- Current status of technological development
At present, the main manufacturers of 3D five axis laser cutting machines include Trumpf in Germany, Prima in Italy, NTC in Japan, Mitsubishi in Japan, and Huagong Laser in China. Trumpf and Prima are highly recognized by market customers due to their early production, mature products, stable performance, and high market recognition. NTC and Mitsubishi in Japan only produce low speed and low acceleration 3D five axis CO2 laser cutting machines, which have low production efficiency and high energy consumption (CO2 lasers have very high energy consumption compared to fiber lasers), and cannot meet the production efficiency requirements of automotive hot forming production lines. Huagong Laser has broken through key technologies and mastered core technologies. It not only produces low-speed and high-precision 3D five-axis fiber laser cutting machines, but also produces high-speed and high-precision 3D five-axis fiber laser cutting machines. Its technology closely follows Trumpf and Prima, becoming a highly cost-effective product in the current market for 3D five-axis fiber laser cutting, solving the key core technology of 3D five-axis fiber laser cutting machines:
1. Optimization design and dynamic design of machine tool structure
Perform CAE finite element analysis on the structure of the entire machine, combining dynamic and static stiffness, static strength, and thermal characteristics to obtain the optimal stiffness and temperature fields for the entire machine. After repeated testing and verification, design improvements are made to analyze the differences between theoretical values and actual test data. When the theoretical values are basically consistent with the actual test data, an economical and lightweight structural design of the entire machine is ultimately obtained.
2. Improve dynamic performance and stability
Perform CAE finite element modal analysis on high-speed, large inertia, and large-sized components, analyze the damping, local stiffness, and mass distribution of the joint surface, take vibration isolation, vibration reduction, and suppression measures, design improvements and optimization of the structure, and obtain moving components with good dynamic performance and stability after repeated testing and verification, ensuring the dynamic performance and stability of the product. The modal analysis diagram is shown in the following figure.
3. Improve high-speed and high-precision positioning
Conduct testing and finite element analysis on the motor and servo feed drive system, analyze and optimize the positioning accuracy, response speed, thermal characteristics, and motor rigidity, and analyze the tracking characteristics to compensate for errors in the multi axis linkage of the CNC system, achieving high-speed and high-precision positioning. The analysis block diagram of the servo drive system is shown in Figure.
4. Solve the core technology of infinite rotation 3D cutting head
Precision optical calculations, formulation of spatial algorithms for system geometry, development of 360 ° wireless rotating 3D cutting heads, independent innovation, and core technology. It is the fourth manufacturer to produce 360 ° wireless rotating 3D cutting heads after Trumpf in Germany, Prima in Italy, and LT in Germany, breaking foreign technological monopolies.
For 3D five axis cutting head products, the following key and core technologies are addressed:
(1) Sealing of Water, Gas, and Light Paths in a 3D Five Axis Infinite Rotation Cutting Head
The motion trajectory of the three-dimensional five axis cutting head during machining is relatively complex, and the pipelines transmitted through the C-axis (infinite rotation) mechanical transmission part include optical, water, gas, and electrical signal pathways. Due to the infinite rotation structure of the C-axis, the above channels cannot adopt a pipeline structure, and a specific rotation channel structure needs to be designed for transmission. The following problem is to solve the dynamic sealing of water, gas, and light in the motion channel. To overcome this major obstacle, a rotating mechanical structure with independent transmission of water, gas, light, and electricity channels is selected among various alternative design options; To meet the technical requirements of sealing components for each rotating transmission path of the C-axis, a new type of material based design for rotating channel sealing components is developed. The component design fully considers the balance of comprehensive factors such as wear resistance, sealing performance, and dynamic friction between the components and the pipeline; Based on the guidance of theory and experience, adjust the tolerance fit between the sealing element and the sealed path appropriately, and successfully achieve a high-speed infinite rotation C-axis component that integrates multiple sealing transmission channels. After extensive experimental verification, the performance of the self-developed high-speed rotary sealing element has reached the level of similar foreign products.
(2) Anti-interference and shielding technology for electrical signals under high-speed rotation of three-dimensional cutting head.
Using traditional cables to transmit electrical signals in a rotating axis can cause the cable to wrap or even break due to the rotation of the axis. Simultaneous transmission of multiple electrical signals in small spaces also poses a risk of signal crosstalk. In order to avoid such problems and ensure the anti electromagnetic interference transmission of multi-channel electrical signals, according to the technical specifications of the multi-channel electrical signal path, a unique electric slip ring structure design has been pioneered, breaking through the anti interference transmission of multi-channel electrical signals on high-speed rotating shafts.
5. Online modification software technology
The online modification program software developed by Huagong Laser makes it more convenient and efficient to modify the program size, with fast replacement speed, improving production efficiency, and saving production costs.