The piston may be connected to the upper end of the connectingrod either directly (trunk piston type), or indirectly (crosshead type).
活塞与连杆上端的连接，既可以是直接连接(筒状活塞式)，也可以是间接连接(十字头式)。
2
In trunk-piston engines, a horizontal pin within the piston is encircled by the upper end of the connectingrod. This by far the most common construction.
在筒状活塞式的发动机中，活塞与连杆上端通过一个水平销子连接。这是最常见的一种结构。
3
The transition pedal mechanism comprises a transition pedal, a gas spring, a cross rod, a connectingrod, and an upper and a lower sleeves of a movable rod.