• Title/Summary/Keyword: Micro-Machine

Search Result 736, Processing Time 0.032 seconds

Numerical Analysis and Experimental Study of Thread Rolling Process for Micro-sized Screws(Part II: Application to a Micro-screw with Diameter of 800㎛) (마이크로 체결부품 전조성형공정에 관한 해석 및 실험적 고찰(Part II: M0.8급 마이크로 스크류 전조공정 적용))

  • Song, J.H.;Lee, J.;Lee, H.J.;Lee, G.A.;Park, K.D.;Ra, S.W.;Lee, H.W.
    • Transactions of Materials Processing
    • /
    • v.21 no.3
    • /
    • pp.179-185
    • /
    • 2012

  • In this paper, it is proposed to produce high precision screws with a diameter of $800{\mu}m$ and a thread pitch of $200{\mu}m$ ($M0.8{\times}P0.2$) by means of a cold thread rolling process. In this part II of the study, the focus is on the production and reliability testing of the prototype $M0.8{\times}P0.2$ micro-screw. Designs for two flat dies were developed with the aid of the literature and previous studies. Process parameters during the cold thread rolling process were established through FE simulations. The simulation results showed that the threads of the micro-screw are completely formed through the rolling process. Prototype $M0.8{\times}P0.2$ micro-screw were fabricated with a high precision thread rolling machine. In order to verify the simulation results, the deformed shape and dimensions obtained from the experiment were compared with those from the simulations. Hardness and failure torque of the fabricated micro-screw were also measured. The values obtained indicate that the CAE based process design used in this paper is very appropriate for the thread rolling of micro-sized screws.

  • https://doi.org/10.5228/KSTP.2012.21.3.179 인용 PDF KSCI

Approximate Optimization of an Active Micro-Mixer (능동형 미소혼합기의 근사최적화)

  • Park, Jae-Yong;Kim, Sang-Rak;Yoo, Jin-Sik;Lim, Min-Gyu;Kim, Young-Dae;Han, Seog-Young;Maeng, Joo-Seung
    • Transactions of the Korean Society of Machine Tool Engineers
    • /
    • v.17 no.5
    • /
    • pp.95-100
    • /
    • 2008

  • An active micro-mixer, which is composed of an oscillating micro-stirrer in the micro-channel to provide effective mixing was optimized. The effects of molecular diffusion and disturbance by the stirrer were considered with regard to two types of mixer models: the simple straight micro-channel and micro-channel with an oscillating stirrer. Two types of mixer models were studied by analyzing mixing behaviors such as their interaction after the stirrer. The mixing was calculated by Lattice Boltzmann methods using the D2Q9 model. In this study, the time-averaged mixing index formula was used to estimate the mixing performance of time-dependent flow. The mixing indices of the two models were compared. From the results, it was found that the mixer with an oscillating stirrer was much more enhanced and stabilized. Therefore, an approximate optimization of an active micro-mixer with an oscillating stirrer was performed using Kriging method with OLHD(Optimal Latin Hypercube Design) in order to determine the optimal design variables. The design parameters were established as the frequency, the length and the angle of the stirrer. The optimal values were obtained as 1.0346, 0.66D and $\pm45^{\circ}$, respectively. It was found that the mixing index of the optimal design increased by 88.72% compared with that of the original design.

  • PDF KSCI

A study on flexible manufacturing system for engine cylinder block (엔진 실린더 블럭 가공라인의 자동화 시스템에 관한 연구)

  • 전용철;윤병용;홍동표
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 1986.10a
    • /
    • pp.544-546
    • /
    • 1986

  • In this report, we have designed a Flexible Manufacturing System(FMS) for Engine-Cylinder block that is composed of maching center, special purpose machine, AGV(Automatic Guided Vehicle), using Micro-Computer and Programmable Controller(PC). From this report, we mostly present hardware features and scheduling software.

  • PDF