• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.10a
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• pp.57-57
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• 2003

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.6
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• pp.1121-1140
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• 1992

In metal cutting the shape of generated chip varies according to cutting conditions, characteristics of workpiece and geometry of cutting tool. The best surface roughness of machined workpiece is obtained when generating flow type contrinuous chip. If the generated chip is not broken, that is not only tangled workpiece and cutting tool, but also may give damage on the machined surface of workpiece or danger for a operator. The flow type continuous chip may bring the low productivity in high speed any heavy cutting, automatic machining process and non-human factory. There are two type of chip break process ; controlling cutting condition and using chip breaker. In present study we carried out the experiment on new type chip breaker compared with conventional type and proved the efficiency of a new type and showed the chip break condition to be applied in actual metal cutting. In the experiment SM 20 C as a workpiece material and WC as a tool material were used and cutting speed of 30-150m/min, feed of 0.071-0.210mm/rev and depth of cut of 1mm were applied as cutting condition. The results of the experiment are as follows : (1) The mechanism of chip curl can be explained more clearly by plastic flow of workpiece material and moment of shearing force. (2) The most effective radius of curled chip and flat distance from cutting edge is 2.0-2.5mm and 1.5mm in both types. (3) The effective inclination angle of chip break surface and side cutting edge angle are 30.deg.- 45.deg. and 20.deg. in conventional type, while the radius of arc surface, lower arc angle A, upper arc angle B and side cutting edge angle are 3mm, 20.deg.- 45.deg., 0.deg.- 45.deg. and 10.deg.- 20.deg. in new type. (4) The probability to be obtained 100% chip breaking ratio is much higher in new type than in conventional type.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.493-494
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• 2006

Chip breaker of cutting tool is an important feature to enhance cutting performance. Powder injection molding process was used to produce a triangular-shape cermet grooving insert which has three chip breakers. Attrition milled cermet powders were mixed with wax-based binder system in continuous twin screw extruder. Three-plate injection mold with slide cores was used to produce injection-molded parts. After molding, solvent and thermal debinding was carried out. Sintering was conducted in a batch furnace with a graphite heater. The sintered parts satisfy the requirements of dimensional tolerances and material properties.

• Transactions of the Korean Society of Mechanical Engineers
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• v.11 no.6
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• pp.1005-1013
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• 1987

For the factory automation and unmanned machine operation, it is very important to manufacture highly reliable and efficient chip breakers for optimal chip control. In this research, using the CALMA CAD/CAM SYSTEM, the manufacturing process of 3-dimensional chip breakers is established. Using the results of the cutting test of the selected chip breakers with double-step grooves, the chip breaking mechanism is schematically analysed. An expression for the chip breaking relation is derived which considers chip material behavior following LUDWIK's stress-strain curve, chip breaking criterion and the shape of chip breakers. This contains the thickness of chip, the radius of chip curl, and the mechanical properties of chip materials. It is found that the expression agrees very closely with the experimental results.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.9 no.2
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• pp.96-101
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• 2000

In machining with cutting tool inserts having complex chip groove shape the flow curl and breaking pattern of the chip are different than in flat-face inserts. In the present work an effort is made to understand the three basic phe-nomena occurring in a chip since its formation in machining with groove type and pattern type inserts. These are the ini-tial chip flow the subsequent development of up and side curl and the final chip breaking due to the development of tor-sional and bending stresses. in this paper chip flow angle in a groove type and pattern type inserts. The expres-sion for chip flow angle in groove type and pattern type inserts is also verified experimentally using high speed filming techniques.

• Proceedings of the Korean Society of Machine Tool Engineers Conference
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• 1999.10a
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• pp.381-386
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• 1999

In machining with cutting tool inserts having complex chip groove shape, the flow, curl and breaking patterns of the chip are different than in flat-face type inserts. In the present work, an effort is made to understand the three basic phenomena occurring in a chip since its formation in machining with groove type and pattern type inserts. These are the initial chip flow, the subsequent development of up and side curl and the final chip breaking due to the development of torsional and banding stresses. In this paper, chip flow angle in a groove type and pattern type inserts. The expression for chip flow angle in groove type and pattern type insets is also verified experimentally using high speed filming techniques.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.11
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• pp.64-70
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• 2003

This paper suggests a systematic methodology to predict chip forms using the experimental design technique and the neural network. Significant factors determined with ANOVA analysis are used as input variables of the neural network back-propagation algorithm. It has been shown that cutting conditions and cutting tool shapes have distinct effects on the chip forms, so chip breaking. Cutting tools are represented using the Z-map method, which differs from existing methods using some chip breaker parameters. After training the neural network with selected input variables, chip forms are predicted and compared with original chip forms obtained from experiments under same input conditions, showing that chip forms are same at all conditions. To verify the suggested model, one tool not used in training the model is chosen and input to the model. Under various cutting conditions, predicted chip forms agree well with those obtained from cutting experiments. The suggested method could reduce the cost and time significantly in designing cutting tools as well as replacing the“trial-and-error”design method.

• Proceedings of the KAIS Fall Conference
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• 2006.05a
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• pp.112-115
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• 2006

본 논문에서는 무인 생산 공정의 선삭 가공 시 발행하는 칩의 처리에 관한 연구를 수행하였다. 선삭시 발생되는 칩은 부품의 정밀도와 표면 조도를 저하시키는 등 품질 저하와 함께 생산성을 저해하는 요소가 되기도 한다. 이러한 칩을, 칩 브레이커를 사용하여 작은 곡률 반경으로 절단함으로써 칩 제거를 효율적으로 제어한다. 그와 함께, 다구찌 기법을 적용하여 최적의 조건으로 칩 브레이커 형상 설계 인자를 도출하는데 그 목적이 있다.

• Proceedings of the IEEK Conference
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• summer
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• pp.61-65
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• 2004

An on-chip debugging unit is proposed aiming performance enhancement of JTAG-based SoC systems. The proposed unit comprises a JTAG module and a core breaker. The IEEE 1149.1 standard has been modified and applied to the new JTAG module. The proposed unit eliminates redundant clock cycles included in the TAP command execution stage reducing overall debugging time. TAP execution commands are repeatedly issued to perform debugging of complicated SoC systems. Simulation on the proposed unit shows some $14\%$ performance enhancement and $50\%$ gate count reduction compared to the conventional ones.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.30 no.3A
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• pp.226-232
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• 2005

An on-chip debugging unit is proposed aiming performance enhancement of JTAG-based SoC systems. The proposed unit comprises a JTAG module and a core breaker. The IEEE 1149.1 standard has been modified and applied to the new JTAG module. The proposed unit eliminates redundant clock cycles included in the TAP command execution stage. TAP execution commands are repeatedly issued to perform debugging of complicated SoC systems. Simulation on the proposed unit shows some 14% performance enhancement and 50% gate count reduction compared to the conventional ones.