I. Read the text paying attention to the vocabulary.
The rotational force of the engine’s crankshaft turns other shafts and gears that eventually cause the drive wheels to rotate. The various components that link the crankshaft to the drive wheels make up the drivetrain. The major parts of the drivetrain include the transmission, one or more driveshafts, differential gears, and axles.
The transmission, also known as the gearbox, transfers power from the engine to the driveshaft. As the engine’s crankshaft rotates, combinations of transmission gears pass the energy along to a driveshaft. The driveshaft causes axles to rotate and turn the wheels. By using gears of different sizes, a transmission alters the rotational speed and torque of the engine passed along to the driveshaft. Higher gears permit the car to travel faster, while low gears provide more power for starting a car from a standstill and for climbing hills.
The transmission usually is located just behind the engine, although some automobiles were designed with a transmission mounted on the rear axle. There are three basic transmission types: manual, automatic, and continuously variable.
A manual transmission has a gearbox from which the driver selects specific gears depending on road speed and engine load. Gears are selected with a shift lever located on the floor next to the driver or on the steering column. The driver presses on the clutch to disengage the transmission from the engine to permit a change of gears. The clutch disk attaches to the transmission’s input shaft. It presses against a circular plate attached to the engine’s flywheel. When the driver presses down on the clutch pedal to shift gears, a mechanical lever called a clutch fork and a device called a throwout bearing separate the two disks. Releasing the clutch pedal presses the two disks together, transferring torque from the engine to the transmission.
An automatic transmission selects gears itself according to road conditions and the amount of load on the engine. Instead of a manual clutch, automatic transmissions use a hydraulic torque converter to transfer engine power to the transmission.
Instead of making distinct changes from one gear to the next, a continuously variable transmission uses belts and pulleys to smoothly slide the gear ratio up or down. Continuously variable transmissions appeared on machinery during the 19th century and on a few small-engine automobiles as early as 1900. The transmission keeps the engine running at its most efficient speed by more precisely matching the gear ratio to the situation. Commercial applications have been limited to small engines.
II. Learn the vocabulary to the text.
Gearа) шестерня
gears grind — шестеренки стачиваются; gears jam — шестеренки заедают; gears lock — шестеренки заклинивает; gears mesh — шестеренки крутятся;
б) передаточный механизм, привод
a worm gear — червячный привод; in gear — включенный, сцепленный, действующий;
out of gear — не включённый, недействующий, неработающий; to throw out of gear — выключить передачу; to get into gear — включить передачу; включиться в работу
в) зубчатая передача
to change gears , to shift gears — переключать передачу; to go into 1st, 2nd, etc. gear — переключаться на 1-ю, 2-ю и т. д. cкорость; bottom gear , low gear — нижняя, первая передача; high gear , top gear — верхняя передача; reverse gear — задняя передача.
gearbox1) коробка передач, коробка скоростей; тж. коробка подач
2) редуктор
crankshaft -коленчатый вал
drivetrain– ходовая часть
driveshaft – карданный вал
differential gears - дифференциальная передача
torque - вращающий момент
rear axle – задняя ось
continuously variable - 1) непрерывная переменная 2) с бесступенчатым регулированием
steering column - рулевая колонка
shift lever - рычаг переключения передач или скоростей
clutch –сцепление
input shaft – ведущий вал
circular plate -ведомый диск
clutch disk – нажимной диск
clutch fork – вилка выключения сцепления
throwout bearing – рычаг выключения передачи
III. Make your own sentences using the word combinations with the word gear.
IV. Make up questions to the information that you’ve read. Let your partner answer your questions.