Tool-Path Generation for Conical Groove of Cylindrical Cams by Small-Sized Cutting Tools

2011 ◽  
Vol 189-193 ◽  
pp. 3046-3049
Author(s):  
Jui Pin Hung ◽  
Kuan Lin Chiu ◽  
Yuan Lung Lai

Instead of 2D expanding diagram method, this paper presents a new regenerating method for cutter location paths of using smaller tools to produce cylindrical cams. According to the expected motions, cams are put to use in various applications in mechanism. For a cylindrical cam, the roller follower operates in a groove cut on the periphery of an end mill with the diameter same as the roller. By using the conventional method, full-sized cutting tools, will restrict the flexibility of choosing cutting tools for wide roller guide. The manufacture of cylindrical cams is complicate and precise work that depends on the generating method and types of machine tools employed. Since the guiding curve cannot be offset exactly along the cylindrical surface, this leads to some approximating problems. Though the tool-paths generation by using the same size tools as rollers is applied in practice, the study of NC program by unequal tools is not available to meet high precision requirement. This proposed 3D offset-based generating method can regenerate tool-paths for standard cutting tools instead of larger ones and implemented on computerized CAM system. Examples with wider grooves are demonstrated to prove its effectiveness.

2021 ◽  
Author(s):  
Tianji Xing ◽  
Xuesen Zhao ◽  
Zhipeng Cui ◽  
Rongkai Tan ◽  
Tao Sun

Abstract The improvement of ultra-precision machining technology has significantly boosted the demand for the surface quality and surface accuracy of the workpieces to be machined. However, the geometric shapes of workpiece surfaces cannot be adequately manufactured with simple plane, cylindrical, or spherical surfaces because of their different applications in various fields. In this research, a method was proposed to generate tool paths for the machining of complex spherical surfaces based on an ultra-precise five-axis turning and milling machine with a C-Y-Z-X-B structure. Through the proposed tool path generation method, ultra-precise complex spherical surface machining was achieved. First, the complex spherical surface model was modeled and calculated, and then it was combined with the designed model to generate the tool path. Then the tool paths were generated with a numerically controlled (NC) program. Based on an ultra-precision three-coordinate measuring instrument and a white light interferometer, the machining accuracy of a workpiece surface was characterized, and t[1]he effectiveness of the provided tool path generation method was verified. The surface roughness of the machined workpiece was less than 90 nm. Furthermore, the surface roughness within the spherical region appeared to be less than 30 nm. The presented tool path generation method in this research produced ultra-precision spherical complex surfaces. The method could be applied to complex spherical surfaces with other characteristics.


Author(s):  
David Manuel Ochoa González ◽  
Joao Carlos Espindola Ferreira

Traditional (direction-parallel and contour-parallel) and non-traditional (trochoidal) tool paths are generated by specialized geometric algorithms based on the pocket shape and various parameters. However, the tool paths generated with those methods do not usually consider the required machining power. In this work, a method for generating power-aware tool paths is presented, which uses the power consumption estimation for the calculation of the tool path. A virtual milling system was developed to integrate with the tool path generation algorithm in order to obtain tool paths with precise power requirement control. The virtual milling system and the tests used to calibrate it are described within this article, as well as the proposed tool path generation algorithm. Results from machining a test pocket are presented, including the real and the estimated power requirements. Those results were compared with a contour-parallel tool path strategy, which has a shorter machining time but has higher in-process power consumption.


Author(s):  
Yuki Takanashi ◽  
Hideki Aoyama

Abstract Machining data (NC program) is generated by a CAM system, which generates the tool path from the target shape as a plane approximation surface instead of a free-form surface. Owing to this plane approximation, machining accuracy is reduced. In this paper, we propose a method to process the shape with high accuracy by defining the areas where accuracy is not required as a plane approximation surface and defining the part where accuracy is required as free-form surfaces.


Author(s):  
Edgar A. Mendoza López ◽  
Hugo I. Medellín Castillo ◽  
Dirk F. de Lange ◽  
Theo Lim

The CNC machining has been one of the most recurrent processes used for finishing NNS components. This paper presents a new method for the generation of tool paths for machining 3D NNS models. The proposed approach comprises two machining stages: rough cut and finish cut, and three types of cutting tools: ball-end mill, flat-end mill and fillet-end mill. The proposed tool path generation algorithm is based on: (1) approximation of the model surfaces by points using slice planes and visibility analysis, (2) accessibility analysis of the tool, (3) approximation error and tolerance evaluation, (4) collision analysis of tool and tool holder. The tools paths generated are exported as a CNC program. The implementation was carried out in C++ using the ACIS® geometric modeling kernel to support the required geometric operations. To prove the effectiveness of the system several models with variable geometric complexity were tested. The results have shown that the proposed system is effective and therefore can be used to generate the tool paths required for finishing 3D NNS components.


2010 ◽  
Vol 26-28 ◽  
pp. 982-987
Author(s):  
Xiu Ting Wei ◽  
Qiang Du ◽  
Jing Cheng Liu

The universal NC program was inefficient for machining centrifugal pump vanes and a new tool-path generation method along section lines was proposed in this paper. After analyzing curve characteristics of centrifugal pump vanes, the mathematical model for calculating cutting step-lengths and determining the next tool contact parameter ui+1 through step estimating method was put forward. Furthermore, a new iterative algorithm was implemented, along with its terminal condition simplified. The proposed algorithm provided a new idea for developing special NC program of impellers.


2015 ◽  
Vol 639 ◽  
pp. 517-524 ◽  
Author(s):  
Reginald Dewil ◽  
Pieter Vansteenwegen ◽  
Dirk Cattrysse

This paper deals with non-trivial problem aspects of laser cutting tool path generation that, to the best of our knowledge, received relatively little attention in the scientific literature. It is shown that some aspects such as plate edge nesting, skeleton and remnant cutting, and clamp positioning can be modeled and solved with little additional effort using existing tool path algorithms. However, concepts such as collision avoidance, pre-cut optimization, and bridge utilization prove to be more challenging and will require more profound algorithmic adjustments if these have to be taken into account fully. An even harder problem aspect is generating tool paths that are thermally feasible. Since laser cutting introduces net heat into the metal sheet, the metal sheet tends to heat up as the cutting progresses. Quality deterioration can occur if the laser spends too much time cutting in the same region. It is shown how to model the easy problem extensions in order to handle them using existing problem approaches and solution approaches are suggested to tackle the harder concepts. In addition, a proof of concept is presented that shows that thermal feasible tool paths can be generated through a multi-start heuristic utilizing a thermal penalty function. A finite difference method iteratively (or concurrently dependent on the used heuristic) evaluates the thermal feasibility and updates the penalty function.


2020 ◽  
Vol 14 (5) ◽  
pp. 808-815
Author(s):  
Koichi Morishige ◽  
Satoshi Mori ◽  
◽  

CAM software is generally used to generate tool paths for 5-axis controlled machining. However, adjusting its several parameters and settings is difficult. We propose a system for tool path generation to be applied to 5-axis controlled machining. The system allows machining movements to be established by manipulating haptic devices in a virtual environment. Therefore, the cutter location for 5-axis machining can be easily controlled by operating a virtual cutting tool. The contact between the cutting tool and the target shape is reflected to the user through the haptic device. The generated path can be converted into a numerical control program for the actual machining of the target object. We detail the implementation of the proposed interface using two haptic devices and a method of tool path generation that improves rough cutting by smoothing the generated cutting points and simplifying the tool postures. The effectiveness of the developed system is confirmed through machining simulations.


2008 ◽  
Vol 2008.4 (0) ◽  
pp. 177-178
Author(s):  
Yasuho AOKI ◽  
Hiroshi TACHIYA ◽  
Hiroshi YACHI ◽  
Yusuke MIYAZAKI

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