六、挂车各主要部件的结构型式(一)车架车架是整个挂车的基础,它承受着各种力和力矩。在重型挂车上,车架和货台往往做成一体,要求有足够的强度和刚度,又要轻便。挂车的车架通常采用型钢或M_n钢板拼焊结构,其断面见图6—2所示,多为工字形。车架的纵梁结构形式有直梁式、阶梯梁式和四梁式三种(见图6—1)。 Sixth, the structure of the main components of the trailer (a) frame The entire trailer frame is the foundation, it is subjected to a variety of forces and moments. In heavy-duty trailers, the frame and the dock are often made in one, require adequate strength and stiffness, but also lightweight. Trailer frame usually welded steel or M_n plate structure, the cross-section shown in Figure 6-2, mostly I-shaped. Frame structure of the vertical beam beam, step beam and four beam three (see Figure 6-1).