结构皮带变速器主要是由两片定轮与中间的动轮所组成,图1是速比1:1时的状态。旋转摇手柄(?)后,滑块4沿丝杠6轴向移动,带动轮组一起移动,使轮组上的上下两轮直径改变,从而达到变速的目的。两片定轮3的相对位置是不变的,中间动轮2的轴孔是动配合,可自由地在两片定轮之间滑动.当轮组向左上方移动时(见,图1左图),变速器的中心线向左移,动轮受两条皮带的限制成为图 Structure Belt transmission is mainly composed of two fixed wheels and the middle of the moving wheel formed, Figure 1 is the ratio of 1: 1 state. After rotating the handle (?), The slider 4 moves along the axial direction of the screw 6 to drive the wheel set to move together to change the diameters of the upper and lower wheels of the wheel set so as to achieve the purpose of speed changing. The relative positions of the two fixed wheels 3 are unchanged, and the shaft hole of the middle movable wheel 2 is a dynamic fit and can slide freely between the two fixed wheels. When the wheelset moves to the upper left (see the left picture in FIG. 1 ), The centerline of the transmission is shifted to the left, and the running wheels are restricted by the two belts