防抱死制动系统外文翻译

1、what are antilock brakes system? antilock brakes are designed to help drivers avoid crashes. without anti-locks, hard braking can cause wheels to lock, sending a vehicle into a skid. wheel lockup can result in longer stopping distances, loss of steering control and, when road friction is uneven, los

2、s of stability if the vehicle begins to spin.the main advantage of anti-locks is that they can reduce these problems on wet and slippery roads. anti-locks work with a vehicle's normal service brakes to decrease stopping distance and increase the control and stability of the vehicle during hard b

3、raking.the principle behind anti-locks is that a skidding wheel provides less stopping force and control than a wheel that is rotating. anti-locks prevent wheels from skidding by monitoring the speed of each wheel and automatically pulsing the brake pressure on any wheels where skidding is detected.

4、 anti-locks don't make much difference in stopping distances on dry roads, although they can enhance vehicle stability and allow drivers to maintain steering control during emergency stops when conventional brakes might allow wheel lockup and skidding.how do antilock brakes system? since most ca

5、rs on the road today have some form of antilock brakes (abs) i think we should take a look at how they work and clear up some mis-information about them.as always, what i describe here is how most systems work in general. since different manufactures have their own versions of abs their values, spec

6、ifications and part names will differ. if you are having a problem with the abs on your vehicle you should always refer to the specific service and repair manuals for your vehicle.the abs is a four-wheel system that prevents wheel lock-up by automatically modulating the brake pressure during an emer

7、gency stop. by preventing the wheels from locking, it enables the driver to maintain steering control and to stop in the shortest possible distance under most conditions.during normal braking, the abs and non-abs brake pedal feel will be the same. during abs operation, a pulsation can be felt in the

8、 brake pedal, accompanied by a fall and then rise in brake pedal height and a clicking soundanti-locks differ among vehicles, but there are some basic similarities. each system has sensors that monitor the rotational speeds of selected wheels when brakes are applied. when one of these wheels approac

9、hes lockup, a control unit reduces brake pressure to that wheel (or set of wheels) just enough to allow rotation again. this typically happens many times per second, resulting in improved control and, on many wet and slippery surfaces, shorter stopping distances.differences among antilock brake syst

10、ems include the following:cars and many suvs have four-wheel systems with wheel-speed sensors on each wheel. in one type of system, the anti-locks reduce brake pressure to both rear wheels whenever one approaches lockup. brake pressure to the front wheels of four-wheel systems is controlled independ

11、ently to maximize stopping power, which is concentrated in the front. in four-wheel independent systems, each wheel is controlled individually, so when any one approaches lockup, the anti-locks reduce brake pressure to that wheel. some pickups and cargo vans have rear-wheel-only antilock systems to

12、address different braking needs when vehicles are loaded versus unloaded. the anti-locks monitor the rotational speeds of rear wheels only and release pressure to both when either is about to lock. tractor-trailers have separate antilock systems for the tractors and the trailers. ideally, both the t

13、ractor and trailer of a combination rig should have antilock brakes, but putting anti-locks on either component should produce improvement compared with conventional brakes. with anti-locks on the tractor only, a driver can maintain better steering control even if trailer wheels lock and the trailer

14、 swings. if only the trailer has anti-locks, trailer swing can be reduced even if steering control is lost. why don't anti-locks reduce stopping distances as much on dry roads as wet ones?adequate braking is easy to achieve on dry roads with or without antilock brakes. even if wheels lock, the c

15、oefficient of friction between tires and road surface still is relatively high, so a vehicle stops relatively quickly. it is even possible on some surfaces to stop sooner without anti-locks than with them, although such instances are rare. they occur, for example, when loosely packed snow or gravel

16、creates a "dam" effect in front of locked wheels, shortening the stopping distance more than anti-locks could.do car antilocks reduce crashes? although car anti-locks perform well on the test track, it is unclear whether they have made significant reductions in the number of on-the-road cr

17、ashes. a 1994 highway loss data institute (hldi) study1 and a subsequent 1995 study2 compared insurance claims for groups of otherwise identical cars with and without anti-locks, finding no differences in the overall frequency or cost of crashes for which insurance claims for vehicle damage are file

18、d. because anti-locks should make the most difference on wet and slippery roads, researchers also studied insurance claims experience in 29 states during winter months. even here they found no difference in the frequency of insurance claims for vehicles with and without antilock brakes. a 1997 insti

19、tute study3 and a 2001 update4 reported no difference in the overall fatal crash involvement of cars with and without anti-locks.according to one federal report, "the overall, net effect of antilock brakes" on both police-reported crashes and fatal crashes "was close to zero."5 a

20、 more recent federal report concluded that anti-locks reduce overall crash involvement risk by 6 percent for cars and 8 percent for pickups and suvs, but they have no effect on fatal crash risk.6 leonard evans, a researcher with general motors, reported that antilock-equipped cars were less likely t

21、o rear-end other vehicles but more likely to have other vehicles rear-end them.7 the net result was little effect on overall crash risk. in a study conducted for auto manufacturers, failure analysis associates reported a net beneficial effect of anti-locks on nonfatal crashes but no effect on fatal

22、crashes.8why aren't car anti-locks reducing crashes as expected?no one knows for sure why their test performance has not translated into a substantial reduction in real-world crashes. a possible reason is that the average motorist rarely experiences total loss of vehicle control, which anti-lock

23、s are designed to prevent. there also is evidence that many car owners do not know how to use antilock brakes effectively. a 1994 institute survey of drivers with antilock-equipped cars found that more than 50 percent in north carolina and 40 percent in wisconsin incorrectly thought they should pump

24、 the brakes.9are motorcycle antilock braking systems (abs) effective at reducing crashes?yes. results from recent studies by the institute and hldi compared crash rates for motorcycles equipped with optional abs against the same models without the option. the rate of fatal crashes per 10,000 registe

25、red vehicle years was 37 percent lower for motorcycles equipped with optional abs than for those same motorcycles without abs. in crashes of all severities, the frequency at which collision claims were filed was 22 percent lower for the abs models.10,11 based on these findings, the institute in apri

26、l 2010 petitioned the national highway traffic safety administration to require manufacturers to equip all new motorcycles with this technologyare anti-locks a new idea? are they widely available?the idea of anti-locks has been around for years. they first were used on airplanes in the 1950s. a rear

27、-wheel system was developed for the 1969 ford thunderbird, and the 1971 chrysler imperial had four-wheel anti-locks.modern anti-locks were first introduced on 1985 models. by the 1987 model year, they were standard or optional on about 30 domestic and foreign car models. availability soared to 90 mo

28、dels the next year. in the 2010 model year, anti-locks were on about 89 percent of all new cars sold and 99 percent of light trucks.12are anti-locks required on big truck rigs?in march 1995, the national highway traffic safety administration issued a rule requiring antilock brakes for heavy trucks,

29、tractors, trailers, and buses. all new truck tractors were required to have anti-locks after march 1, 1997, and they were mandatory on new air-braked trailers and single-unit trucks and buses after march 1, 1998. new single-unit trucks and buses with hydraulic brakes had to be equipped with anti-loc

30、ks after march 1, 1999. this was not the first antilock standard for us trucks. a federal brake standard took effect in 1975, but its antilock and stopping distance requirements were suspended after litigation in 1978. antilock brake systems have been required on all new trucks, buses, and trailers

31、in japan and the european union for several years.anti-locks are important for big trucks because of the poor braking capabilities of these vehicles compared with passenger cars. on dry roads, big trucks take much farther to stop 47 percent farther in institute tests. on wet and slippery roads, the

32、stopping distance disparity is even worse. tractor-trailer combinations also have the potential for loss of control and jackknifing on both dry and, especially, slippery roads. (jackknifing occurs when the rear wheels of a tractor lock up, allowing the tractor to skid and spin so that it folds into

33、the trailer. this also can happen when trailer wheels lock and cause the trailer to swing around the tractor.) antilock brakes not only reduce stopping distances on wet and slippery roads, but also help drivers maintain control.the standard for tractors requires antilock control on the front axle an

34、d at least one rear axle. on at least one of the tractor axles, each wheel must be independently controlled by an antilock modulator. this ensures that a wheel provides shorter stopping distances and optimal braking force on all surfaces, especially on roads where one side is slipperier than the oth

35、er. for semi-trailers, at least one axle must have anti-locks. full trailers must have anti-locks for at least one front and one rear axle.a 2010 report by the national highway traffic safety administration concluded that anti-locks on tractors reduced crash involvement by 3 percent.13 however, ther

36、e was no significant effect on fatal crashes.are anti-jackknifing devices a substitute for truck antilock?no. some devices marketed for trucks purportedly would prevent jackknifing in emergency braking situations. one device on the market mechanically limits the amount a trailer can swing around the

37、 pin that connects it to the tractor. this kind of device is less effective than antilock brakes. although it may prevent jackknifing, it does not prevent a truck's wheels from locking up, nor does it provide equivalent handling stability on wet or dry roads防抱死制动系统是什么？防抱死制动系统的设计是帮助司机避免发生事故。在没有防抱

38、死系统的情况下，硬制动可能导致车轮锁死，导致车辆打滑。如果车辆打滑车轮锁死，会导致更长的制动距离，转向失控，路面摩擦不平衡时，会减少车辆的稳定性。的防抱死的主要优点是，在湿滑道路上他们可以减少这些问题。 防抱死工作是减少车辆的正常的刹车制动距离，在急刹车时，增加车辆的控制性和稳定性。防抱死的原则是当车辆在告诉旋转而储量打滑时，减少制动力来提高控制。 防抱死监测每个车轮的速度，并自动脉冲任何检测打滑的车轮上的制动压力，防止车轮打滑。防抱死系统在干燥道路上的制动距离和没有该系统的刹车距离相差不大，但是他们可以在紧急停车时提高车辆的稳定性，并让司机在紧急情况下能够保持转向控制，然而普通的刹车系统可能

39、会导致车轮锁死和打滑。防抱死制动系统怎么工作？现在在道路上行驶的大部分轿车都装备了abs系统，我认为我们有必要了解abs怎么工作以及一些abs的误导一直以来，我们只是描述大概描述大部分系统怎么工作，由于不同的生产商在abs上有不同的商业价值定位和有些部分的叫法不同。如果你车子的abs有问题的话你应该参考自己车上的特殊服务和维修手册。abs系统是四驱系统在紧急刹车时防止车轮锁死的制动系统。免于车轮即将抱死的危险，它能保持车轮的总体控制以及在大部分情况下以最短距离刹车。虽然防抱死系统因车而异，但也有一些基本的相同之处。每个系统都有监控选定的车轮施加制动时的转速传感器。当其中一个车轮接近锁定，控制单

40、元减少了制动轮（或车轮），刚够再次允许旋转的压力。这通常发生每秒多次，可以改进控制，在许多湿滑的表面使得制动距离更短。防抱死为什么在干燥道路和潮湿道路上减少的制动距离不同呢？汽车和许多越野车有四个轮速传感器即每个车轮上都有轮速传感器。在一个系统类型中，无论什么时候有那个轮子接近锁定，刹车系统都会使每个轮子减少制动力。独立控制四轮系统前轮制动压力，制动力集中在前面时可以以最大限度地减少制动力。四轮独立的系统，每个车轮单独控制，所以，当任何一个轮子接近锁定，防抱死减少该轮的制动压力。一些皮卡和小型货车的只有后轮拥有防抱死系统，通过车辆装载与卸载，以满足不同的制动需求。无论是否锁定，防抱死通过监测后

41、轮的转速来释放压力。拖拉机拖车的拖拉机和拖车有独立防抱死系统。理想的情况下，拖拉机和拖车的组合钻机应该有防抱死制动系统，但把两种成分防抱死相比与传统的制动器。拖拉机防抱死只能保证司机可以保持较好的转向控制，即使拖车车轮锁和拖车摆动。如果只有拖车防抱死，拖车摆动可以减少即使方向盘失去控制。汽车防抱死能减少事故吗？虽然汽车防抱死执行测试赛道上的结果让人满意，目前还不清楚他们是否能够使道路交通事故数量显着减少。提出1994年的公路损失资料研究所（hldi）研究和随后的1995年研究二的，相同的车组相比，保险理赔只有防抱死系统的有无，发现在整体频率无显着差异。 因为防抱死只在湿滑道路上有显著差异，研究

42、人员还研究在29个州在冬季几个月的保险理赔经验。即使在这里，他们没有发现任何与防抱死制动系统的车辆在保险索赔的频率差异。 1997年的研究所study3和2001年update4报告没有在整体汽车的致命交通意外介入没有防抱死的差异。根据一项联邦报告“，防抱死制动系统的整体净效应”两个警察报告事故和致命事故“接近于零”。最近的一个联邦报告的结论，防抱死减少了参与风险车6整体崩溃和8皮卡和suv，但它们不会影响致命交通意外。伦纳德埃文斯，通用汽车公司的研究员，报告说，配备防抱死，汽车不太可能追尾其他车辆，更可能其他车辆追尾他们。净结果是影响不大，整体崩溃的风险。在汽车制造商进行的一项研究，失效分析协会报告非致命性死机的防抱死净有利影响，但没有致命效果为什么有防抱死系统的汽车不能减少事故的期望？没有人知道为什么他们的测试表现没有反映到现实的事故中。一个可能的原因是，一般驾驶者很少有车辆失控的经历而车辆失控是防抱死系统设计避免的，许多车主不知道如何有效使用防抱死制动系统。 1994年的研究所的调查，50以上，在北卡罗莱纳州和威