• Journal of Korean Society of Industrial and Systems Engineering
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• v.27 no.2
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• pp.52-60
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• 2004

High-speed machining is one of the most effective technologies to improve productivity. Because of the high speed and high feed rate, high-speed machining can give great advantages for the machining of dies and molds. High speed machine tool makers try to find best machining condition with the one that they have built. Machine builders need to develop test specimen since it helps finding characteristics o( machine tools when the machining properties of the specimen are analyzed. This paper develops test specimen to identify features of the main spindle, the feeding device, and the frame of a machine tool.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2007.06a
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• pp.617-618
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• 2007

• Journal of the Korean Society for Precision Engineering
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• v.18 no.10
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• pp.208-213
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• 2001

High speed milling(HSM) is one of the emerging cutting process having tremendous potential not only in increased metal removal rates but also in improved surface finish, burr free edge, dimensional accuracy and a virtually stress free component after machining. The High efficiency and accuracy in machining of die/mold materials can be obtained in high speed machining, so it is necessary to analytic the mechanism of high speed cutting process : cutting force, acoustic emission signal.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.11a
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• pp.195-198
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• 2000

It can be acquired the high effective productivity through of high speed, precision of machine tools, and then, machine tools will be got a competitive power. Industrially advanced countries already developed that the high speed feed is 60m/min using the high speed ball screw. Also, a lot of problems have happened the feed drive system. It is necessary to study about the characteristics of thermal deformation played a more critical role than static stiffness and dynamic rigidity in controlling the level of machining accuracy. In spite of the improving the thermal deformation characteristics of machine tools at the design stage, there are always some residual errors that have to be compensated for during machining. In this study, thermal deformation error automated compensation device with multiple linear regression is proposed that thermal deformation error can be eliminated at the machining stage. The developed device has been practically applied to the feed drive unit.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.05a
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• pp.59-64
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• 2002

Recently the applications of high speed machining are increasing due to the need for high performance and high accuracy machining and machining for difficult-to-cut material. However, the high speed machining also accompanies some problems: the product quality can be degraded due to the tool wear and the product cast can go up due to frequent tool replacements. Therefore, it is necessary to develop a technique of quantitative tool wear measurement to determine the precise timing for tool replacement. In this respect, this study suggests a reliable technique far the reduction of error components by developing a system using a CCD camera and an exclusive jig to be able to precisely measure the size of tool wear in flat end mill for high speed machining.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2000.06a
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• pp.61-70
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• 2000

This paper described the current status of machine tool technology and its future trends with a particular emphasis on high-speed machining. People in machine tool industry have continuously sought to serve fast-changing manufacturing industry with economical machining solutins. At presents, it appears that more productivity gain is demanded to shorten time-to-market and machining requirements become more stringent. In this regard, this paper firstly addressed a high-speed spindle as a key element for the next-generation machine tools. The sequel to it apparently went to high-speed feed axes and final discussion included the problem of how to optimize overall system including servo function. Lastly a brief look to NC technology including machine intelligence was taken.

• Transactions of the Korean Society of Mechanical Engineers
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• v.17 no.2
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• pp.351-358
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• 1993

Recently a high speed spindle system for machine tools has attracted considerable attention to reduce the machining time, to improve the machining accuracy, to perform the machining of light metals and hard materials and to unite the cutting and grinding processes. In this study, a high speed spindle system is developed by applying the oil-air lubrication method, angular contact ball bearings, injection nozzles with dual orifices and so on. And a lubrication experiment for evaluating the performance of the spindle system is carried out. Especially, in order to establish the lubrication conditions related to the development of a high speed spindle system, the effects of oil supply rate, rotational spindle speed and so on are studied and discussed on the bearing temperature rise, bearing temperature distribution and frictional torque. And the effect of spindle system structure on the bearing temperature distribution is investigated.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.10a
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• pp.94-99
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• 2005

Though the technology on the ultra-precise machining has been developed intensively, the high speed and high precision for large machining range is still very hard to achieve. The linear motor system fur the universal machining center is proper fur high speed and high precision, but it has drawback of sensitivity to disturbance. In this research, two degrees of freedom controller based on the zero phase error tracking controller (ZPETC) and disturbance observer are proposed to improve the tracking performance and dynamic stiffness of linear motor system. The proposed controller is verified in simulations and experiments on a nano-positioner system, and the experimental result shows that the tracking performance improved. In addition, the PID optimization method is proposed for the commercialized controller such as the PMAC based system. The tracking as well as impedance is included in the cost function of optimization.

• Journal of the Korean Society for Precision Engineering
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• v.11 no.1
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• pp.123-128
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• 1994

A high speed spindle system for machine tools can be used to reduce the machining time, to improve the machining accuracy, to perform the machining of light metals and hard materials, and to unite the cutting and grinding processes. In this study, a high speed spindle system is developed by applying the oil-air lubrication method, angular contact ball bearings, injection nozzles with dual orifices, cooling jacket and so on. And an air cooling experiment for evaluating the performance of the spindle system is carried out. Especially, in ofder to establish the air cooling conditions related to the development of a high speed spindle system, the effects of cooling air pressure, oil supply rate, air supply rate and rotational spindle speed are studied and discussed on the bearing temperature rise and frictional torque. Also the effects of cooling air pressure, rotational spindle speed and spindle system structure is investigated on the bearing temperature distribution. The experiment on the test model reveals the usefulness of the air cooling method.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.10a
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• pp.483-488
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• 2000

This study aims at developing the high speed/intelligent machining system using the plug/play method of an open architecture controller. The plug/play technology by the application Specific Function (ASF), can readily implement the open architecture controller into various machining system or other automatic devices. The plug/play method integrates the ASF, visual builder, controller OS technology. This study, as an example, presents a schematic diagram for integration of an open architecture CNC and individual component technology for the high speed/intelligent machining system.