車專業(yè)英語(yǔ)Unit-5-Passage-B課件

1、Unit Five Automobile Braking System Passage BBasic Brake Parts and Safety Brake SystemTypical braking system has the following basic parts: brake pedal, brake booster, master cylinder, brake lines and brake fluidas shown in Fig.5-8Brake pedalBrake pedal located on the right foot side in the car can

2、amplify the force of your leg and evenly transmit it to the brake fluid when the right foot steps on the pedal (see Fig.5-9). Brake boosterBrake booster mounted on the firewall between the brake pedal and master cylinder increases the force applied to the pistons in the master cylinder so that the c

3、ar can stop with less effort The two most common types of power brake boosters are vacuum booster and hydraulic booster, both of which accomplish the same thingMaster cylinderA master cylinder has actually two completely independent working chambers respectively with one piston, each controlling two

4、 wheels If only the two of the wheels lose their brakes, the other two wheels will still be able to stop the car On the top of the master cylinder is a brake fluid reservoir that is transparent so as to see the fluid level without opening the cover (see Fig.5-10).Brake linesThe brake lines run from

5、the master cylinder along the frame of the car to each wheel (see Fig.5-8). The lines are made of steel and reinforced rubber hoses which are flexible enough to use only at the front wheels and rear axles where the suspension system works and wheels turn when you steerBrake fluidBrake fluid travels

6、from the master cylinder to the wheels through the brake lines It is special oil that has specific properties It must withstand cold temperature in winter without thickening as well as very high temperature in summer without boilingSafety brake systemOne cannot think of the safety brake system witho

7、ut thinking of ABS, nor of ABS without EBD, EBA and ESC, etcABS, short for Anti-lock Brake System, is designed to prevent the car from skidding on a wet and slippery road, and make the car shorten brake distance and stop in a straight line without loss of the directional controlwithout loss of the d

8、irectional controlABS consists of ECU (Electronic Control Unit), 4 wheel speed sensors and APV (Anti-lock Pressure Valve) as shown in Fig.5-11 ECU continuously monitors the rotating speed of each wheel through the 4 wheel speed sensors When one or more wheels are going to lock up, the ECU immediatel

9、y commands the APV to ease the brake pressure on the affected wheels ABS “pumps” brakes up to 15 times per second, much faster and more effective than a human driver canEBD, short for Electronic Brake-force Distribution, as the subsystem of ABS, is designed to automatically modulate the brake force

10、on the front wheels and the rear wheels according to the load of the car, the condition of the road and the adhesion between the tire sand road surface in order to get more balanced and closer to the ideal brake force distributionEBA, short for Emergency Brake Assist, is designed to keep the electro

11、nic eye on how you are braking, and if you suddenly get into an emergency and have to stop your car shortly, EBA automatically boosts the brake force to help you in order to save you in an emergencyESC, short for Electronic Stability Control, is designed to keep the car from rolling over in a panic

12、swerve when running on a wet and slippery road It uses some sensors such as wheel speed sensors, steering wheel position sensors and yaw sensors to determine whether the car goes the right direction you want If the car is not going in the direction you want, ESC can apply the brakes on individual wh

13、eels to bring the car back under controlNew Words and Expressionsamplify mplifai vt 放大, 擴(kuò)大transparent trnsprnt adj 透明的frame freim n 車架fluid level液面, 液位reinforced riinfst adj 加強(qiáng)的thickening ikni n 增稠boiling bili n 起沫skidding skidi n 側(cè)滑滑行, 漂移slippery slipri adj 滑的command kmnd vt 命令, 指揮ease iz vt 減輕, 緩和

14、affected fektid adj 受到影響的New Words and Expressionspump pmp vt 點(diǎn)制動(dòng)modulate mdjuleit vt 調(diào)節(jié), 調(diào)整adhesion dhin n 附著力tire tai n 輪胎、 車胎swerve swv vi 突然轉(zhuǎn)向, 突然轉(zhuǎn)彎individual individul adj 個(gè)別的directional control 方向控制in a panic 驚慌地steering wheel 轉(zhuǎn)向盤(pán)Common Automobile Termsfirewall faiw: l n 發(fā)動(dòng)機(jī)艙壁brake booster制動(dòng)助力器master cylinder制動(dòng)主缸, 制動(dòng)缸braking line/ brake line制動(dòng)管路anti-lock brake system (ABS) 防抱死制動(dòng)系統(tǒng)electronic control unit (ECU) 電控單元anti-lock pressure valve (APV) 防