• 한국정밀공학회지
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• 제15권12호
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• pp.48-54
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• 1998

In sewing, fabrics is fed by an elliptic motion of the feed dog. The feeding control mechanism controls an elliptic motion of the feed dog, finally, controls stitch spacings and feeding directions of fabrics. This study discusses the feeding control mechanism of an industrial lock stitch sewing machine, which is a good example to study a machine kinematics. This study makes mathematical expressions of machine's motion in the feeding control mechanism. Thus, the motions of this mechanism are characterized, which will be used for kinematic analysis of the feed dog later. Also, the above mathematical expressions may be a basis for the new design of the feeding control mechanism and may be applied to development of the similar feeding control mechanism of other type sewing machine.

• 한국정밀공학회지
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• 제15권12호
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• pp.37-47
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• 1998

This study discusses the feed dog feeding mechanism of an industrial lock stitch sewing machine, which is a good example to study a machine kinematics. The feed dog feeding mechanism makes the fabrics directly be fed by an elliptic motion of the feed dog that is moved by a rotation of the top shaft and controlled by the feeding control mechanism. This study makes mathematical expressions of machine's motion in the feed dog feeding mechanism. Thus, the motions of this mechanism are characterized, namely how an elliptic motion of the feed dog is affected by the feeding control mechanism. Therefore, the above mathematical expressions may be a basis for the new design of the feed dog feeding mechanism and may be adapted to analysis. Development of the similar feed dog feeding mechanism can be applied to other type sewing machine.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1987년도 한국자동제어학술회의논문집; 한국과학기술대학, 충남; 16-17 Oct. 1987
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• pp.264-268
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• 1987

This paper is concerned on kinematic analysis and simulation of an automatic feeding mechanism subjected by the motion of a curvilinear inverse can. The curvilinear cam is rotated by positioning a translating roller and the automatic feeding mechanism is moved to the sliding position by the motion of a campin fixed on the curvilinear cam. The curvilinear cam consists of two arcs of circles and two straight lines. The modular approach is used for the kinematic analysis of the feeding mechanism. As the first part of the paper for the motion simulation of the cam-feeding system, this paper discusses the algorithm to simulate the motion of the cam-feeding mechanism. The second part of the paper presents the state-of-art for the graphics-oriented CAD technique,

• 한국생산제조학회지
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• 제19권5호
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• pp.596-602
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• 2010

In this study, a fmite element model was developed for analysis of feeding a structure in open loop control The finite element analysis (FEA) can simulate dynamic behavior of the structure of a machine tool rapidly traveling with a screw feeding driving system. The feeding mechanism was implemented with screw element of the FEA tool used in this study. The procedure was developed for the dynamic transient FEA. First, motion parameters such as jerk and velocity were introduced for the structure to be fed in open loop control When its traveling distance was determined, set-points for the distance were generated based on the motion parameters. The set-points were applied to the FE model constructed for the traveling structure. The FEA was executed and evaluated. In this study, the FEA procedure was applied to the column of a machine tool and the dynamic behavior of the column was evaluated. The FEA helps in evaluation of the motion characteristics of a structure. The convergence time of the structure vibration posterior to feeding termination can be estimated and the stiffness of the flexible structure is also evaluated against jerk, and acceleration. It provides the feeding force which is helpful in selection of the feeding motor.

• 반도체디스플레이기술학회지
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• 제2권2호
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• pp.21-24
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• 2003

Seam seal welding on the semiconductor package is a process for sealing the packages of semi-conductors, crystal parts, saw filters and oscillators with lid plate by seam welding. This paper presents the development process of automatic seam seal welding system. In this process, the process algorithm, high precision welding current control, design of welding head, high speed and high precision feeding mechanism and user interface process control program technologies are included.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1987년도 한국자동제어학술회의논문집; 한국과학기술대학, 충남; 16-17 Oct. 1987
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• pp.269-272
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• 1987

This paper is concerned on kinematic analysis and simulation of an automatic feeding mechanism subjected by the motion of a curvilinear inverse cam. The main objection is the development of computer-aided design (CAD) program for simulating the motion of the cam-feeding mechanism using computer-graphics. A computer program CACAFS (Computer-Aided Cam and Automatic Feeding System) is independent of computer hardware used. The program is also interactive using a menu-selection technique. As the second part of the paper for the motion simulation of the cam-feeding system, this paper discusses the state-of-art for CAD. The first part of the paper presents the algorithm to simulate the notion of the cam-feeding mechanism.

• 수면정신생리
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• 제5권1호
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• pp.34-44
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• 1998

Living organisms are influenced by many external rhythms and they have adapted their physiology to periodically changing conditions. These adaptive strategies are controlled by endogenous innate programs of behavior and physiology which are determined by external signals ("Zeitgeber"). There are many biological rhythms, each with its own characteristic functional adaptation. Among them, the presence of endogenous time control of feeding and drinking becomes obvious. There are increasing evidences that the control of food intake, food selection, and drinking are regulated by the endogenous rhythms including a circadian rhythm. However, there have been many restrictions in understanding the endogenous control of food intake itself and its mechanism. To broaden our know ledges of the endogenous time control of feeding and drinking, the author reviwed the characteristics of the endogenous timing for food intake, the influence of circadian pacemakers and food-entrainable oscillators, the interaction between the circadian control and the external and internal conditions in the control of food intake, the conseqences of feeding, the circadian control of food selection, and the biological cycles in energy balance.

• 한국생산제조학회지
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• 제20권6호
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• pp.685-691
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• 2011

The Bearing preload units are used for stable rotational movements of high speed spindles. The feeding mechanism of the preload unit is important to prevent overheat of bearings and to keep constant bearing load under thermal deformation of spindle unit. In this study, ball slide guide and ball bush as feeding mechanism of preload unit are selected. The maximum static friction force, radial stiffness and damping ratio of ball slide guide with ball load, ball number and ball size are widely investigated. In conclusion, the surface of ball slide guide must be heat treated to reduce static friction force. The number and size of ball are increased to control sensitive bearing preload force.

• 한국산학기술학회논문지
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• 제8권6호
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• pp.1381-1387
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• 2007

현재까지 다양한 연속적인 공정시스템은 섬유, 제지 및 인쇄 등 많은 산업응용 분야에서 사용되고 있다. 이러한 응용분야에서 공정처리를 받고 있는 제품에 가해지는 장력은 원료의 공급속도와 생산되는 제품의 방출 속도간의 속도차에 의해 변화될 수 있다 특히, 섬유공정에서 공급속도와 방출 속도간의 속도차나 관성효과에 의해 발생되는 장력변동은 제품의 품질을 저하시킬 수 있다. 따라서 섬유공정에서 이러한 요인들에 의해 발생되는 장력 변동을 적절한 방법에 의해 보상하는 것은 매우 중요한 문제이다. 본 논문에서는 이러한 문제를 해결하기 위하여 섬유공정에서 많이 사용되고 있는 환편기 시스템에서의 장력제어 문제를 다루고자 한다. 먼저 일반적인 연속공정의 권취 메커니즘에 대한 장력 관계식을 모델링한다. 다음은 환편기 시스템에서 풀림롤과 감김롤을 효율적으로 구동하기 위하여 풀림롤과 감김롤간의 속도차와 관성특성을 고려한 새로운 장력제어 방법을 제시한다. 다양한 실험을 통하여 제안된 장력제어 방법이 주어진 환편기 시스템의 공정구간에서의 장력제어 성능을 향상시킬 수 있음을 보인다.

• 한국공작기계학회논문집
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• 제16권2호
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• pp.50-56
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• 2007

Wire forming machine is widely used in industries to make a variety of wire products such as coil springs and links. Along with the rapid development of CNC technologies, the usage of wire forming machine varies from single-purpose machinery to universal CNC machinery. Rotating the wires while feeding them simultaneously, we can improve the performance of the machines with aspects of efficient tooling and complicated geometric forming. In this study, a new gear train is developed for the control of both feeding and rotating wires independently at the same time. The developed mechanism has many benefits as following, making more complicated geometric and precision products, easier tooling, and simpler programming.