. Auxiliary gas supply system; 27. Liquid storage chamber; 28. Pump; 29. ​​Passivation liquid spray pipe. Detailed Implementation

[0022] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0023] In the description of this invention, it should be noted that the terms "upper", "lower", "inner", "outer", "top", "bottom", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0024] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0025] Overall structure of the equipment like Figures 1-6 As shown, the present invention provides a laser cutting equipment for processing sports equipment, including a machine tool base 1, a pipe conveying device, a laser cutting head assembly, a cooling assembly, and a pipe end face passivation treatment assembly.

[0026] The pipe conveying device includes two pairs of annular support frames 2 fixed to the machine tool base 1. Each annular support frame 2 is located on one side of the cooling assembly and maintains a certain distance. The distance between the annular support frame 2 and the cooling block 9 is less than 1 / 3 of the total length of the pipe to ensure that the suspended end of the pipe does not sag significantly. The plane of each annular support frame 2 is perpendicular to the pipe conveying direction, and three clamping cylinders 3 are evenly arranged circumferentially on its inner wall. A roller bracket 5 is fixed to the end of the telescopic rod 4 of each clamping cylinder 3. A roller 6 is rotatably connected to the roller bracket 5 through bearings. A servo motor 7 for driving the roller 6 to rotate is also fixed on the roller bracket 5. When each clamping cylinder 3 extends synchronously, each roller 6 abuts against the outer wall of the pipe, and the roller 6 is driven to rotate synchronously by the servo motor 7 to realize the axial conveying of the pipe.

[0027] The cooling assembly includes a support platform 8 fixed to the machine tool base 1, and a pair of cooling blocks 9 spaced apart along the axial direction of the tube on the support platform 8. The support platform 8 is a hollow structure with several small holes 10 on its top surface for waste liquid to flow in, and the top edge 11 is inclined upward to guide the waste liquid to collect and flow into the small holes 10 and prevent the waste liquid from overflowing. A waste liquid outlet 12 is provided at the bottom of the outer wall of the support platform 8. Each cooling block 9 has a circular through hole 13 for the tube to pass through, and the central axis of the circular through hole 13 coincides with the central axis of the tube. Two sets of cooling nozzles with different cooling intensities are provided on the inner wall of the circular through hole 13 along the axial direction of the tube. Each set of cooling nozzles consists of eight cooling nozzles 14 evenly distributed around the circumference of the circular through hole 13. The two cooling blocks 9 are located on both sides of the laser cutting area, so that the tube on both sides of the cutting area can be cooled.

[0028] Two sets of cooling nozzles are arranged sequentially along the pipe axis. Specifically, the first set of cooling nozzles, 14a, corresponds to the area 3–8 mm from the cut, and its spray medium is high-pressure water mist with a cooling rate of 500–2000 °C / s. The second set of cooling nozzles, 14b, corresponds to the area 8–15 mm from the cut, and its spray medium is medium-pressure compressed air with a cooling rate of 100–500 °C / s. The area beyond 15 mm from the cut is the natural cooling zone.

[0029] The cooling medium supply system includes a cooling medium source 15, and a solenoid valve 16 and a flow valve 17 independently configured for each group of cooling nozzles. The cooling medium source 15 includes a high-pressure water mist generator 18 and a compressed air source 19. Each solenoid valve 16 and flow valve 17 is electrically connected to the equipment's control unit 20. The control unit 20 independently controls the cooling intensity of each group of cooling nozzles by adjusting the opening of each flow valve 17 according to a preset cooling program.

[0030] The laser cutting head assembly includes a cutting head bracket 21 fixedly connected above two cooling blocks 9. The cutting head bracket 21 spans the two cooling blocks 9 and is fixedly connected to them by bolts. The cutting head bracket 21 has two parallel slide rails 22 extending perpendicular to the pipe axis. A moving block 23 is slidably mounted on the slide rails 22, and a fiber laser cutting head 24 with a laser power of 2000W and an adjustable range of 1500–3000W is fixed to the bottom of the moving block 23. A horizontal drive cylinder 25 is also fixed to the cutting head bracket 21. The piston rod of the horizontal drive cylinder 25 is connected to the moving block 23 to drive the moving block 23 to move in a direction perpendicular to the pipe axis, thereby achieving radial feed of the fiber laser cutting head 24. The equipment also includes an auxiliary gas supply system 26 for supplying oxygen, nitrogen, or compressed air to the cutting area.

[0031] The tube end passivation treatment assembly includes a liquid storage chamber 27, a pump 28, a passivation liquid spray pipe 29, and the aforementioned waste liquid collection structure. The liquid storage chamber 27 and pump 28 are fixed to the cutting head support 21, and the passivation liquid spray pipe 29 is fixed to the moving block 23, located behind the fiber laser cutting head 24 along the cutting direction. The liquid storage chamber 27, pump 28, and passivation liquid spray pipe 29 are connected sequentially via pipelines. The passivation liquid spray pipe 29 moves synchronously with the moving block 23, spraying passivation liquid into the cut immediately after cutting. The hollow structure of the support platform 8 and the small holes 10 on its top surface are used to collect residual passivation liquid dripping during the spraying process.

[0032] Example 1: Laser cutting of Q345 carbon steel tubing barbell frame column This embodiment uses Q345 low alloy steel round tube (outer diameter 60mm, wall thickness 3mm) as the processing object. This tube is used for the upright component of the barbell rack of sports equipment, and it is necessary to cut and weld bevels at the tube ends.

[0033] The operator places the pipe on the pipe conveying device, and each clamping cylinder 3 extends synchronously. The roller 6 abuts against the outer wall of the pipe. The control unit 20 sets the air pressure of the clamping cylinder 3 according to the pipe wall thickness to control the maximum radial feed and prevent the thin-walled pipe from being deformed. The servo motor 7 drives the roller 6 to rotate, axially conveying the pipe to the cutting position.

[0034] The fiber laser cutting head 24 moves radially to the cutting start position under the action of the horizontal drive cylinder 25. The laser power is set to 2000W, and the auxiliary gas supply system 26 provides oxygen at a pressure of 6 bar. The fiber laser cutting head 24 feeds radially along the pipe to complete the pipe end beveling. During the cutting process, the passivation liquid spray pipe 29 sprays passivation treatment liquid onto the cut immediately following the fiber laser cutting head 24.

[0035] Meanwhile, the cooling blocks 9 on both sides of the pipe cutting area provide gradient cooling for the pipe. The first group of cooling nozzles 14a (3-8 mm from the cut) sprays high-pressure water mist at a flow rate of 4 L / min, with a cooling rate of approximately 800 °C / s; the second group of cooling nozzles 14b (8-15 mm from the cut) sprays medium-pressure compressed air at a flow rate of 80 L / min, with a cooling rate of approximately 200 °C / s; the area beyond 15 mm from the cut is naturally cooled, with a cooling rate of less than 100 °C / s.

[0036] In this embodiment, the passivation solution stored in the storage chamber 27 is a passivation and rust-preventing solution for carbon steel pipes. Its components, by mass percentage, are: sodium benzoate 1.8%, triethanolamine 2.0%, sodium molybdate 0.5%, sodium carbonate 0.2%, alkylphenol polyoxyethylene ether (OP-10) 0.08%, with the remainder being deionized water and a pH of 9.0. Pump 28 delivers the passivation solution to the passivation solution spray pipe 29 at a flow rate of 0.5 mL / s. Residual passivation solution dripping during spraying is guided and collected along the top edge 11 of the support platform 8, flows into the hollow structure of the support platform 8 through the small hole 10, and is discharged through the waste liquid outlet 12.

[0037] Example 2: Laser cutting of 304 stainless steel pipe gantry beam This embodiment uses a 304 stainless steel round tube (outer diameter 50mm, wall thickness 2mm) as the processing object. This tube is used for the crossbeam hanging pipe component of the gantry frame of fitness equipment.

[0038] The pipe clamping and conveying method is the same as in Example 1. The laser cutting parameters are set as follows: laser power 1800W, nitrogen gas supplied by auxiliary gas supply system 26, and pressure 10 bar.

[0039] During the gradient cooling process, the first group of cooling nozzles 14a (3-8 mm from the cut) sprays high-pressure nitrogen gas at a flow rate of 120 L / min, with a cooling rate of approximately 1500 °C / s, allowing the tube end material to quickly pass through the sensitization temperature range of 450-850 °C, effectively inhibiting the precipitation of chromium carbide along the grain boundaries; the second group of cooling nozzles 14b (8-15 mm from the cut) sprays medium-pressure nitrogen gas at a flow rate of 60 L / min, with a cooling rate of approximately 300 °C / s; the area beyond 15 mm from the cut is cooled naturally.

[0040] In this embodiment, the passivation solution stored in the storage chamber 27 is a chromium-free passivation solution for stainless steel pipes. Its components, by mass percentage, are: 6.0% citric acid, 3.5% hydrogen peroxide (30% mass concentration), 1.0% sodium molybdate, 0.3% cerium nitrate, 0.8% polyethylene glycol 400, and the balance being deionized water. Pump 28 delivers the passivation solution to the passivation solution spray pipe 29.

[0041] Comparative Example 1: Comparison of Uniform Cooling and Gradient Cooling This comparative example uses the same Q345 low-alloy steel round tube (outer diameter 60mm, wall thickness 3mm) as Example 1 as the processing object. The same equipment as in Example 1 is used, but the first cooling nozzle group 14a is shut down, and only the second cooling nozzle group 14b is turned on to use compressed air for overall cooling at a cooling rate of approximately 200℃ / s, simulating a conventional single-group uniform cooling method. Other cutting parameters (laser power 2000W, oxygen pressure 6bar) are the same as in Example 1. No passivation treatment is performed after cutting.

[0042] Comparative Example 2: Comparison of Offline Passivation Treatment and Online Passivation Treatment This comparative example uses the same Q345 low-alloy steel round tube as Example 1 as the processing object. After laser cutting and gradient cooling (cooling parameters are the same as in Example 1), the tube is not subjected to online passivation treatment. Instead, the tube is removed and placed on a turnover rack. After 24 hours, a carbon steel tube passivation and rust prevention liquid with the same formula as in Example 1 is applied at a separate surface treatment station.

[0043] Comparative Example 3: Sensitization Comparison of Stainless Steel Tubing without Gradient Cooling This comparative example uses the same 304 stainless steel round tube (outer diameter 50mm, wall thickness 2mm) as in Example 2 as the processing object. The same equipment as in Example 2 is used, but the first group of cooling nozzles 14a is shut down, and only the second group of cooling nozzles 14b is turned on to use compressed air for overall cooling at a cooling rate of approximately 50℃ / s, simulating a conventional single-group uniform cooling method. All other cutting parameters are the same as in Example 2. No passivation treatment is performed after cutting.

[0044] Comparative Example 4: Comparison of Cut Protection Without Passivation Treatment This comparative example uses the same 304 stainless steel round tube as Example 2 as the processing object. The cutting and gradient cooling parameters are exactly the same as in Example 2, but the passivation liquid spraying treatment is not performed.

[0045] Comparison of detection methods and results The following tests were performed on the pipes after treatment in the above embodiments and comparative examples: (1) The hardness distribution was measured at different distances from the cut along the axial direction of the pipe using a microhardness tester; (2) The microstructure of the cut edge was observed using a metallographic microscope; (3) An indoor environmental placement test was conducted on the carbon steel pipes to observe the time of rust appearance; (4) A neutral salt spray test was conducted on the stainless steel pipes according to GB / T 10125, and the time of red rust appearance was recorded; (5) An oxalic acid electrolytic etching test was conducted on the stainless steel pipes according to GB / T 4334 to evaluate the tendency of intergranular corrosion; (6) A rotational bending fatigue test was conducted according to GB / T 4337 to determine the fatigue limit. The test results are shown in the table below.

[0046] As can be seen from the comparison in the table above: Compared with Comparative Example 1, gradient cooling in Example 1 eliminated the hard and brittle structure in the near-notch area caused by single-group uniform cooling, and the hardness distribution changed from steep to smooth transition, increasing the fatigue limit by about 34%.

[0047] Compared with Comparative Example 2, in Example 1, the online passivation process utilizes the residual heat from cutting to accelerate film formation and avoids the risk of corrosion during inter-process turnover, while in the offline passivation process, rust spots already appeared on the tube end before coating.

[0048] Compared with Comparative Example 3, in Example 2, the high-pressure nitrogen rapid cooling of the first group of cooling nozzles 14a enabled the tube end material to quickly pass through the sensitization temperature range, avoiding intergranular corrosion and extending the corrosion resistance time of the salt spray test by more than double.

[0049] Compared with Comparative Example 4, neither Example 2 showed a tendency for intergranular corrosion. However, the salt spray corrosion resistance time of Example 2, which was passivated, was significantly better than that of Comparative Example 4, which was not passivated, indicating that gradient cooling and passivation treatment have a synergistic protective effect.

[0050] The above embodiments and comparative examples show that the gradient cooling device and online passivation treatment component of the present invention work together to solve the problems of tissue damage caused by uncontrollable cooling after laser cutting and the problem of cut end face protection, respectively. Moreover, the two are integrated into the same device, realizing integrated processing of cutting, tissue regulation and surface protection.

[0051] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A laser cutting device for processing sports equipment, comprising a machine tool base, a pipe conveying device, a laser cutting head assembly, a cooling assembly, and a pipe end face passivation treatment assembly, characterized in that: The pipe conveying device includes at least one pair of annular support frames fixed on the machine tool base. The plane of each annular support frame is perpendicular to the pipe conveying direction. At least three radially retractable clamping drive members are uniformly arranged on the inner wall of each annular support frame along the circumference. Each clamping drive member has a conveying roller assembly at its end for abutting and driving the pipe. The cooling assembly includes a support platform fixed on the machine tool base, and a pair of cooling blocks spaced apart on the support platform along the axial direction of the tube. Each cooling block has a circular through hole for the tube to pass through. The inner wall of the circular through hole is provided with at least two sets of cooling nozzles with different cooling intensities along the axial direction of the tube. Each set of cooling nozzles consists of multiple cooling nozzles evenly distributed along the circumference of the circular through hole. The pair of cooling blocks are located on both sides of the laser cutting area. The laser cutting head assembly includes a cutting head bracket fixedly connected to the pair of cooling blocks. The cutting head bracket is provided with a movable block that can move along a direction perpendicular to the axis of the tube, and the laser cutting head is fixed on the movable block. The tube end passivation treatment assembly includes a passivation liquid spray pipe fixed on the moving block. The spray pipe is located on one side of the laser cutting head and moves synchronously with the moving block. It is used to spray passivation treatment liquid into the cut after cutting.

2. The laser cutting equipment for processing sports equipment according to claim 1, characterized in that: The at least two sets of cooling nozzles include: The first group of cooling nozzles is located in an area 3 to 8 mm away from the cut. The spraying medium is high-pressure water mist or high-pressure inert gas, and the cooling rate is 500 to 2000℃ / s. The second group of cooling nozzles is located in an area 8 to 15 mm from the cut. The spray medium is medium-pressure compressed air or medium-pressure inert gas, and the cooling rate is 100 to 500 °C / s.

3. The laser cutting equipment for processing sports equipment according to claim 2, characterized in that: It also includes a cooling medium supply system, which includes a cooling medium source and solenoid valves and flow valves independently configured for each group of cooling nozzles to independently control the cooling intensity of each group of cooling nozzles.

4. The laser cutting equipment for processing sports equipment according to claim 1, characterized in that: The clamping drive is a clamping cylinder, and the conveying roller assembly includes a roller bracket fixed to the end of the clamping cylinder telescopic rod, a roller rotatably mounted on the roller bracket, and a motor fixed on the roller bracket for driving the roller to rotate. When each clamping cylinder extends synchronously, each roller abuts against the outer wall of the pipe, and the axial conveying of the pipe is achieved through the synchronous rotation of the roller.

5. The laser cutting equipment for processing sports equipment according to claim 1, characterized in that: The support platform has a hollow structure with several small holes on its top surface for waste liquid to flow in, and the edge of the top surface is inclined upward to guide the waste liquid to flow into the small holes and prevent the waste liquid from overflowing. The bottom of the outer wall of the support platform is provided with a waste liquid discharge outlet.

6. The laser cutting equipment for processing sports equipment according to claim 1, characterized in that: The cutting head support is provided with at least one pair of slide rails, the moving block is slidably sleeved on the slide rails, and a horizontal drive cylinder is also fixed on the cutting head support. The piston rod of the horizontal drive cylinder is connected to the moving block to drive the moving block to move in a direction perpendicular to the pipe axis.

7. The laser cutting equipment for processing sports equipment according to claim 1, characterized in that: The laser cutting head is a fiber laser cutting head with a laser power of 1500-3000W.

8. The laser cutting equipment for processing sports equipment according to claim 1, characterized in that: The pipe end passivation treatment assembly also includes a liquid storage chamber and a pump fixed on the cutting head bracket. The liquid storage chamber, the pump, and the passivation liquid spray pipe are connected in sequence. The passivation treatment liquid stored in the liquid storage chamber is a carbon steel pipe passivation and rust prevention liquid. Its components, by mass percentage, include: sodium benzoate 1.0-2.5%, triethanolamine 1.0-3.0%, sodium molybdate 0.3-0.8%, sodium carbonate 0.1-0.3%, alkylphenol polyoxyethylene ether 0.05-0.1%, and the balance is deionized water with a pH value of 8.5-9.

5.

9. The laser cutting equipment for processing sports equipment according to claim 8, characterized in that: The passivation solution is a chromium-free passivation solution for stainless steel pipes, and its components, by mass percentage, include: citric acid 4.0-8.0%, hydrogen peroxide with a mass concentration of 30% 2.0-5.0%, sodium molybdate 0.5-1.5%, cerium nitrate 0.1-0.5%, polyethylene glycol 400 0.5-1.0%, and the balance being deionized water.

Images