• Journal of the Korean Society for Precision Engineering
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• v.16 no.3 s.96
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• pp.9-17
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• 1999

This paper presents a method of grinding and polishing automation of precision die after CNC machining. The method employs a robot system equipped with a pneumatic spindle and a special abrasive film pad. The robot program is automatically generated off-line program form a PC and downloaded to robot controller. Position and orientation data for the program is supplied form cutter contact (CC) data of NC machining process. This eliminates separate robot teaching process. This paper aims at practical automation of die finishing process which is very time consuming and suffering from shortage of workpeople. Time loss due to changeover from one product to another is eliminated by PC off-line programming exploiting appropriate NC machining data. Dextrous 6-axis robot with rigid wrist and simple tooling enables the process applicable to larger, rather complex 3 dimensional free surfaces.

• Journal of the Korean Society for Precision Engineering
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• v.21 no.12
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• pp.52-59
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• 2004

This paper shows about the machine simulation embodiment when it happens NC equipment and between workpiece and interference in 5 axises machining of aluminium alloy a vehicles parts. And this research has been chosen because of the highest equipment interference occurrence rate at a vehicles parts processing of 5 axises horizontal machine. It can verify simulation and machining process through correlation of their dynamic relations, interference, collision as embodied virtual manufacturing system of machine, workpiece, and holder etc. That is necessary element in shape of machine tool, function and processing in imagination ball. Also, it verifies about interference and collision between NC equipment and workpiece, as it applied machine simulation to NC Data of actuality aircraft parts of BULKHEAD and FRAME. As the result of this study, by removing the equipment interference and collision element which creates NC data, the virtual machine tool it the efficiency of machine process has increased.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 2005.05a
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• pp.1101-1107
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• 2005

Mold industry has the difficulty to employ young people as the successors of the skilled workers, because it has been regarded as a 3D-jobs(dirty, difficult, and dangerous). To overcome this situation, thus, manufacturing technologies maintained in the factory should be systemized, and engineering systems should support unskilled workers to do their jobs without any difficulty. As a research of developing the supporting system, this study proposes a decision support system that facilitates unskilled workers to easily select high quality NC-data, as well as to increase productivity. The proposed system is assumed to follow a CAM operation scenario that consists of next three steps: 1) identifying several process plans and enumerating feasible unit machining operations (UMOs) from material and part surface information, 2) creating all feasible NC-data based on UMOs using a commercial CAM system, 3) selecting the best NC data among the feasible NC data using four screening criteria, such as machining accuracy, machining allowance, cutting load, and processing time. A case study on the machining of a camera core mold is provided to demonstrate the proposed system.

• Korean Journal of Computational Design and Engineering
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• v.8 no.1
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• pp.48-54
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• 2003

In a design-to-manufacturing environment, the product data is shared by various CAD/CAM/CAE systems with little integration or substantial data redundancy. The main purpose of this paper is to build a database containing all the features required for STEP-NC machining and to show how a STEP-NC repository can support the complete process for machining. A STEP-NC database schema has been constructed and several query functions have been built for the purpose of implementing the retrieving system of a STEP-NC database. The EXPRESS data model of ISO 14649 has been mapped to the database data definition language of the Oracle database. To apply the STEP-NC database to an industry example, the ISO 14649 part program has been stored into the STEP-NC database. To implement example scenarios, the sample query interface has been built.

• Journal of the Korean Society for Precision Engineering
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• v.15 no.7
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• pp.104-118
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• 1998

In this paper, the motion of ballscrew and shape of workpiece are the main objective variables varying with load conditions. To verify feed mechanism in NC lathe, the monitoring system is designed and cutting condition variables are spindle speed depth of cut and feed. During machining, rotation number of ballscrew motion of ballscrew in direction to gravity center and cutting force are measured. After machining, the roughness of workpiece is measured.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.18 no.33
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• pp.11-27
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• 1995

This study sets a goal of establishing work standard and standard time in a machine tool process consisted of high-priced NC machine tools. Firstly, the theories of work standard and standard time in the field of NC machine tools are studies. Secondly, the theories are actually applied to a manufacturing company; work standard sheets are developed and applied to a machining center haying low operation rate, and then the increase in productivity is compared. Finally, problems to be studied later in relation to work standard and standard time are presented.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.869-872
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• 2003

This paper presents a geometric machining simulation algorithm to enhance the reliability and user-friendliness of a comprehensive computer aided process planning (CAPP) system by verifying generated NC data. In order to represent the complex machining geometry with high accuracy, the proposed algorithm is developed based on a boundary representative (B-rep) solid modelling kernel. Solid models are used to represent the part geometry. tool swept volume and material removal volume by Boolean unite and subtract operations. By integrating a machining simulation procedure into the CAPP system, the systematic analysis of the tool path can be implemented synthetically. To demonstrate and check the validity of suggested system, a simple example of simulation is represented and the result is discussed.

• IE interfaces
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• v.12 no.1
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• pp.49-55
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• 1999

There are many types of holes to be machined on dies manufactured in the car industry. In this paper we introduce a CAM software developed for hole machining of press dies. The CAM software automatically generates NC files for machining holes from CAD data modeled in the CATIA system. A procedure generating NC files consists of three steps. First, the geometric information such as types of holes, hole positions, hole diameters, and hole depths is extracted from CATIA models. And then tools to be used and operation orders are standardized to establish a data base. Finally, NC files are generated by considering the machining conditions such as feedrate and rpm. It is efficient that holes with the same type and the same size should be grouped and machined by a tool to reduce the tool change time. The optimal tool path for machining the holes in a group can be determined by applying an algorithm solving the traveling salesman problem.

• Journal of the Korean Society for Precision Engineering
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• v.14 no.3
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• pp.114-121
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• 1997

In this paper, the automated initial process planning for 3-axis NC machining of sculptured surfaces is persented. The solution algorithms determining three process planning functions, i.e. machining feasibility, setup orientation and feasible machine selection are developed. The machining feasibility is determined by means of BSM(Binary Spherical Map) which derives its solution quickly in algebraic form, and the setup orientation is determined so that the cutting force is minimized. Finally, the feasible machine is determined by computing the minimum motion ranges of each control axisl. The developed algorithms are tested by numerical simulations, convincing they can by readily implemented on the CAD/CAM system as a process planner.

• Korean Journal of Computational Design and Engineering
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• v.12 no.1
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• pp.1-7
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• 2007

In this paper, we present a machining time estimation algorithm for 5-axis high-speed machining. Estimation of machining time plays an important role in process planning and production scheduling of a shop. In contrast to the rapid evolution of machine tools and controllers, machining time calculation is still based on simple algorithms of tool path length divided by input feedrates of NC data, with some additional factors from experience. We propose an algorithm based on 5-axis machine behavior in order to predict machining time more exactly. For this purpose, we first investigated the operational characteristics of 5-axis machines. Then, we defined some dominant factors, including feed angle that is an independent variable for machining speed. With these factors, we have developed a machining time calculation algorithm that has a good accuracy not only in 3-axis machining, but also in 5-axis high-speed machining.