交通运输专业英语

Lesson 6 The Steering System

1 The Steering Gear

The steering gear mechanism enables the driver to turn the front wheels of the car. The mechanism consists of a steering gear box, pitman arm, drag link, tie rods, steering arms, and steering knuckles, the latter supporting the front wheels. (Fig.6.1)

转向齿轮机构使司机能够转动轿车的前轮。该机构由转向器、转向垂臂、纵拉杆、转向横拉杆、梯形臂和转向节构成，转向节支承着前轮。（图6.1）

Turning the steering wheel turns the steering shaft to which a worm gear is attached within the steering gear box.

转动转向盘使转向轴转动，并带动转向器内与之相连的蜗杆转动。The steering worm moves a roller through a part of an arc, the motion of which is transmitted to the pitman arm, which moves back and forth across the width of the frame.

转向蜗杆推动滚筒移动一段弧线，滚筒的运动被传递到转向垂臂，转向垂臂在整个车架宽度上来回移动。

Several arrangements of rods and levers are in common use but, in general, a drag link, connected to the pitmen arm, transmits the movement to tie rods which are connected to the steering arms.

通常使用几种杠杆的布置方式，但是总的来说，与转向垂臂相连的纵拉杆把运动传递到与转向臂相连的横拉杆。

Sideward movement of the steering arms turns the steering knuckles, and the wheels, as they are pivoted on front end support mechanism.

由于转向节和车轮安装在前端支承装置的枢轴上，转向臂的横向运动可使其转动。

There are two types of steering systems: manual steering systems and power steering systems. In the manual type, the driver does all the work of turning the steering wheel, steering gear, wheels, and tires. In the power type, hydraulic fluid assists the operation so that the driver’s effort is reduced.

有两种类型的转向系：手动转向系和动力转向系。在手动类型中，司机做所有的转动转向盘、转向齿轮、车轮和轮胎的工作。在动力类型中，液压的流体帮助完成这个操作，以便司机省力。

A typical power steering system needs a power steering pump and reservoir in addition to the steering gear [Fig.6.2].

一个典型的动力转向系除了需要转向齿轮外，还需要一个动力转向泵和油箱[图6.2]。

These parts store the hydraulic fluid and provide the hydraulic pressure to assist the steering. In most instances, a V-belt from the engine powers the hydraulic pump.

这些部件储存液压流体，并提供液体压力以帮助转向。在大部分情况下，从发动机的三角带驱动液压泵。

Hoses lead from the pump to the steering gear and back to the pump.

软管从泵引入到转向齿轮，再回到泵。

In steering gear box the gear is slightly larger and has other parts. The wormshaft is the same in both systems.

在转向器中，齿轮稍微大一点，并且有其它的部件。蜗杆轴在两种系统中相同。

Instead of a ball nut, though, the power steering system uses a power piston or rack piston in steering gear box.

但是，在转向器中，动力转向系统不使用球螺母，而使用一个动力活塞或者齿条活塞.

The power piston has teeth on one side that mesh with the sector teeth. The forward and backward motion of the power piston moves the sector, pitman shaft, and steering linkage.

动力活塞在与扇形齿轮齿啮合的一侧有齿。动力活塞的向前和向后运动移动扇形齿轮、转向臂轴和转向连接。

The power steering gear also uses a control valve to send hydraulic fluid into the steering gear at the right time.

动力转向齿轮同时地使用一个控制阀来在确切的时间把液压的流体输送到转向齿轮。

When the steering wheel starts to move in either direction, the valve opens its ports to send fluid under pressure into the main chamber of the steering gear.当转向盘开始在任一方向移动时，阀打开出口把有压力的流体传送到转向齿轮的主腔里。

The fluid pushes against the power piston and assists the motion of the steering wheel.

流体推动动力活塞，并帮助转向盘的运动。