Fumio Murakami

Automatic Control of Woolen Card

目的光電管によってウエブ厚みを測定し, その測定値に応じてドッファを変速する方法で紡毛カードの紡出粗糸の太さを自動制御する系について, アナログコンピュータおよびアナログ相関機を用いて制御工学的に解析を行なう.成果1. 紡毛カードのドッファ速度変化%とウエブ厚み変化%に関する動特性はつぎの伝達関数であらわされる.Gp (s) =-e-12S/1+12S (時間単位sec)2. ウエブ厚みの測定に際して生ずる検出ノイズは無視しえない程度に大きく, 制御成績に相当な影響をおよぼすことがわかった.したがって統計的手法による解析が有効な手段となる.3. 自動制御を行なうことによって約100m以上の波長の粗糸むらを減少することができる.粗糸64本の連続2mカット試料の量目変化の標準偏差は, 自動制御を行なうことによってσ=2%の程度までは減少しうることが実験的にわかり, またこのことは理論的にもたしかめられた.

Continuous Control of Sliver Thickness

This is an attempt to approximate the characteristics of two major types of servo-draft systems the open-loop system and the closed-loop system-by comparatively simple mathematical models consisting of linear transfer functions. The effectiveness of servo-draft systems in terms of the frequency response of the mathematical models has been investigated with the following results: (1) Sinusoidal variations in input sliver thickness cannot be effectively attenuated by the servo-draft system if the frequency of such variations exceeds a certain limit. This limit frequency is fixed by the time constants of the system components. (2) The open-loop servo-draft system is much higher in limit frequency than the closed-loop system if their time constants are equal. In other words, the open-loop system can attenuate sliver irregularities of higher frequencies than the closed-loop system can. (3) In most servo-draft systems there are frequency ranges in which the normalized amplitude of input thickness variations is magnified, rather than attenuated. (4) The open-loop and closed-loop systems can be combined Into one servo-draft system to make use of the advantages of the two systems. The characteristics of such a combined system are easily predictable from the characteristics of the two constituent systems.