| 摘要 |
PURPOSE:To permit connection of a cooling medium duct to a bearing with sufficient seal ensured and without need of providing the bearing with any extension by disposing the duct such that it assumes a position spaced apart from the axis of a piston shaft and extends in a direction tangential to a concentric circle passing through that position. CONSTITUTION:A cooling medium discharge path 11 which is formed inside a lower bearing 7 extends tangentially to an imaginary circle concentric with the axis O of a piston shaft 4 and having a radius L, so that its length can be increased compared to the conventional arrangement where the duct extends along a line passing through the axis. The path 11 is connected to a cooling medium duct 12, which is bent in V-shaped form at two points and is led out through a hole 13 formed in a casing 1 to the outside. Thus, the cooling medium duct 12 can be connected with a sufficient seal length secured and without providing the bearing with any extension. |
