可調注射式磁黏滯阻尼器之設計開發

Abstract

應用磁黏滯液體(Magnetorheological fluid，MR Fluid)設計模組化的可調注射式磁黏滯阻尼器。以分流的方式與一般黏滯液體阻尼器整合為減振系統，由改變外部驅動電流產生磁場變化及調節節流道截面積大小來控制阻尼特性，達到半主動式控制之即時調整減振效果。 以旋入式的導磁調節棒控制節流道截面積，磁迴路通過調節棒使節流道為磁黏滯液體產生黏度變化的工作區。並透過理論計算與電腦輔助程式模擬分析驅動電流產生的磁場通過磁迴路磁黏滯液體之影響。 使用伺服馬達以及滾珠螺桿推動線性平台作為實驗設備來測試設計之阻尼器，測試項目包括位移、受力、速度等。可得知當流道間隙變小以及提高驅動電流使磁黏滯液體受磁場影響改變黏度均可使阻尼力上升。設計開發之可調注射式磁黏滯阻尼器可作用的最大阻尼力在作動頻率1 Hz、位移 ±4 mm、流道間隙dmr = 1 mm及驅動電流I = 0.5 A時為301.3 N。比較最小阻尼力，作動頻率0.25 Hz、位移 ±2 mm、流道間隙dmr = 5 mm及無驅動電流時，產生的阻尼力為153.2 N，阻尼力變化率為1.97。

Magnetorheological fluid (MR fluid) is applied to design the modular syringe-type MR fluid damper, which is integrated with normal viscous liquid into absorption of vibration system by bypass method. Characteristic of damper can be controlled by varying the external drive current to change the magnetic field and adjusting the cross-sectional area of throttle valve, and semi-active style absorption of vibration with real-time adjustment can be achieved. The screwing magnetic adjustment rod is used to control the cross-sectional area of throttle valve. Magnet circuit passes through the adjustment rod that makes throttle valve become the viscosity varying area of viscous liquid. Theory calculation and Maxwell software are applied to simulate and analyze the influence of viscous liquid, while the magnetic field generated by drive current passing through the magnet circuit. Using servo motor and ball screw to test the designed damper, including displacement, state of stress and velocity. According to the measurement, the viscosity of viscous liquid will change with the effect of magnetic field while decreasing path gap or increasing drive current, and the damping force can be enhanced. The biggest damping force of designed syringe-type MR fluid damper is 301.3 N while path gap dmr is 1 mm, drive current I is 0.5 A, frequency is 1 Hz and displacement is ±2 mm. And while path gap dmr is 5 mm, displacement is ±2 mm, frequency is 0.25 Hz and no drive current, the smallest damping force is 153.2 N, and the ratio of damping force is 1.97.