Automatic transmission

Part IV

The Saab 9000 is equipped with four-speed automatic transmission. Third gear features split torque transmission, and lock-up is employed in the fourth gear. In the split-torque third gear, 39% of the power is transmitted through the torque converter, and the remainder is transmitted mechanically. The lock-up function in the fourth gear bypasses the torque converter, and the drive is purely mechanical. This minimizes power loss and lowers sound level, in addition to improving performance and reducing fuel consumption.

As compared to automatic transmission of other manufacturers, the new four-speed Saab unit is extremely compact and light-weight. The drive shafts, etc. are the same as those fitted to the manual gearbox, which simplifies the service and fitting work, thus reducing the costs. As in the case of the manual gearbox, the automatic transmission can be removed from the car separately, by lowering the split sub-frame.

The selector lever is of ergonomic design, is correctly angled towards the driver and offers a firm grip. The gear indicator, located beside the gearshift, is clearly illuminated from the inside of the console. On cars with automatic transmission, the gear selected is also clearly indicated by the EDU instrument in front of the driver.

Answer the following questions to the text.

1) What is employed in the third and fourth gears of automatic transmission?

2) What minimizes power loss and lowers sound level?

3) Is the four-speed automatic transmission compact and light?

Active vocabulary

gearbox − коробка передач

gear − передача, шестерня

fuel consumption − потребление топлива

ratio − передаточное число

transversely mounted − поперечно смонтированный

final drive − главная передача

differential − дифференциал

front-wheel drive − передний привод

torque − крутящий момент

drive shaft − приводной вал

suspension − подвеска

bearing − подшипник

universal joints − универсальные шарниры

taper roller bearing − конусный роликоподшипник

load − нагрузка

gear gate − кулиса передачи

reverse gear − шестерня обратного хода

latch − замок, затвор

to drive (drove, driven) − приводить в движение

to lubricate (-ed; -ed) − смазывать

to load (-ed; -ed) − нагружать

to transmit (-ed; − ed) - передавать

to reduce (-ed; -ed) − снижать

to select (-ed; -ed) − избирать, выбирать

to choose (-ed; -ed) − отбирать

to comprise (-ed; -ed) − включать в себя, вбирать

to weight (-ed; -ed) − весить

to project (-ed; -ed) − выдаваться вперед

2. Pay attention to the sentences with non-finite forms of the verb (infinitive). Translate them.

1) The function of the gearbox is to transmit the engine power to the wheels as efficiently as possible.

2) Saab’s four-cylinder engine allows gear ratios to be chosen for more lively performance than is usually provided by cars with bigger engines.

3) It is designed to transmit very high power and torque, with ample margins of safety.

4) The fifth gear ratio has been specified to ensure optimum fuel economy.

5) All unnecessary covers and connection have been eliminated, to provide virtually perfect sealing.

6)The gear lever is spring-loaded to the 3rd/4th gates and is thus automatically centers in neutral, to ensure that the driver will never be in doubt as to the actual position of the gear lever.

3. Translate the following sentences with «due to» (благодаря чему-либо).

1) Gear - changing is easy due to the favourable locations of the synchromesh mechanisms.

2) Due to the strategies locations of taper roller bearings, the shafts have high stiffness under load.

4. Compare manual and automatic gearboxes in Saab 9000 according to the following plan.

1) The number of speeds in a gearbox;

2) Rotating masses;

3) Design;

4) Weight;

5) Fuel economy;

6) Reverse gear.

5. Discuss with your partner the two kinds of transmission using the following words.

Manual gearbox, simple design, gear-shifting effort, optimum fuel economy, synchromesh mechanisms, perfect sealing, well lubricated mechanisms, gear lever travel, reverse gear, automatic gearbox, split-torque third gear, to transmit, reducing fuel consumption, compact, light, sub-frame, EDU instrument.

UNIT 7

Text A. HEAVY VEHICLE SUSPENSION CONTROL.

1. Read and translate the text.

Heavy vehicles used for long-distance transportation experience widely varying road conditions and traffic situations. Optimum riding comfort and cargo protection must be maintained with full-, partial-, and no-loads without sacrificing driving safety and good handling characteristics.

With a soft suspension, ride comfort is achieved and impacts on the payload and cabin are reduced. However, optimized handling of a fully loaded vehicle requires increased damping that can result in drastically reduced comfort when the truck is empty or partially loaded. Therefore, a damping control system that can adapt to varying driving and load conditions is the ideal solution.

Manually adjustable and electronically controlled shock absorbers have been available in the upper class passenger car market for some years. The heavy truck market in Europe has offered such systems combined with controlled air suspensions for about two years. In Japan, coaches are equipped with a manually adjustable system.

For comfort, the optimum damping should be as low as possible, and for safety the damping should be higher at high damper velocity. The required damping force curve increases with a steep gradient at low damping speeds to reduce roll movement at higher damping speeds, the forces should " blow off" to reduce impacts on the bracketry.

Active vocabulary

absorb — поглощать, абсорбировать, впитывать

absorber — амортизатор

adjust — регулировать, настраивать, налаживать

adjuster — регулировочное устройство; сборщик

adjustment — регулировка, наладка

air suspension — подвеска на газовых (воздушных, пневматических) амор­тизаторах

available — доступный, имеющийся в наличии

cargo protection — защита (перевозимого) груза

coach — автобус

curve — кривая; искривлять

damp — смягчать (удар); демпфировать

damper — демпфер, глушитель, успокоитель, амортизатор

damping force curve — кривая силы демпфирования

drastic — решающий (фактор)

handle — ручка, поручень; перемещать, управлять, рассматривать (вопрос)

handling — управляемость

handling characteristics — характеристики управляемости

impact — удар

impacts on the payload — удары (механически воздействия) на полезную на­грузку

long-distance transportation — перевозки на дальние расстояния

maintain — обслуживать, поддерживать в рабочем состоянии

manually adjustable system — система с ручной регулировкой

optimum damping — оптимальное демпфирование (смягчение вибрации толчков, ударов)

payload — полезный груз

roll movement —поперечные колебания (кузова относительно продольной оси)

sacrifice — пожертвовать

shock — удар, толчок; ударять, трясти

shock absorber — амортизатор

solution — решение

steep gradient — крутой уклон, большой градиент

suspend — поддерживать, подвешивать; приостанавливать

traffic — перевозки

truck — грузовик

velocity — скорость

2. Answer the following questions:

1) What do heavy vehicles experience on the road?

2) May we sacrifice driving safety and good handling characteristics?

3) What is the ideal solution for a damping control system?

4) Are electronically controlled shock absorbers available in the car market?

5) Are there systems combined with controlled air suspension in the heavy truck market?

3. Match the following English words and Russian equivalents:

кривая перевозки полезный груз

поглощать груз поддерживать

доступный обслуживать демпфировать

грузовик без решающий

автобус пожертвовать пустой

регулировать управлять частично

скорость удар решение

4. Translate the following words and combinations:

long-distance transportation, cargo protection, without sacrificing, handling characteristics, impacts on the payload, shock absorber, air suspension, manually adjustable system, optimum damping, damping force curve, steep gradient, roll movement

5. Fill in the words from the text and translate the sentences.

Heavy vehicles used for long-______ experience widely varying road conditions and traffic situations.

Optimum riding comfort and cargo protection must be______

with full-, partial-, and no-loads without sacrificing driving safety and good _______ characteristics.

A damping control system that can ______ to varying driving and load conditions is the ideal _________

Manually adjustable and electronically ______ shock absorbers have been available in the upper class passenger car market for some years.

The heavy truck market in Europe has offered systems combined with controlled ___________ for about two years.

Text B. DRIVER, VEHICLE, AND ROAD.

1. Read the text and retell it.

Transportation is a system consisting essentially of three components: driver, vehicle, and road. If any one of these components fails, the whole system would fail, and conditions of hazards would be created on the road.

To provide a safe and efficient transportation system, it is necessary that all оf these three components should function in a well coordinated manner.

Driver. Studies have shown that 86% of the serious accidents are caused by drivers.

Vehicle. This component also plays a vital part in determining safety on roads. An unsafe vehicle is a source of constant danger in a road transportation system.

Road. To ensure maximum safety for the transportation system, it is necessary to plan and design highways on sound engineering techniques.

Modern roads. Modern roads should possess the following principal features. They should be designed according to the anticipated volume and speed of the traffic. Bends and gradients should always be slight. Visibility should not be hindered. They should be well lit. Hedge and tree planting on the road sides should provide a pleasant and interesting outlook to avoid monotony and boredom.

Road construction. In modern road construction, there is much greater recognition of the importance of the subsoil beneath a road. It is regarded as an integral part of the road. In case of mechanical stabilization granular or cohesive materials are added to the subsoil. In dry climates it is necessary to add substances helping to retain sufficient moisture.

Stabilization can be carried out by adding substances that harden the soil, an greatly increase its compressive strength. The constantly increasing volume of modern traffic involves the construction of numerous auxiliary structures, such as bridges, flyovers, tunnels, and underpasses. It is mainly these structures that will present problems for the engineers.

2. Answer the following questions:

1) What are the three main components of transportation?

2) What will happen if any one of these components fails?

3) What is necessary to provide a safe and efficient transportation system?

4) Which is the most important component?

5) What should be made to obtain maximum highways safety?

6) What should be made to avoid monotony and boredom on roads?

7) What role does the subsoil play in the modern road construction?

8) What does mechanical stabilization help to do?

3. Fill in the words from the text and translate the sentences.

Transportation is a system _________ essentially of three components: driver, __________, and road.

If any one of these_______ fails, the whole system would _________, and conditions of ___________ would be created on the road.

To_________ a safe and efficient transportation system, it is necessary that all of these three components ________function in a well ________manner.

Of all the above________ components driver is the most ________ component influencing safety on a road.

It is possible to obtain maximum ________ on highways by controlling their geometry, by ________of vertical and horizontal________ and providing adequate _______distances.

Hedge and tree planting on the _______ sides should provide a pleasant and interesting outlook to_______ monotony and boredom.

In modern road construction, there is much greater _________ of the importance of the subsoil __________ a road. It is ____________ as an integral part of the road.

In case of mechanical stabilization _______ or ________ materials are added to the subsoil. In dry climates it is necessary to add _________helping to _________sufficient __________

Stabilization can be carried out by adding substances that ________ the soil, and greatly increase its _________strength.

Text C. VEHICLES AIR CONDITIONING AND ENVIRONMENT.

1. Read the text and retell it.

In the near future, there will be 1 billion vehicles on the world's roads. As this number grows, so does environmental concernover fuel usage, emissions, and end-of-life disposal.

Today's vehicles are composed of many systems, each affectingcustomer satisfaction and environmental impact. One of many such systems is air-conditioning (A/C). Customershave come to expectthe high level of comfort and safetycurrent systems offer. As a result, A/C is now standard on most new vehicles while demandfor it is rising.

The refrigerant used in current systems is HFC-134a, which is classified as a global warming gasand is under scrutiny for possible phase-outin Europe. Emissions of HFC-134a from vehicle A/C systems account for about 0.1% of total world emissions. While the automotive industry is improving HFC-134a systems, it is evaluating two replacementrefrigerants: carbon dioxide (C0₂) and propane. The C0₂ system has higher operating pressures; if used, C0₂ would require all new A/C system components.

The use of propane requires only a modification of the existing HFC-134a system. In the secondary-loop propane system, a device in the engine compartmentchills a coolant(water-glycol). This coolant, not propane, circulates through the passenger compartment.

Although these technical options are promising, cost-benefit analysisis needed to understand the environmental and consumer benefits they offer compared toother potential vehicle fuel-saving technologies.

The international impact of SAE (Society of Automotive Engineers) documents on mobile A/C systems is far-reaching. SAE standards for system design, service equipment, and technician service proceduresand training have been used throughout the world. Equipment based on SAE's refrigerant recycling standardsis being used in both developed and developing countries to prevent unnecessary release of refrigerantto the atmosphere during service.

Vehicle makers will have to determinewhich systems need to bechangedto best manage total vehicle emissionsand then implementthose changes.

UNIT 8

Text A. AUTOMOTIVE MATERIALS.

1. Read and translate the text.

Materials are a fast-changing aspect for automotive engineers. Concept vehiclesdisplayed demonstrate that new uses of plastics, composites, aluminum, and other non-conventional materialsare to be a part of future automobiles and light trucks.

The automotive engineer for the next-generation vehicle must know the capability of a wide range of materials and the capability of the latest production processesfor these materials.