• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.05a
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• pp.46-51
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• 2002

A grinding technology is very essential to finish the surface of IT and BT industrial application parts such as wafer, optical connection part and lenses etc. However the finding machine has bead depended on imports. Especially, it is completely imported for machining high precision part relevant to domestic electric and communicational industries. The amount to import grinding machine is about $110milions. It takes about 35% of total import amount of all the machine tools. A domestic finder manufacturer is a very small-scaled bussinessman and research facilities is poor. Recently, it is increasing to demand high speed and precision grinding technology because it brings cost down and value added up. Its further study will be something related to inteligent grinding system fur value added and high precision part. It will make domestic grinding technology to its advanced country level.

• Journal of the Korean Society for Precision Engineering
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• v.32 no.8
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• pp.693-698
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• 2015

Recently, the quality of products after the corresponding machining processes were scrutinized in the interest of maintaining a high product-quality standard. The structure and stability of machine tools are important for the prediction of product quality. A structural analysis needs to be carried out to achieve the stable design of machine tools before the initial design stage in the manufacturing process of a precision product. In this study, a structural analysis was carried out using a finite element analysis (FEA) simulation to obtain the design stability of the main parts of a grinding machine. The sizes and locations of both the maximum stress and deformation in consideration of the cutting force of the chuck, tail stock, and bearing of the grinding machine were analyzed. Finally the grinding machine was successfully developed.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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• pp.946-949
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• 2001

Mirror surface finish of Si-wafers has been achieved by rotary in-feed machining with cup-type wheels in ELID grinding. But the diameter of the workpiece is limited with the diameter of the grinding wheel in the in-feed machining method. In this study, some grinding experiments by the rotary surface grinding machine with straight type wheels were conducted, by which the possible grinding area of the workpiece is independent of the diameter of the wheels. For the purpose of investigating the grinding characteristics of large scale diametral silicon wafer, grinding conditions such as rotation speed of grinding wheels and revolution of workpiece are varied, and grinding machine used in this experiment is rotary type surface grinding m/c equipped with an ELID unit. The surface ground using the SD8000 wheels showed that mirror like surface roughness can be attained near 2~6nm in Ra.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.30 no.12 s.255
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• pp.1634-1641
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• 2006

High-precision centerless grinding machines are emerging as a means of finishing the outer diameter grinding process required for ferrules, which are widely used as fiber optic connectors. In this study, a sensitivity analysis for structural and thermal characteristics was carried out using a virtual prototype of a centerless grinding machine to realize systematic design technology and performance improvements required to manufacture ferrules. The prototype consisted of a concrete-filled bed, hydrostatic grinding wheel (GW) and regulating wheel (RW) spindle systems, a hydrostatic RW table feed mechanism, a RW swivel mechanism, and on-machine GW and RW dressers. The results of the structural sensitivity analysis illustrated that the vertical stiffness of hydrostatic guideway for the RW table feed system greatly influenced the horizontal loop stiffness, and the results of the thermal sensitivity analysis illustrated that the heat generation rates at hydrostatic bearings and belt pulley greatly influenced the temperature rise of hydrostatic bearings and the deviation of thermal displacement between GW and RW.

• Journal of the korean Society of Automotive Engineers
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• v.11 no.3
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• pp.8-12
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• 1989

The development of a microprocessor-controlled centreless grinding station has opened the way for the production of automobile camshafts-from raw casting to precision-finished part-as a fully automated operation. This results in manufacture to finer tolerances, with part-to-part consistency and a floor-to-floor time of half that needed for alternative production methods. Shafts with a grinding length of up to 700 mm can be processed.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2000.04a
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• pp.441-446
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• 2000

Although the net-shape molding of composites is generally recommended, molded composites frequently required cutting or grinding due to the dimensional inaccuracy for precision machine elements. During the composite machining operations such as cutting and grinding, the temperature at the grinding area may increase beyond the allowed limit due to the low thermal conductivity of composites, which might degrade the matrix of composite. Therefore, in this work, the temperature at the grinding point during surface grinding of carbon fiber epoxy composite was measured. The grinding temperature and surface roughness were also measured to investigate the surface grinding characteristics of the composited. The experiments were performed both under dry and wet grinding conditions with respect to cutting speed, feed speed, depth of cut and stacking angle. From the experimental investigation, the optimal conditions for the composite plain grinding were suggested.

• Journal of the Korean Society for Precision Engineering
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• v.24 no.6
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• pp.51-57
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• 2007

Creep-feed grinding is an effective technology processes to increase the productivity and efficiency in form grinding. This method has, however, some problems which the progress of abrasive wear around the cutting edge is remarkable, grinding force become intense and burn marks on the ground surface occur frequently. In order to solve this problems, it is proposed in this study to dress the grinding wheel continuously during the grinding process. The purpose of this research is. therefore, that CNC creep-feed grinding machine which has a continuous dressing device developed and some grinding experiments for determination of dressing conditions carried out.

• Journal of the Korean Society for Precision Engineering
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• v.17 no.4
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• pp.173-180
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• 2000

In the process of grinding a long slender type workpiece, such as ballscrew, by the external cylindrical grinding machine, the cylindricity of the workpiece depends on the distance of rests, the stiffness of supports, the diameter and material of workpiece. Conventionally the process needs to be supported by one or more rests to prevent static deflection and vibration. In this paper, the optimal position of the rests was investigated in order to minimize the cylindricity due to the static deflection, by taking compliance of the workpiece and structure into account. In order to obtain the optimal position of rests, a new modeling that is considering the spring effect of all support elements was established. Since it is so complicated to obtain the optimal position analytically for various conditions due to discontinuity, a genetic algorithm u as utilized.

• 한국기계연구소 소보
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• s.17
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• pp.23-28
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• 1987

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 2001.04a
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• pp.309-314
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• 2001

The balance of high speed spindle system with high precision rotation like grinding machine is very important. Traditionally, we use trial and error method to balance the spindle. It takes much time. So we are developing the automatic balancing equipment being used in the grinding machine. The balancing head we develop is wireless. It will be used high-speed grinding machine. We use influence coefficient method to control the automatic balancer. Experiments are based on automatic and manual balancing. We perform test of the vibration filter. It helps to remove noise. The filter and experiments with automatic balancing controller show that automatic balancing control can be successfully achieved with the quick response and good stability characteristics.