Shaft part feature numerical control machining path generation method

Abstract

A numerical control machining path generation method for characteristics of shaft parts comprises the following steps: generating a rough machining path based on an attribute adjacency graph in combination with a geometric topology analysis technology according to the geometrical shape, the structural characteristics, a parameter list, a machining procedure, a selected cutter and a selected machining process of the parts; further correction is carried out based on a standardized process template matching and dynamic optimization algorithm technology to obtain a finish machining path, the finish machining path is verified based on a virtual simulation and interference inspection technology, and surface treatment is carried out. According to the method, full-automatic generation of the path from rough machining to finish machining is achieved through geometric shape and topology analysis, process template matching and a dynamic optimization algorithm, the machining path is verified through the virtual simulation and interference inspection technology, and high efficiency and reliability of the machining process are ensured.

Description

Technical Field

[0001] The present invention relates to a technology in the field of numerical control machining, specifically a method for generating a numerical control machining path for shaft part features. Background Art

[0002] In the existing methods for generating numerical control machining paths for shaft part features, traditional process design relies on manual experience, with low efficiency and high error rates. The degree of automation in numerical control process design is relatively low, and further optimization of path planning and dynamic adjustment of machining parameters are required. The existing template matching methods have insufficient adaptability to diverse and dynamic requirements, lacking flexibility and scalability. Summary of the Invention

[0003] Aiming at the problems in the prior art such as path generation relying on manual experience, low automation level, and insufficient accuracy, the present invention proposes a method for generating a numerical control machining path for shaft part features. By using geometric shape and topology analysis, process template matching, and dynamic optimization algorithms, it realizes the full-automatic generation of paths from rough machining to finish machining, and verifies the machining path through virtual simulation and interference checking technology to ensure the high efficiency and reliability of the machining process.

[0004] The present invention is realized through the following technical solutions:

[0005] The present invention relates to a method for generating a numerical control machining path for shaft part features. According to the geometric shape, structural features, parameter list, machining procedures of the part, as well as the selected tool and machining process, after generating a rough machining path based on the attribute adjacency graph combined with geometric topology analysis technology, a finish machining path is further corrected based on standardized process template matching and dynamic optimization algorithm technology, and the finish machining path is verified and surface treatment is carried out based on virtual simulation and interference checking technology.

[0006] For the rough machining path mentioned above, it mainly focuses on maximizing the material removal efficiency while ensuring uniform distribution of machining allowance, and is generated through the following methods:

[0007] Step 1: Establish a process database covering typical shaft part features based on prior knowledge.

[0008] The prior knowledge mentioned above refers to the knowledge accumulated by combining machining experience and industry standards, which is used to guide the establishment of the process database. The prior knowledge includes machining methods for machining features, selection of common tools, recommended cutting parameters, and typical machining sequences.

[0009] The process database includes: machining methods, applicable tools, recommended cutting parameters, and preferred machining sequences.

[0010] Step 2, Rough machining path matching: Analyze the geometric parameters of the shaft parts, and match the appropriate content in the process database according to the priority of feature machining, tool compatibility, and equipment capabilities to ensure the selection of the most suitable process.

[0011] The path matching mechanism mentioned above refers to the process of matching the feature parameters of the part with the templates in the process database. The basis of the matching mechanism includes feature type, size, priority, tool compatibility, and equipment capabilities. In this method, the role of the path matching mechanism is to quickly select the most suitable template for a specific machining task, reduce manual intervention, and improve the path planning efficiency.

[0012] Step 3, Rough machining path planning and adjustment: After generating the initial machining path according to the matched rough machining parameters, dynamically adjust it in combination with the machining capabilities of the specific equipment to avoid sudden changes in tool movement and ensure the path continuity and the smooth operation of the equipment.

[0013] For the dynamic adjustment mentioned above, the adjustment basis is to give priority to machining features that require a large amount of material removal to reduce the burden of subsequent processes; adjust the cutting depth and feed rate according to the material hardness, tool life, and equipment stability.

[0014] The finish machining path is generated in the following way:

[0015] Step a, Use the finish machining template in the process database to match the corresponding finish machining template in the process database according to the part state after rough machining and generate the initial finish machining path.

[0016] The finish machining template includes: small cutting depth, low feed rate, and smooth cutting direction, with a focus on optimizing surface quality and dimensional accuracy.

[0017] Step b, Considering tool wear, surface roughness requirements, and process limitations comprehensively, dynamically adjust the details of the initial finish machining path and generate the finish machining path for a single feature. Specifically: Ensure that the tool maintains the best cutting state when machining key areas, and adjust the cutting speed and cutting depth; for materials with high hardness or poor thermal conductivity, reduce the cutting parameters to reduce the heat affected zone; adjust the path to avoid high power output or equipment vibration.

[0018] Step c, Plan and generate the connection path between features in the finish machining path for a single feature, ensure smooth path transition, avoid time waste caused by multiple tool switches, and reduce the total machining time through global optimization.

[0019] The verified finish machining path is generated in the following way:

[0020] Step i, simulation and path visualization. Use the machining simulation to load the generated path, dynamically simulate the machining process in a virtual environment, intuitively verify whether the path meets the process requirements, and discover potential problems.

[0021] Step ii, interference and collision checking. Check whether the tool path interferes with the part, fixture, or other equipment components, and avoid machining obstacles by adjusting the path. Specifically for complex feature areas, accurately verify the tool movement range.

[0022] Step iii, machining efficiency analysis. Comprehensively evaluate the efficiency of the finish machining path. Simulate the machining time and tool service life. If there is room for optimization, return to the planning stage for adjustment to improve the overall machining efficiency. Technical effects

[0023] Through the integration of the attribute adjacency graph, geometric topology analysis, standardized process templates, and dynamic optimization algorithms, the whole process of path generation in the present invention realizes a high degree of automation. Combining the high-precision machining parameters of the finish machining template (such as small cutting depth and low feed rate) ensures the surface quality and dimensional accuracy of the machining results. Compared with the prior art, the present invention solves the problem of difficult formulation of machining solutions for complex features through comprehensive parametric processing and prior knowledge, and can flexibly adapt to a variety of machining scenarios. The machining efficiency is significantly improved, and the manual adjustment steps are replaced by automated processing. The optimization of the finish machining path improves the machining quality of the part and makes the machining process more reliable. Description of the drawings

[0024] Figure 1 is a flow chart of the present invention;

[0025] Figure 2 is a schematic diagram of the machining paths of each feature;

[0026] In the figure: (a) is the turning machining path with a straight rod-shaped feature, (b) is the turning machining path with a stepped feature, (c) is the milling machining path with a wrench groove feature, (d) is the EDM machining path with a V-shaped groove feature, (e) is the milling machining path with a keyway feature, (f) is the turning machining path with a relief groove feature, (g) is the EDM machining path with an internal hexagonal hole at the shaft end;

[0027] Figure 3 is a schematic diagram of the effect of the embodiment;

[0028] In the figure: (a) is a three-dimensional model display diagram of the embodiment, (b) is the simulation result of the generation path of the internal hexagonal hole at the shaft end, (c) is the simulation result of the generation path of the thread, (d) is the simulation result of the generation path of the relief groove, (e) is the simulation result of the generation path of the shaft end chamfer. Detailed implementation manners

[0029] Such asFigure 1 As shown in the figure, this embodiment relates to a method for generating a numerical control machining path for shaft part features. After setting multiple template codes according to machining prior knowledge, the final machining code and tool path file are generated based on specific part parameters and machining requirements to generate the numerical control machining path, which specifically includes:

[0030] Step 1: Establish a process database. Specifically include:

[0031] 1.1 Organize the machining process information of typical shaft part features (such as steps, grooves, holes, threads, etc.) through industry standards, expert experience accumulation, etc.

[0032] 1.2 Classify data items. Machining methods (turning, milling, drilling, etc.); tool selection (such as material, geometric parameters, tool model); recommended cutting parameters (cutting speed, feed rate, cutting depth); machining priority (priority according to the material removal amount, geometric complexity, and position arrangement of features).

[0033] 1.3 Data structure design. Adopt a modular approach to divide the above content into "machining feature templates", "tool templates", and "parameter templates", and establish corresponding association relationships.

[0034] Step 2: Generate rough machining paths, specifically including:

[0035] 2.1 Matching mechanism. According to the geometric shape and structural features of the part (such as diameter, depth, position, etc.), extract the feature parameters related to machining. Match the feature parameters with the machining feature templates in the process database, and the priority principle is to give priority to machining the features with a larger material removal amount. Select the tool according to the tool performance and part material. The matching result is to generate the preliminary tool path and machining parameters for rough machining.

[0036] 2.2 Path planning and adjustment. According to the matched templates and machining parameters, initially generate the path for removing materials, and adjust the machining parameters of the initially generated rough machining path. The output result is to generate an optimized rough machining path and provide a machining tool path file.

[0037] Step 3: Generate finish machining paths, specifically including:

[0038] 3.1 Machining template matching. Match through geometric parameters with the finish machining templates in the database, and select suitable tools and machining parameters (such as small cutting depth, low feed rate). Path initial generation. Utilize the trajectory rules and parameters defined in the template to generate a high-precision tool movement path.

[0039] 3.2 Dynamic parameter optimization. Optimize according to tool wear: Adjust the cutting speed and feed rate in real time to ensure that the tool is in the best cutting state.

[0040] 3.3 Coordination path generation. Coordinate all paths uniformly to reduce the total processing time and improve the overall efficiency.

[0041] Step 4: Verify the machining path. Use machining simulation software to load the generated rough machining and finish machining paths. Check whether the tool path interferes with the part, fixture or other equipment components.

[0042] As Figure 3 shown, through specific actual experiments, the CNC machining process of the external thread fixed unloading bolt is generated, and the machining path of its features is successfully obtained and verified by simulation.

[0043] Compared with the prior art, in the rough machining path generation stage, the present invention adopts the attribute adjacency graph combined with geometric topology analysis technology, which makes the recognition of the geometric shape and structural features of the part more accurate, shortens the path generation time, and greatly reduces the manual intervention time. In the finish machining path optimization stage, the standardized process template and dynamic optimization algorithm technology are adopted, which makes the cutting parameters more reasonable, improves the surface roughness, and enhances the path generation efficiency.

[0044] The above specific implementation can be locally adjusted by those skilled in the art in different ways without departing from the principles and purposes of the present invention. The protection scope of the present invention is subject to the claims and is not limited by the above specific implementation. All implementation solutions within its scope are subject to the present invention.

Claims

1. A method for generating a characteristic NC machining path for shaft parts, characterized in that: According to the geometric shape, structural features, parameter list, processing procedures, selected tools and processing technology of the parts, the rough machining path is generated based on the attribute adjacency graph combined with geometric topology analysis technology, and then the finishing path is further corrected based on standardized process template matching and dynamic optimization algorithm technology. The finishing path is verified based on virtual simulation and interference detection technology and surface treatment is performed.

2. The method for generating a characteristic NC machining path for shaft parts according to claim 1 is characterized in that: The roughing path described above focuses on maximizing the efficiency of material removal while ensuring uniform distribution of machining allowances, and is generated in the following way: Step 1: Establish a process database covering the features of typical shaft parts based on prior knowledge; Step 2: Rough machining path matching: Analyze the geometric parameters of shaft parts, match the appropriate content in the process database according to the priority of feature processing, tool compatibility and equipment capabilities, and ensure the selection of the most appropriate process; Step 3: Rough machining path planning and adjustment: After generating the initial machining path based on the matched rough machining parameters, it is dynamically adjusted in combination with the machining capabilities of the specific equipment to avoid sudden changes in the tool movement, ensuring path continuity and smooth equipment operation.

3. The method for generating a characteristic NC machining path for shaft parts according to claim 1, characterized in that: The finishing path is generated in the following way: Step a, using the finishing template in the process database, matching the finishing template in the corresponding process database according to the state of the part after rough machining and generating an initial finishing path; Step b, taking into account tool wear, surface roughness requirements and process limitations, dynamically adjust the details of the initial finishing path and generate a finishing path for a single feature, specifically: ensure that the tool maintains the best cutting state when machining critical areas, adjust the cutting speed and cutting depth; for materials with high hardness or poor thermal conductivity, reduce the cutting parameters to reduce the heat-affected zone; adjust the path to avoid high power output or equipment vibration; Step c: Plan and generate the connection paths between features in the finishing path of a single feature to ensure smooth path transition, avoid time waste caused by multiple tool switching, and reduce the total processing time through global optimization.

4. The method for generating a characteristic NC machining path for shaft parts according to claim 1, characterized in that: The verification finishing path is generated in the following way: Step i: Simulation and path visualization: Use machining simulation to load the generated path, dynamically simulate the machining process in a virtual environment, visually verify whether the path meets the process requirements, and identify potential problems; Step ii: Interference and collision check: check whether the tool path interferes with parts, fixtures or other equipment components, and avoid processing obstacles by adjusting the path, especially for complex feature areas, to accurately verify the tool motion range; Step iii: Processing efficiency analysis: comprehensively evaluate the efficiency of the finishing path, simulate the processing time and tool life, and if optimization space is found, return to the planning stage for adjustment to improve the overall processing efficiency.

5. The method for generating a characteristic NC machining path for shaft parts according to claim 2, characterized in that: The prior knowledge mentioned above refers to the knowledge accumulated in combination with processing experience and industry standards, which is used to guide the establishment of a process database. The prior knowledge includes processing methods of processing features, selection of commonly used tools, recommended cutting parameters and typical processing sequences.

6. The method for generating a characteristic NC machining path for shaft parts according to claim 2, characterized in that: The process database includes: processing methods, applicable tools, recommended cutting parameters and priority processing sequence.

7. The method for generating a characteristic NC machining path for shaft parts according to claim 2, characterized in that: The path matching mechanism refers to the process of matching the feature parameters of the part with the templates in the process database. The basis of the matching mechanism includes feature type, size, priority, tool compatibility and equipment capability. In this method, the role of the path matching mechanism is to quickly select the template that best suits a specific processing task, reduce manual intervention, and improve path planning efficiency.

8. The method for generating a characteristic NC machining path for shaft parts according to claim 2, characterized in that: The dynamic adjustment is based on the priority of processing features that require a large amount of material removal to reduce the burden on subsequent processes; the cutting depth and feed rate are adjusted according to the hardness of the material, the life of the tool and the stability of the equipment.

9. The method for generating a characteristic NC machining path for shaft parts according to claim 3, characterized in that: The finishing template includes: small cutting depth, low feed rate and smooth cutting direction, focusing on the optimization of surface quality and dimensional accuracy.

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