• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 1993.04b
• /
• pp.127-130
• /
• 1993

최근 산업의 발전과함께 부품가공의 고능률화와 고품위화에 대한 요구가 높아지고 있으며, 이를 위한 공작기계의 고속, 고정도화에 관한 많은 연구가 수행되고 있다. 그 중에서 주축의 고속, 고정도화에 대한 연구는 NC 공작기계의발달과 함께 꾸준히 연구되어 왔으며 윤활방식, 구동방법, 냉각방법 등에 대한 연구결 과들이 보고되고 있다. 또한 최근의 공작기계는 다기능화 개념에 의한 복합가공기능이많이 첨가되고 있는데, 이에따라 저속에서부터 고속에까지 넓은 범위에서 사용 가능한 주축의 개발이 요구되고 있다. 본 연구에서는 공작기계용 모타내장형 주축의 열특성에 관련된 성능특성을 파악하여 모타내장형 주축의 설계 및 제작에 관련된 기초자료를 제공하고자 한다. 이를 위해모타내장형 시험주축을 제작하고, 운전조건에 따른 모타 및 베어링에 서의 온도및 열분표를 측정하여이들의 열거동을 추적하고 열특성을 파악한다.

• Proceedings of the KSME Conference
• /
• 2001.11a
• /
• pp.734-739
• /
• 2001

In this paper, we develop a six-axes machining center tool(MCT) and CAD/CAM system. The MCT consists of two mechanical parts, i.e., a X-Y-Z Cartesian coordinate typed MCT and a parallel-typed tilting table. Kinematics and singularity are accomplished to design the parallel-typed tilting table, and CAD/CAM system is developed for the six-axes MCT, which requires the commands of position as well as orientation for machining of complex shape. The CAD/CAM system has a tool path generator, a NC code generator and a graphic simulator. This paper designs the parallel-typed tilting table to meet the desired specification and presents the results of tool path, NC code and graphic simulation.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 1992.04a
• /
• pp.38-42
• /
• 1992

기계 가공 분야에 있어서의자동화 기술은 NC 장비로 인해 급격히 진전되고 있다. 대부분의 공작기계들이 NC화로 되는 것이 크게 증가하고 있으며 사회적 경제적 환경의 변화에 의해 합리적인 수준에서의 자동화를 추진하고자 하는 요구가 많아지고 있다. 본 연구에서는 선삭공정의 자동 화에 있어서 필연적으로 대두되는 공구 선택에 있어서 절삭공구에 대한 정보를 확률이론을 도입 하여 처리하여 신뢰성이 있는 최적공구를 선택할 수 있도록 한다.

• Journal of the Korean Society of Industry Convergence
• /
• v.3 no.2
• /
• pp.115-121
• /
• 2000

This paper presents reducing method of profile error on a mechanical tuning for multi-spindle control of NC machine tools. To reduce the profile error in the feed drive system, it is useful to adopt same transfer function of multi spindle machine tools. By selecting the correction vector of servo rigidity and natural vibration on JK map, multi spindle control can be tuned by mechanical parameters with small profile error.

• 제어로봇시스템학회:학술대회논문집
• /
• 1992.10a
• /
• pp.887-891
• /
• 1992

In this study, it is developed the interactive DNC(Direct Numerical Control) system, in using RS-232C cable and auxiliary computer, through the diagnosis of planning process and information evaluation. this DNC system recognize the Manufacturing planning and control it. This DNC system has a different notation. It can be done by an operator who hasn't knowledge about personnel computer. It is operated with automatic planning and measurement tec. by operator, using part program on the NC(Numerical Control).

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2003.06a
• /
• pp.1907-1910
• /
• 2003

Miniaturized machine tool can be used to produce 3D features based on CNC and PC-NC technology in the micro/meso scale. Wide applications of CNC technology are developed and there are lots of know-hows in the cutting process and their CNC application. It helps micro/meso scale structure to machine components, which can be used directly for practical applications. In the present research, as the machine tool is miniaturized, the manufacturing machine tools costs less when compared to the equipment used in other micromachining technologies. Moreover, with advancement of micro tool technology, the cutting process can be used to produce micro/meso scale parts. In conclusion, the proposed system can reduce the cost by utilizing the current machining technology, and as a result, complex micro/meso parts can be produced efficiently with high productivity.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
• /
• 2002.10a
• /
• pp.417-422
• /
• 2002

One of the major limitations of productivity and quality in metal cutting is the machining accuracy of machine tools. The machining accuracy is affected by geometric errors, thermally-induced errors, and the deterioration of the machine tools. Geometric and thermal errors of machine tools should be measured and compensated to manufacture high quality products. In metal cutting, the machining accuracy is more affected by thermal errors than by geometric errors. In this study, the compensation device and temperature-based algorithm have been implemented on the machining center in order to compensate thermal error of machine tools under the real-time. The thermal errors are predicted using the neural network and multi-regression modeling methods. In order to compensate thermal characteristics under several operating conditions, experiments performed with five gap sensors and manufactured compensation device on the horizontal machining center.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2002.10a
• /
• pp.999-1002
• /
• 2002

Cylindrical Cam Mechanism is widely used in the fields of industries, such as machine tool exchangers, textile machinery. This paper proposes a method for manufacturing of cylindrical cam in Multi CNC machining center. Multi CNC machining center has two different types depending on the tilting axis. For the manufacturing procedures. in this paper the location and the orientation of cutter path are defined from shape design data of cam. The integral NC code fur the both types of multi-axis CNC machining center can be created using the coordinates mapping between design coordinates and work coordinates. Finally, CAD/CAM program is developed on $C^{＋＋}$ language. This program can display manufacturing and kinematics simulation, which can make integral NC code for multi-axis CNC machining center of two types.

• Transactions of the Korean Society of Machine Tool Engineers
• /
• v.14 no.5
• /
• pp.21-26
• /
• 2005

It is important to measure the rotational accuracy of NC lathe spindle as it affects to the qualities of all machines machined by the NC lathe using in industries. The bad rotational accuracy of NC lathe spindle are caused mainly by wearness of the spindle in using and quality of spindle when machining and using low level bearings. It occurs especially in case of NC lathes because the cutting force acting to work-piece act on one side to the spindle not to both sides symmetrically. Therefore in this study, constructing experimental appratus for measuring of rotational accuracy by using eddy current type gap sensors, converters, screw terminal, data acquisition board inserted in computer and software f3r data acquisition, DT VEE ver. 5.0 and then error data acquired in the rotational accuracy test of NC lathe spindle are analysed in plots and statistical treatments.

• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.29 no.2 s.233
• /
• pp.311-317
• /
• 2005

NC controller parameters are fixed when the controller is combined with a machine. However, the characteristics of controller could be changed as it has being used by the machine or other environmental conditions. Ultimately, it results in tool positioning accuracy changing. The loading torque in servo motor also influences on the positioning accuracy. This study focus on a measuring and analysing method for verifying the angular positioning accuracy of NC servo motor. We used a high resolution A/D converter for acquiring analogue signal of rotary encoder in servo motor. Generating tool path by the combination of axial movements (X,Y,Z) is compared with the encoder signals with the servo motor torque. The current variation signal is also read from the servo motor power using a hall sensor and converted to the motor torque. The method of analysing proposed in this study will be used for determining the gains (tuning) of parameter in NC controller, when the controller is set up at a machine initially or the controller condition is changed during the work.