• 한국정밀공학회지
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• 제19권12호
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• pp.109-119
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• 2002

In this paper, mechanism design of optical pickup actuator for fast access is proposed. This actuator is composed of moving magnet type actuator and moving coil type actuator for tracking and fine motion, respectively. Moving magnet type tracking actuator is configurated by two permanent magnets and four air-core solenoids. Additional damper by induced current in tracking actuator can reduce the transient vibration between the coarse seeking servo and fine seeking servo. Variable stiffness can be acquired by applying current to air-core solenoid simply. This actuator can achieve fast access by these additional damper and stiffness. Performance of this actuator is predicted through the FEM, simulation and simple experiment. Settling time for transient vibration is reduced to 14.7% according to simulation result.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 B
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• pp.857-859
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• 2002

This paper describes an analysis of Magnetic actuator with permanent magnet using 2-D axisymmetric finite element method. Magnetic actuator is the machine to change electrical signal into mechanical signal, and fast switching device to be used for breaker and automation field etc. This magnetic actuator considered action for armature distance, external circuit, and nonlinear material characteristic and current. Also, comparative analysis is performed for 2 coil type and 1 coil type by coil type of actuator, then characteristic is grasped. It is Combined with external circuit for analyzing transient characteristic by variable time. According to the results, we analyzed action characteristic of Magnetic actuator.

• Journal of Electrical Engineering and Technology
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• 제7권3호
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• pp.342-348
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• 2012

This paper presents a moving-magnet type linear actuator designed by using flux concentration type permanent magnet arrangement, which can generate higher magnetic flux density in air-gap. In this construction, detent force which is induced by both slot-effect and end-effect becomes larger due to strong attractive forces. To reduce cogging force we have employed a modular mover structure of two magnetic pole sections connected with a center yoke. The improved motor performance is demonstrated with the prototype machine.

• 대한기계학회논문집A
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• 제37권3호
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• pp.359-364
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• 2013

직선형 진동모터가 휴대전화의 알림용이나 햅틱 인터페이스의 구동기로 적용되려면 빠른 응답속도와 긴 수명을 제공하여야 한다. 본 논문에서는 기존 직선형 진동모터를 개선하여 보이스 코일 구동기와 영구자석 스프링을 이용한 직선형 진동모터를 제시하고, 설계 제작하여 그 가능성을 검증하였다. Halbach 배열의 영구자석에 의해 구동되는 보이스 코일 구동기와 영구자석 간의 반발력을 이용하는 영구자석 스프링을 해석하고 설계하기 위해, 등가전류판 방법과 이미지 방법을 사용하였고, 방법의 적절성을 유한요소해석을 통해 검증하였다. 시작품 모터를 설계하고 제작하고, 실험을 통해 진동모터의 특성을 확인하였다.

• 한국신뢰성학회지:신뢰성응용연구
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• 제14권3호
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• pp.147-151
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• 2014

An actuator latch device of a hard disk drive is installed for locking an actuator to hold a magnetic head parked in a parking zone. Applying an external force to the drive, the head can move away from the parking zone and destroy data on the disk. A magnet latching mechanism is used to prevent the actuator from moving when the computer is not in use. A permanent magnet holds the actuator when the head is in the parking zone. When the computer is turned on, the actuator has to overcome the latch magnet in order to move. A stronger latch magnet will hold the actuator adequately, but the actuator will not be released when unlocking is required. A breakthrough solution is needed to improve the reliability of the drive without any deterioration of its performance. In order to obtain the idea for resolving this technical contradiction, we analyse patents for actuator latch device of a hard disk drive. A practical way for solving contradictions in product development using TRIZ is proposed in this paper.

• International Journal of Control, Automation, and Systems
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• 제2권3호
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• pp.279-288
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• 2004

This paper presents a novel design for a tubular linear brushless permanent-magnet motor. In this design, the magnets in the moving part are oriented in an NS-NS―SN-SN fashion which leads to higher magnetic force near the like-pole region. An analytical methodology to calculate the motor force and to size the actuator was developed. The linear motor is operated in conjunction with a position sensor, three power amplifiers, and a controller to form a complete solution for controlled precision actuation. Real-time digital controllers enhanced the dynamic performance of the motor, and gain scheduling reduced the effects of a nonlinear dead band. In its current state, the motor has a rise time of 30 ms, a settling time of 60 ms, and 25% overshoot to a 5-mm step command. The motor has a maximum speed of 1.5 m/s and acceleration up to 10 g. It has a 10-cm travel range and 26-N maximum pull-out force. The compact size of the motor suggests it could be used in robotic applications requiring moderate force and precision, such as robotic-gripper positioning or actuation. The moving part of the motor can extend significantly beyond its fixed support base. This reaching ability makes it useful in applications requiring a small, direct-drive actuator, which is required to extend into a spatially constrained environment.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 하계학술대회 논문집 B
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• pp.813-815
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• 2003

In this study, two magnetic actuator models are chosen to interpret dynamic characteristics. First model has no permanent magnet, on the contrary second has magnet that hold plunger to keep steady state. Both models are dynamically analyzed according to input current, and also compared with spending time and magnetic force at that moving is finished.

• 한국자기학회지
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• 제20권1호
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• pp.28-33
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• 2010

리니어 펌프 구동용 하이브리드 전자기 리니어 엑츄에이터를 해석하고 설계하였다. 솔레노이드 엑츄에이터는 기계적인 에너지 변환장치가 필요하지 않기 때문에 공간을 많이 차지하지 않는 이점으로 인해 널리 사용되고 있다. 또한 에너지 손실이 매우 낮고 소음이 발생하지 않는 장점을 가지고 있다. 하지만, 솔레노이드 엑츄에이터는 전력소비가 크다는 단점을 가지고 있다. 이런 단점을 보완하여 전력소비를 줄이기 위하여 영구자석을 활용한 새로운 하이브리드 전자기 리니어 엑츄에이터를 제안하고 향상된 성능을 검증하기 위해 동적 유한요소 분석을 통해 시뮬레이션을 수행하였다.

• Journal of international Conference on Electrical Machines and Systems
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• 제1권4호
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• pp.517-524
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• 2012

The operation of linear oscillating system is complicated, involving system nonlinearities of both actuator and load, and variations of driving frequency in order to track the mechanical resonance. In this paper, both analytical and state-variable modeling techniques are used to investigate the influence of actuator parameters, such as back-emf/thrust force coefficient and cogging force, on the performance of linear oscillating systems. Analytical derivations are validated by simulations, and good agreements are achieved. The findings of the paper can greatly facilitate the design and evaluation processes of permanent magnet linear actuators.

• 한국정밀공학회지
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• 제25권9호
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• pp.53-58
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• 2008

The traditional engine valve train in a combustion engine is the mechanically driven camshaft system that provides one-fixed valve timing. The variable valve timing (VVT), however, is highly required to achieve the significant improvement in fuel economy. To achieve VVT in combustion engine, the solenoid type of actuator had been developed in past years, but it requires current in all operation period, the starting is difficult and the efficiency is low. In this paper, a new linear actuator using permanent magnet (PM) is proposed and verified its feasibility by finite element (FE) analysis.