Unit 4 Camshaft

1. Memorize the new words and word-combinations:

1.to swing

2.chain wheel

3.the spring

4.distributor

5.oil pump

6.cam

7.rod

коливатися

ланцюгове колесо

ресора

розподілювач

масляний насос

кулачок

шток

2.Choose the right word:

1) He can (divide, drive, decide) a car well.

2) A car (follows, carries, moves) faster than a tractor.

3) The car ( really, suddenly, greatly) stopped at full speed at the side of the street.

4) The boys (forced, remarked, made) the car into the yard.

3. Read and translate the text.

Camshaft

As the crankshaft turns, it turns another shaft.This is the camshaft. There is a small wheel with teeth at one end of the crankshaft .This wheel is connected by a chain to a bigger wheel. This bigger wheel is at the end of a camshaft .So when the crankshaft turns, the camshaft turns too .The camshaft has cams on it. There are two cams for each cylinder. They open and close the inlet and exhaust valves on each cylinder. The cams turn with the shaft. As the high part of the cam comes up, it pushes up a rod. This rod pushes up one end of a lever (the rocker arm). The other end of a lever pushes down the valve and opens it.

On each valve there is a strong spring. As the lower part of the cam comes round, the spring forces the rocker arm up. This closes the valve. The turning of the shaft is set in a certain way. It makes the inlet and exhaust valves open and shut at the right time in the firing cycle.

There is a gear wheel in the middle of the camshaft. It does two things. It turns the distributor. It works the oil pump.

The camshaft turns the distributor. The distributor distributes etectricity to the sparking plug. The sparking plug fires the petrol and air mixture in the cylinder, at the right time in the firing cycle. So the camshaft controls the firing cycle.

4. Answer the questions:

1) What makes the camshaft turn?

2) What makes the valves move?

3) How many cams are there for each cylinder?

4) What is the purpose of the valve spring?

5. Fill in the gaps with the appropriate modal verb:

1) Motion . . .be defined as a continuous change in position.

2) This design ... be much relied upon because it is not accurate enough.

3) The filler cap ... be removed and the engine ... be refilled with oil.

4) If the float chamber is empty, the needle valve ... be blocked.

5) Air resistance is one of the main factors, which ... be taken into account in the design of a car.

6) The drain plug ... be cleaned and then replaced.

7) Oil machinery ... be replaced next month.

6. Translate into Ukrainian sentences with Passive Voice:

1) The petrol tank is usually fitted at the back of the car.

2) Air is mixed with petrol in the venture.

3) Petrol is drawn into the venture through the main jet.

4) The water pump is situated just behind the fan.

5) The clutch is operated by the clutch pedal inside the car.

6) The vehicle fails to accelerate properly when the pedal is depressed.

7) The operating cycle is shown in the table.

8) Each cylinder is provided with a piston.