• 한국자동차공학회논문집
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• 제21권5호
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• pp.74-81
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• 2013

The high-speed machining in the manufacturing industry field has been widely applied for parts of vehicles, aircraft, ships, electronics, etc., recently, because the effect of cost savings for shortening processing time and improving productivity is great. The purpose in this study is to investigate the effect of cutting depth on the surface roughness of workpiece with the spindle rotational speed and feed rate of high-speed machines as a parameter to find the optimal depth in the finishing for ball end mill of the aluminum alloy 7075 which is used much in aircraft parts. When the cutting depth for the respective feed rate and spindle rotational speed is varied from 0.1 mm to 0.7 mm at intervals of 0.2 mm in the wet finishing of the aluminum alloy 7075 by the insoluble cutting oils and high-speed machining used in the rough machining of previous study, the surface roughness values and the cutting temperature are measured. In addition, the cutting surface shapes of test specimens are observed by optical microscope and compared with respectively. It is found that the surface roughness values and the temperature generated during machining are increased as the feed rate and cutting depth are raised, but those are decreased as the spindle rotational speed is increased.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1995년도 추계학술대회 논문집
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• pp.985-990
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• 1995

Recently, the development of high speed and high precision NC-lathe for piston head machining is needed for the complexity and diversity of the piston head shape used in automobile reciprocating engine. THe piston head has many complex shapes in the aspect of fuel economy, such as ovality, profile, double ovality and recess. Among them, for the maching of the over shape of 0.1~1mm the cutting tool should move periodically symchronized with the rotation of piston workpiece. The cutting tool feeed system must have high positioning accuracy for the precise machining, high speed for the fast maching and high dynamic stiffness for the cutting force. The linear brushless DC motor is used for satisfying these coditions. The ballbush guide and supporting guide using turcite is used for the guidance of the feed drive system. Linear encoder, digital servo ampllifer and controller are used for driving the motor. THis paper presents the design and simulation of the new tool feed system for noncircular machining.

• 한국정밀공학회지
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• 제26권1호
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• pp.138-145
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• 2009

High-efficiency and high-quality machining has become a fact of life for numerous machine shops in recent years. And high-efficiency machining is the most significant tool to enhance productivity. In this study, to achieve high-efficiency machining in turning process, a spindle speed optimization method was proposed based on a cutting power model. The cutting force and power were estimated from the cutting parameters such as specific cutting force, feed, depth of cut, and spindle speed. The time delay due to the acceleration or deceleration of spindle was considered to predict a more accurate machining time. Especially, the good agreement between the predicted and measured cutting forces showed the reliability of the proposed optimization method, and the effectiveness of the proposed optimization method was demonstrated through the simulation results associated with the productivity enhancement in turning process

• 한국정밀공학회지
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• 제21권1호
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• pp.133-139
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• 2004

High speed machining (HSM) can reduce machining time with the high metal removal rate by high speed spindle and feedrate. This paper supports HSM technology using the small size tool with the optimal tool path generation and modification of tool change. The optimum tool path is generated to reduce cutting length of cavity pattern and change the cutting tool for preventing the tool breakage by wear. The tool path is modified with the experiment data of tool wear and breakage to support tool change on reasonable time. The result can contribute to HSM technology of high hardness materials using the small size end-mill.

• 청정기술
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• 제12권3호
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• pp.182-189
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• 2006

본 연구에서는 생산성 향상을 위하여 적용 분야가 점차로 확대되고 있는 고속 절삭가공의 경제성 및 환경비용을 평가하였다. 가공시간 및 가공비용이라는 절삭공정의 경제성 평가 모델과 더불어 수학적으로 모델링 된 절삭유제의 손실량 및 폐 유제 처리비용을 이용하여 환경비용을 고려한 절삭공정의 생산비용을 분석하였다. 분석에는 CBN 볼 엔드밀을 사용한 고속가공과 여러가지 냉각방식을 적용한 고속 선삭가공 공종에 대한 공수수명 및 공구마모 실험 데이터를 이용하였다. 고속 밀링가공에서 절삭속도가 높을수록 생산비용은 작아져서 고속가공의 장점을 그래도 보여주었다. 압축공기, 냉풍, 수용성 절삭유제, 건식 절삭의 네 가지 냉각방법을 사용한 선삭가공의 분석에서는 절삭유제를 이용한 냉각방식이 절삭유제를 사용하지 않은 방식에 비하여 공수수명의 향상으로 생산비용이 작았으나 환경비용을 고려하면 냉풍을 이용한 냉각방식이 생산성과 환경영향의 모든 면에서 가장 우수하였다.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 1995년도 추계학술대회 논문집
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• pp.139-142
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• 1995

Inconel 718 is one of the most difficut workpiece for machining, So it is necessary to evaluate the machining characteristics of Inconel 718 In this study, High speed machining of this material was carried out with Tin coated WC ball endmill and TiN coated HSS ball endmill. The cutting force and shape of machined surface and cip type were investigated according to variation of cutting speed,feed rate and depth of cut

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 춘계학술대회 논문집
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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.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2000년도 Handout for 2000 Inter. Machine Tool Technical Seminar
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• pp.29-33
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• 2000

OKUMA Die/Mold manufacturing system provides high speed, high rigidity and heavy cutting in a compact machining center and CAD/CAM system.

• 한국기계가공학회지
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• 제1권1호
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• pp.38-47
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• 2002

Machining quality has been improved with the development of cutting tools. However, it is difficult to obtain a high degree of quality in machining a deep pocket with a long end mill, since machining accuracy is mainly dependent on the stiffness of the cutting tool and tool holder. To improve machining quality in machining a deep pocket using an end mill, the performance by cutting condition compare with others. Owing to this problem, it is necessary to select suitable tool and holder in the deep pocket machining. In this study, the hydraulic holder for the high speed machining is introduced and the performance of that is compared with others according to cutting conditions. The cutting parameters involved were; slenderness ratio in the range of 3 to 6 (L/D), radial depth of cut from 0.01 to 0.05 mm. Cutting force and surface roughness, precision of form were observed during the experiment to investigate cutting state.

• 한국산학기술학회논문지
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• 제15권2호
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• pp.603-608
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• 2014

항공기와 자동차 부품과 관련된 많은 제조업에서, 낮은 비중과 높은 강도에서 뛰어난 알루미늄 합금(Al2024)은 효과적으로 사용되었다. 가공소재의 표면거칠기 품위를 위한 정면밀링 가공기술은 이들 분야에서 적용되어 왔다. 챔퍼된 드로우 어웨이 타입의 인서트를 갖는 정면밀링 가공은 단지 이론적으로 완전한 평면을 생산할 수 있다. 그러나 그것은 절삭온도, 소성변형, 동적효과 등으로 인하여 불가능하다. 본 논문에서 실험적 연구는 검증된 고속가공이 가능한 정면밀링커터 바디를 사용하여 Al2024의 고속가공 후 표면거칠기를 개선하기 위하여 수행되었다.