Most suspension systems attach the shock to a moving linkage at the top, and a fixed frame mount on the bottom.
大多数避震系统将减震器上端连接在一个可移动的部件，下部则连接在固定的车架部分上。
2
The tower type belt driven long stroke pumping unit is composed of the crank-linkage-slide mechanism, movable pulley-narrow belt-fixed pulley mechanism and compound drum stroke-increment mechanism.