8·1 四冲程发动机的设计步骤设计发动机的第一步是根据使用目的选择最合适的类型,如汽油机或柴油机、水冷或风冷,四冲程或二冲程等。类型确定之后,再根据所需功率(轴马力)决定恰当的发动机转速,压缩比、缸径、活塞行程以及配气机构的型式等,然后再确定参数。设计发动机时,大都参考类似的实际例子,从制定方案图入手同时进行强度计算,在确 8.1 Design Procedures for a Four-Cycle Engine The first step in designing an engine is to choose the most suitable type for your application, such as a gasoline or diesel engine, water or air cooling, four-stroke or two-stroke, and so on. Once the type has been determined, determine the appropriate engine speed, compression ratio, bore size, piston travel, and valve train type based on the required power (shaft horsepower), and then determine the parameters. When designing an engine, most of them refer to similar practical examples, starting with formulating a plan and calculating the intensity at the same time.