摘要 |
The piston pin for a piston of an internal combustion engine is provided with a certain number of passages, each opening into the annular groove of the bearing bushing of the connecting-rod small end and into either of the annular grooves of the pin bearings. The passages are provided in a peripheral portion of the piston pin so to avoid a central portion of the pin, in which a concentration of metallic impurities is maximum. |