• 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.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1997.10a
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• pp.47-51
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• 1997

The high speed machining which can improve the production and quality in machining has been adopted remarkably in dietmold industry. As the speed of machine tool spindle increases, the machinability evaluation and monitoring of high speed machining is necessary. In this study, the machinability of 30, 000rpm class spindle was evaluated by using the developed tool dynamometer and the machining properties of high hardened and toughness materials in high speed were examined. Finally, the in-process monitoring technologies of tool wear were presented through the prediction by the experimental formula and pattern recognition by the neural network.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2006.05a
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• pp.451-452
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• 2006

According to the demand of high productivity, the interest of manufacturing skills is growing in the industrial society. Especially the long spindle becomes important these days. The rotating accuracy of the spindle concerns the centrifugal force. In detail explaining, it is influenced by the speed of the spindle. In this study, we would show changes of the distance caused by a rotating speed of the spindle using a software, $ADAMS^{(R)}$. And because of the gravity of the spindle's mass, we would find the static droop of the long spindle.

• Journal of the Korean Society for Precision Engineering
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• v.18 no.8
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• pp.48-53
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• 2001

In order to increase productivity and efficiency, high-speed rotating machines become popular these days. The high-speed rotating machine is likely to vibrate and cause machine failure even though it has small unbalance. Therefore, a balancing technique is studied in this paper. Off-line balancing methods are inadequate to solve unbalance vibration problem occurring in the field due to flexible rotor effect, faster tool change, and shorter spin-up and down, etc. An active balancing is suggested to allow re-balancing of the entire rotating assembly in the machine when a tool is changed. This paper shows how to identify the dynamics of the system using influence coefficient and suggest an active balancing technique based on influence coefficient method for high-speed spindle system.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2002.10a
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• pp.141-146
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• 2002

Real-time monitoring and control of the cutting force is essential for unmanned cutting process. Although the cutting force can be measured directly using tool dynamometers, their implementation is not feasible in industry due to high cost. Alternative approach is the cutting force estimation based on spindle drive models, but it requires the knowledge of their characteristics with the spindle speed variation. This paper investigates the power-factor and frictional characteristics of three-phase induction motors and determines its characteristics below and above the base speed, respectively. In order to realize the proposed cutting force monitoring system, a stand-alone DSP board was utilized. Its monitoring and control performance is evaluated in a CNC lathe.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.21 no.5
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• pp.755-760
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• 2012

In this study, three dimensional cutting force components and surface roughness appeared in high speed cutting by using tungsten carbide endmill tools implanted ion or not found mutual relations through several analysis of statistical dispersion. It is showed that cutting force(Fx) is affect with spindle speed and feed rate, cutting force(Fy) is affect with spindle speed and ion implantation time and cutting force(Fz) is affect with feed rate in interaction through the statistical method of ANOVA of cutting force and surface roughness, it is analyzed that it is affected of spindle speed and feed rate in surface roughness.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.17 no.2
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• pp.7-12
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• 2008

In the design of modem rotating machinery, it is often necessary to increase the performance of rotor-bearing system. Since a critical speed range influences the performance and safety of the whole system, it should be necessary to constrain the critical speed and thus resonance response in design process to result in large vibration. Consequently the minimization of resonance response amplitudes within the operation range of the rotor system becomes the most primary design objective. In this paper, based on the assumption that the external shape of rotating-shaft, bearing supporting positions and etc, the natural frequency analysis of spindle is performed by ANSYS $10.0^{(R)}$ Optimum design is conducted using the RBF model.

• Journal of the Korean Society for Precision Engineering
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• v.29 no.5
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• pp.500-505
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• 2012

Recently, a high speed spindle is an essential part of machine tools to satisfy latest demand of high precision product and machining of hard materials. But, there are many disadvantages such as heat generation of built-in-motor, bearing friction, noise, vibration and displacement because of the high speed. Many researches on spindle systems have been conducted for solving these problems. In this study, technical trend of machine tools spindle systems are analyzed with patent PSM, mapping and grouping. The analysis is carried out for the applied patent during January 2000 and December 2009 in Korea, Japan, EU and U.S.A. And development of the direction, strategy and promising technologies of the spindle system are suggested.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.107-112
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• 2003

The recent machine tools are requested so high-quality processing and productivity increasing. Therefore, it is so necessary to develop technology for high-speed and high-precision. This thesis touches on the development of high speed and intellectual line center. At first, the line center is necessary that strong structure, compact structure and light weight design for high-speed processing and transfer. So, it is necessary that examination of new materials and structures for light-weight and control devices for precision processing. So, it is going to make mention of the process of 1st model production for the above-mentioned based on test model production and evaluation.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.26 no.1
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• pp.114-120
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• 2017

In recent years, applications of high speed rotating bodies have diversified. It is necessary for a device rotating at high speed to be balanced to minimize vibration. It is necessary to reduce the unbalancing factor to evenly wind the yarn. In this study, we also attempted to devise a technique to minimize the unbalance that occurs while assembling the components of spindles and to simplify the balancing procedure in the field. To balance the spindle, the vibration of the rotating spindle was measured using a laser displacement meter. We also performed balancing using the influence coefficient method by considering the phase.