• Title/Summary/Keyword: Sculptured part

Search Result 16, Processing Time 0.028 seconds

Manufacturing Feature Extraction for Sculptured Pocket Machining (Sculptured 포켓 가공을 위한 가공특징형상 추출)

  • 주재구;조현보
    • Proceedings of the Korean Society of Precision Engineering Conference
    • /
    • 1997.04a
    • /
    • pp.455-459
    • /
    • 1997
  • A methodology which supports the feature used from design to manufacturing for sculptured pocket is newly devlored and present. The information contents in a feature can be easily conveyed from one application to another in the manufacturing domain. However, the feature generated in one application may not be directly suitable for another whitout being modified with more information. Theobjective of the paper is to parsent the methodology of decomposing a bulky feature of sculptured pocket to be removed into compact features to be efficiently machined. In particular, the paper focuses on the two task: 1) to segment horizontally a bulky feature into intermediate features by determining the adequate depth of cut and cutter size and to generate the temporal precedence graph of the intermediate features and 2)to further decompose each intermediate feature vertical into smaller manufacturing features and to apply the variable feed rate to each small feature. The proposed method will provid better efficiency in machining time and cost than the classical method which uses a long string of NC codes necessary to remove a bulky fecture.

  • PDF

Tool Path Generation of a Die Cavity Defined by Sculptured Surfaces (자유곡면으로 이루어진 Cavity의 가공경로생성)

  • Jun, Yong-Tae;Park, Se-Hyung
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.10 no.3
    • /
    • pp.161-167
    • /
    • 1993
  • This paper deals with a new method for the machining of a die cavity defined by sculptured surfaces. In machining die cavities or pockets, process planners have been faced with some troulbes. One of the troubles ius to rebove a great deal of material within a given boundary while avoiding cutter interference. Cutter interference is a ciritical problem in NC machining of a die cavity. Even though this cavity machining has been implemented in many CAM systems, most of them can handle limited shapes of cavities or pockets. In this paper, a procedure has been developed to machine die cavity or pocket of a sculptured surface. The offset surfaces of the part surfaces and boundary surfaces are determined to calculate the intersection curves. These intersection curves form a FACE on the part surface, and the interference free tool pathe is generated by eliminating the points outside the FACE when computing the cutter contact (CC) data. Additionally, the cutter location (CL) data obtained from the CC data convert to an NC data. The NC data generated through this algorithm are verified on the CINCINNATI milling machine. A propotype die cavity machining system has been implemented in FORTRAN language and FIGARO graphics library on IRIS workstation.

  • PDF

A Study on the Machining of Sculptured Surfaces by 5-Axis CNC Milling (l) Cutter Axis Direction Verctor and Post-Processing (5-축 CNC 밀링으로의 자유곡면 가공에 관한 연구 (I) 공구축 방향의 벡터와 포스트 프로세싱)

  • 조현덕;전용태;양민양
    • Transactions of the Korean Society of Mechanical Engineers
    • /
    • v.17 no.8
    • /
    • pp.2001-2011
    • /
    • 1993
  • This study deals with the machining of sculptured surfaces on 5-axis CNC milling machine with end mill cutter. The study (I) has the following contents. In 5-axis CNC milling, CL-data consist of CC-data and cutter axis direction vector at the CC-point. Thus, in machining of the sculptured surface on 5-axis CNC milling machine, determination of the direction vector of the milling cutter is very important. The direction vector is obtained by the fact that bottom plane of the milling cutter must not interfere with the free-form surface being machined. The interference is checked by the z-map method which can be applied in all geometric types of the sculptured surfaces. After generating NC part programs from 5-axis post-processing algorithms, sculptured surfaces were machined with 5-axis CNC milling machine (CINCINNATI MILACRON, 20V-80). From these machining tests, it was shown that the machining of the free-form surfaces on 5-axis CNC milling machine with the end mill has smaller cusp heights and shorter cutting time than on 3-axis CNC milling machine with the ball-end mill. Thus, 5-axis CNC end milling was effective machining method for sculptured surfaces. The study (II) deals with the prediction of cusp height and the determination of tool path interval for the 5-axis machining of sculptured surfaces on the basis of study(I).

Automated machinability checking for sculptured surface manufacture

  • Kim, Kwangsoo;Ko, Byungchul
    • Proceedings of the Korean Operations and Management Science Society Conference
    • /
    • 1992.04b
    • /
    • pp.299-308
    • /
    • 1992
  • Determining tool-approach directions is an important issue when an effort is made to transfer CAD data into manufacturing automatically. An algorithm is developed to determine whether a given part can be machined on a three-axis milling machine. lf a set of feasible tool-approach directions exists for a sculptured surface, the NC tool path and G-codes for machining the surface on a three-axis milling machine can be generated automatically by an NC tool path generation algorithm. The algorithm can be used for orientation and fixturing of the workpiece for interference free machining. The algorithm can also be applied to checking the translational separability of polyhedral parts in automatic assembly.

  • PDF

A Study on CAM System for Machining of Sculptured Surface in Mold Cavity(1) - Generation of High Precision Machining Data for Curved Surfaces - (3차원 자유곡면 가공용 CAM시스템의 개발에 관한 연구(1) -고정도 곡면가상 정보 생성을 위한 이론적 고찰-)

  • 정희원;정재현
    • Journal of Advanced Marine Engineering and Technology
    • /
    • v.18 no.1
    • /
    • pp.92-100
    • /
    • 1994
  • For generating NC machining data automatically, it is important to handle computer models such as geometric shape data including engineering specifications for the mechanical part to be manufactured. We proposed unique CAM system for a personal computer that can define the geometric shape in an ease manner and machine the sculptured surfaces of a mold cavity. In this paper, the theoretical basis of generation of high precision machining data for a mold cavity is obtained. The first is geometric modelling, and the second is high precision machining with an optimized tool path algorithm satisfying given tolerance limits. Especially, the bicubic Bezier basis function is adopted for a geometric modelling.

  • PDF

Automatic Generation of Roughing Tool Path upon Unequal Level Line Matching (비균등분할 등고선 가공법에 의한 황삭가공경로의 자동생성)

  • Kim, Byeong-Hee
    • Journal of Industrial Technology
    • /
    • v.15
    • /
    • pp.23-32
    • /
    • 1995
  • The methodology of automatic generation of tool path for rough cutting of a sculptured surface is proposed with the improved contouring method, unequal level line machining. Considering the surface shape and the diameter of the endmill, the distance between level lines is obtained. To improve MMR, initial rough cutting is processed with the large diameter endmill and the remained material is removed by the relatively small diameter endmill. Tool path is generated from the offset curve of respective level line and the interferences between the tool and workpiece are automatically avoided. After generating NC part program, the sculptured surface is machined at the vertical machining center. From the experimental results, total cutting length and machining time are reduced more effectively than conventional contouring methods.

  • PDF

Mean Cutting Force Prediction in Ball-End Milling of Slanted Surface Using Force Map (볼엔드밀 경사면 가공에서 절삭력 맵을 이용한 평균절삭력 예측)

  • 김규만;주종남
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.15 no.12
    • /
    • pp.212-219
    • /
    • 1998
  • During machining of dies and molds with sculptured surfaces. the cutter contact area changes continuously and results in cutting force variation. In order to implement cutting force prediction model into a CAM system, an effective and fast method is necessary. In this paper. a new method is proposed to predict mean cutting force. The cutter contact area in the spherical part of the cutter is obtained using Z-map, and expressed by the grids on the cutter plane orthogonal to the cutter axis. New empirical cutting parameters were defined to describe the cutting force in the spherical part of cutter. Before the mean cutting force calculation, the cutting force density in each grid is calculated and saved to force map on the cutter plane. The mean cutting force in an arbitrary cutter contact area can be easily calculated by summing up the cutting force density of the engaged grid of the force map. The proposed method was verifed through the slotting and slanted surface machining with various inclination angles. It was shown that the mean force can be calculated fast and effectively through the proposed method for any geometry including sculptured surfaces with cusp marks and holes.

  • PDF

An unified rough and finish cut algorithm for NC machining of free form pockets with general polygon - Part 2. Experiment (일반적인 내벽을 가진 자유바닥 곡면 파켓의 NC 가공을 위한 단일화된 황삭과 정삭 알고리즘 - Part 2. Experiment)

  • Choi, Yong-Hoon;Kim, Sang-Jin
    • Journal of Korea Society of Industrial Information Systems
    • /
    • v.12 no.1
    • /
    • pp.46-53
    • /
    • 2007
  • NC (Numerical Control) code for the tool path needs to be generated efficiently for machining of free form pockets with arbitrary wall geometry on a three axis CNC machine. The unified rough and finish cut algorithm and the tool motion is graphically simulated in Part 1. In this paper, a grid based 3D navigation algorithm simulated in Part 1 for generating NC tool path data for both linear interpolation and a combination of linear and circular interpolation for three-axis CNC milling of general pockets with sculptured bottom surfaces is experimentally performed and verified.

  • PDF

Conservational Treatment and Deterioration Assessment of the Sculptured Standing Buddha Named Taehwa 4 Year in the Jincheon, Korea (진천태화4년명 마애불의 풍화훼손도 평가와 보존처리)

  • Lee, Chan Hee;Kim, Sun Duk;Han, Byeong Il;Kim, Yeong Taek;Lee, Myeong Seong
    • Journal of Conservation Science
    • /
    • v.16 s.16
    • /
    • pp.39-51
    • /
    • 2004
  • The standing Buddha named Taehwa 4 yew in the Jincheon were sculptured with rock cliff of the dark grey shale. Front of the Buddha statue shows $N40^{\circ}W$ strike with nearly vertical dip toward the back side. Rock blocks of the Buddha statue well developed with bedding and laminations whereas rock surface distributed into the various irregular discontinuities. Sculptured lines of the Buddha were uncertain because of degradation and exfoliations on the rock surface. The surface near the Buddha statue is highly contaminated with lichen and mosses, and accelerate physical and biological weathering owing to the roots of weed and bush along the fracture systems. For the conservational treatment, we treated with primary wet cleaning by air gun and secondary cleaning treatment using distilled water. Separated rock surface and fractured parts fasten and/or fill up the boundaries of the rock blocks using epoxy resin for conservation of rock properties. Some brittle surface was treatment with water repellent consolidant of ethyl silicates, and heterogeneous surface carried out color matching by acrylic pigments. Upper part of the Buddha statue dig out small ditch for rain water drainage, and near surface of the Buddha statue treat removal works for lichen, weeds and bush. The duration capacity of the Buddha constituting rocks are degraded by various weathering factors, therefore we suggest that this Buddha statue have need to do long term monitoring and synthetic conservation researches.

  • PDF

Cutter Interference Avoidance in NC Machining of Compound Surfaces (복합곡면 NC 가공에서의 공구간섭 방지)

  • Jun, Cha-Soo
    • Journal of Korean Institute of Industrial Engineers
    • /
    • v.19 no.3
    • /
    • pp.139-154
    • /
    • 1993
  • Cutter Interference(or part surface gouging) is one of the most critical problems in NC machining of sculptured surfaces. Presented in this paper is and algorithmic procedure that converts CC data obtained from a compound surface(several surfaces without topological relationship) into interference-free CL data. The interference handling procedure consists of following steps: (1) Z-map model is constructed from input surfaces. (2) Interference sources are detected using local properties of the sources. (3) Interference regions are completely identified based on global tests for neighboring CC points of the interference sources (4) Cutter paths are reconstructed after removing the CC data in interference regions, while avoiding any new interferences.

  • PDF