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Jung, Sung-Chan;Kim, Kug Weon
- Journal of the Korean Society of Manufacturing Process Engineers
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- v.4 no.4
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- pp.21-27
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- 2005
Recently researches for high speed machining have been actively performed. Few analytical studies, however, have been published. In this paper, a model of cutting forces is analytically studied to predict cutting characteristics in end mill process, especially considering both feed rate and spindle speed. The developed cutting model is based on Oxley's machining theory, which predicts the cutting forces from input data of workpiece material properties, tool geometry and cutting conditions. Experimental verification has been performed to verify the predictive cutting force model using tool dynamometer. It has been found that the simulation results substantially agree with experimental results.
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김철희;김전하;강명창;김정석
- Proceedings of the Korean Society of Machine Tool Engineers Conference
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- 2001.04a
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- pp.352-357
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- 2001
In this study, residual stress was investigated to evaluate damaged layer in high speed machining through simulation. In machining steel(STDll), residual stress remaining in machined surface was mainly appeared as compressive stress. The scale of this damaged layer more depends on feed per tooth and radial depth than spindle speed. Damaged layer was measured by optical microscope and hardness method. The micro-structure of damaged layer was a martensite because of cutting force and cutting temperature. Thickness of damaged layer is increased with incresing of feed per tooth and radial depth.
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이종렬;이준석;성승학;이득우
- Tribology and Lubricants
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- v.17 no.6
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- pp.476-481
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- 2001
This paper has been presented the hydrodynamic effect by the journal speed, eccentricity and source positions in order to overcome the defects of air bearing such as low stiffness and damping coefficient. Choosing the two row source position of air bearing is different from existed investigations in the side of pressure distribution of air film because of the high speed of journal and the wedge effects by the eccentricity. These optimal chooses of the two row source positions enable us to improve the performance of the film reaction force and loading force as making the high speed spindle. In this paper, The pressure behavior in theory of air film according to the eccentricity of journal and the source positions analyzed. The theoretical analysis have been identified by experiments. The results of investigated characteristics may be applied to precision devices like ultra-precision grinding machine and ultra high speed milling.
https://doi.org/10.9725/kstle.2001.17.6.476 인용 PDF

Kim, Sang-Uk;Kim, Jin-Hwan;Kim, Yong-Geun;Kim, Bo-Youl;Kim, Young-Bong
- Proceedings of the KIEE Conference
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- 2006.10b
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- pp.216-220
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- 2006
This paper is presented for the measurement of the bearing stiffness for the spindle motors. BLDC Spindle Motors for the Hard Disk Drive are used by several kinds of the bearings, such as ball bearing, fluid dynamic bearing, and aero dynamic bearing. The spindle motors are attached the platters to read and write the data. Because the platter rotates at high end speed with the load and can be shocked from a suddenly moving, the bearing needs the rated stiffness with the pressure. By the way, it has not been realized to measure the real stiffness for each bearing types. In this paper, we proposed the method of measuring the stiffness for the bearings by using the magnet force. Experimental results show the performance to measure the bearing stiffness of the BLDC spindle motors for an HDD.
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