Unit++转向系统.docVIP

Unit 12 Steering System第十二课 转向系统 12.1 Steering System Principles12.1 转向系统原理 The steering system is the means by which the driver of a vehicle is able to control the position of the front wheels. The system must provide case of handling, good directional control, and stability. This is achieved by the steering system in conjunction with the suspension. 驾驶员通过转向系统控制车辆前轮位置。这个系统要易于操纵，具有良好的方向控制性能和稳定性。这些是通过转向系统和悬架系统共同作用来实现的。 幻灯片9 For a car to turn smoothly, each wheel must follow a different circle. Since the inside wheel is following a circle with a smaller radius, it is actually making a tighter turn than the outside wheel. 为了使汽车能够平滑转向，每个车轮必须绕着不同的圆转动。由于内侧车轮转动圆半径较小，内侧车轮实际上要比外侧车轮转弯更急。 幻灯片10 If you draw a line perpendicular to each wheel, the lines will intersect at the center point of the turn. The geometry of the steering linkage makes the inside wheel turn more than the outside wheel. 如果你画出每个车轮的垂线，这些线会在转弯的中心点相交。转向机构的几何结构使得内侧车轮转向角度大于外侧车轮。 幻灯片11 There are a couple different types of steering gears. The most common are rack-and-Pinion and recirculating ball. 目前有很多不同形式转向器，最常见的就是齿轮齿条式转向器和循环球式转向器。 幻灯片12 12.1.1 Rack-and-pinion Steering12.1.1 齿轮齿条式转向器 Rack-and-pinion steering is quickly becoming the most common type of steering on cars, small trucks and SUVs. It is actually a pretty simple mechanism. 齿轮齿条式转向器迅速成为轿车、小型卡车和SUV最为常见的转向器。它有着非常简单的机械结构。 幻灯片13 A rack-and-pinion gear set is enclosed in a metal tube, with each end of the rack protruding from the tube. A rod, called a tie rod, connects to each end of the rack. The pinion gear is attached to the steering shaft. When you turn the steering wheel, the gear spins, moving the rack. The tie rod at each end of the rack connects to the steering arm on the spindle. 齿轮齿条转向器齿轮机构位于一个金属管内，齿条的两端从金属管中伸出。一根拉杆，被叫做转向横拉杆连接齿条的两端。齿轮连接在转向轴上。当你转动方向盘，带动齿轮转动，从而推动齿条。连接在齿条两端的转向横拉杆与转向轴上的转向节臂相连。 幻灯片14 The rack-and-pinion gearset does two things: 1. It converts the rotational motion of the steering