Unit 6

(continued)

1. Memorize the new words and word-combinations:

1.shape

2.sequence of firing

3.smooth

4.tube

5.float

6.connecting rod

7.overcharging

8.flywheel

форма

порядок запалювання

плавний,легкий

труба

поплавець

шатун

заряджувати занадто

махове колесо

2. Translate the word-combinations:

special shape, the sequence of firing, the connecting rod, smoke and gases, smooth movement, voltage regulator, sparking plug

3. Translate the verbs, made by conversion:

flow - to flow, pump -to pump, force - to force, float - to float, valve -to valve, tube- to tube, form -to form, throttle -to throttle, swing - to swing, gear - to gear

4. Read and translate the text.

Electrical system

The firing sequence.

Explosion. Exhaust. Compression. Suction.

A car usually has four or three cylinders. It may have more. If all the cylinders fired together, the movement of the crankshaft would not be smooth. So they fire quickly one after the other. The camshaft controls this firing, and the crankshaft has a special shape for it. The sequence of firing in a four-cylinder engine is 1-3-4-2.

Cylinder 1 has fired. The piston is moving down. This movement is passed to the crankshaft through the connecting rod.

Cylinder 3 is compressing the air-petrol mixture.

Cylinder 4 is drawing in the air-petrol mixture from the carburettor.

Cylinder 2 is pushing out the smoke and gases after the explosion. In this way a smooth movement is given to the crankshaft.

The battery and the dynamo.

The battery only stores electricity. If we use too much, all the electricity will be gone. So something must put electricity back into the battery. The dynamo does this. The dynamo is a small machine that makes electricity. The crankshaft through a belt turns it. The electricity from the dynamo flows into the battery. This keeps the battery full of electricity (charged). A small instrument (the voltage regulator) stops too much electricity from flowing into the battery (overcharging). So the dynamo recharges the battery when the engine is running.

The starter motor.

The piston turns the crankshaft. If the crankshaft is turned, the pistons will move. The coil, rotor arms, contact breaker, camshaft, sparking plugs will begin to move. The engine will start. How do we turn the crankshaft? The starter motor does this. It is a powerful electric motor. When the starter switch is turned, electricity from the battery flows to the starter motor.

Two things happen:

a)A rod in the starter motor moves forward. There is a small gear wheel on the front of this rod. It meshes with the teeth of a large wheel (the flywheel). The flywheel is fixed on the back end of the crankshaft.

b)The starter motor turns. It turns the flywheel and crankshaft. The engine starts. The gear of the starter motor moves back from the flywheel.

5. Answer the questions:

1) What is the purpose of the starter motor?

2) Where does the starter motor get the electricity from?

3) What meshes with the teeth of the flywheel?

4) Where is the flywheel fixed?