A spacing piece is arranged at the portion close to the back of the installation rod, and the outer edge of the spacing piece leans against the chassis outside the through-hole. 在安装条上靠近后端的部位设置限位片,该限位片的外边缘倚靠在通孔外的底座上。
Thin space: A type spacing piece equal to one-fifth of an em. 薄空铅:相等于正方五分之一的活字间隔材料。