一、设计概况交通运输业是国民经济的先行,随着四化建设的发展,广大用户对汽车的数量、品种和质量提出了新的要求。尤其是农村商品经济的迅速发展,农村市场的汽车需求量猛增。农村的各种动力机械都采用柴油为燃料。因此,柴油机汽车非常受农村用户的欢迎。同时柴油车具有优越的经济性。而目前国内生产的中吨位 First, the design overview Transportation is the forerunner of the national economy, with the four modernizations, the majority of users on the number of cars, varieties and quality put forward new requirements. Especially in the rapid development of rural commodity economy, the demand for automobiles in the rural market soared. A variety of power machinery in rural areas are using diesel fuel. Therefore, diesel vehicles are very popular with rural users. At the same time diesel has superior economy. The current domestic production of tonnage