Sand core structure of engine body and engine body structure made of sand core

The invention discloses an engine body sand core structure and an engine body structure made of the sand core. A truss core head structure with bottom inserting, middle reversing and top pressing and an assembling technology are adopted. And the long and narrow truss core can be accurately and stably fixed on the main body core in a standing state. The long and narrow truss sand core is accurately and stably assembled on the main body sand core through constraint of six directions at the upper position, the middle position and the lower position, so that the truss core can turn over by 360 degrees along with the main body core and does not fall off after long-distance turnover. 本发明公开了一种发动机机体砂芯结构及由该砂芯制作的机体结构；采用底部插接、中部倒扣、顶部压装的桁架芯芯头结构和组装工艺。可以将狭长的桁架芯准确稳定的固定在处于站立状态在主体芯上。上中下三处位置6个方向的约束，将狭长的桁架砂芯准确稳定地组装在主体砂芯上，使得桁架芯可以随着主体芯360度翻转、长距离周转不掉落。