First get the feeling of pivoting. 首先要獲得繞軸旋轉(zhuǎn)的感覺。
This short-arc coupled with the low pendulum effect achieved by pivoting the disc through a point near its center of gravity assures rapid closure. 繞軸旋轉(zhuǎn)的閥瓣的重力中心距軸心較短，因此這種短弧的鐘擺效應(yīng)也比較小，從而確保能夠迅速關(guān)閉。