Lesson 3

Injection nozzle

Injection nozzle or valves are provided for each cylinder and are of two general types: open or closed types. The open type nozzle usually is provided with check valves inside the nozzle body to stop the flow of fuel. These check valves are held closed by strong springs, which snap shut as soon as the injection pressure is released. The closed type contains a spring-loaded valve near or at the orifice. The fuel pump controls the injection of the open type, and a mechanical cam action, or hydraulic action by the fuel pressure, controls the closed type.

Atomization of the fuel is fully as important in diesel as in carburettor engines and is accomplished in a manner somewhat similar. The main difference is that, in the diesel, atomization, vaporization and combustion all take place within the combustion chamber, whereas in gasoline engines, atomization takes place in the carburettor and vaporization occurs in the carburettor, manifold, and cylinder.

In the diesel the fuel is injected at high velocity through fine orifices and jets into the cylinder or precombustion chamber, where it is atomized, vaporized and ignited.

The injection nozzle introduce fuel into the combustion chamber either by high pressure from the injection pump, which forces the injection valve open or by mechanically opening the valve against pressure. Nozzles and valves are of hardened steel which must withstand combustion temperatures and high pressures without distortion and corrosion. Coil springs hold the valves closed until the time of opening, and the steel must be perfect, since any leakage will cause to form around the orifices, resulting in poor performance, engine knocking, and smoky exhaust.

Since ignition timing, rate of burning, and amount of fuel all depend upon the operation of the injector, timing of its action must be accurate and positive. The timing of the injection is coordinated with valve timing.

Задание 1. Прочтите слова, обращая внимание на чтение

буквы o.

Injection, nozzle, provided, flow of fuel, strong, orifice, contains, carburettor, accomplished, somewhat, atomization, vaporization, combustion, gasoline, occurs, manifold, velocity, atomized, vaporized, introduce, forces, distortion, corrosion, coil, poor, performance, poor, amount, coordinated.

Задание 2. Переведите следующие слова и словосочетания на русский язык.

1. Injection nozzle, injection pressure, injection pump, injection valve.

2. Injection pressure, fuel pressure, high pressure.

3. Check valve, spring-loaded valve, valve timing.

4. Atomization, vaporization, combustion, without distortion and corrosion.

5. Strong springs, coil springs, spring-loaded valve.

6. Nozzle body, fuel pump, mechanical cam action, main difference, gasoline engines, manifold, at high velocity, the hardened steel, leakage, poor performance, engine knocking, smoky exhaust, rate of burning, ignition timing.

7. To snap shut, to take place, to occur, to be provided with, to be held closed, to release, to contain, to atomize, to vaporize, to ignited, to introduce, to force, to withstand, to cause, to depend upon, to jet.

Задание 3. Определите видовременную форму сказуемого и переведите на русский язык.

Are provided for, is provided with, are of two general types, are held closed by, snap shut, is released, contains, controls, is accomplished, take place, takes place, occurs, is injected, jets, is atomized, introduce, forces, must withstand, must be perfect, will cause, depend upon, must be accurate, is coordinated with.

Задание 4. Найдите в тексте ответы на следующие вопросы.

1. What type of injection nozzle or valve exists?

2. What is used to stop the flow of fuel inside the open-type nozzle?

3. What are strong springs used for?

4. What is there in the closed type nozzle for the same purpose?

5. What feature is common and important for diesel and carburettor engines?

6. What is the main difference between diesel and gasoline engines?

7. What way is fuel introduced into the combustion chamber?

8. Why are nozzles and valves made of hardened steel?

Задание 5. Составьте одно сложное предложение из нескольких простых.

1. Injection nozzle or valves are provided for each cylinder. They are of two general types: open or closed types.

2. The open type nozzle usually is provided with check valves. It stops the flow of fuel.

3. These check valves are held closed by strong springs. They snap shut as soon as the injection pressure is released.

4. The main difference is the following. In the diesel, atomization, vaporization and combustion all take place within the combustion chamber. In gasoline engines, atomization takes place in the carburettor. Vaporization occurs in the carburettor, manifold, and cylinder.

5. In the diesel the fuel is injected at high velocity through fine orifices. It jets into the cylinder or precombustion chamber. There it is atomized, vaporized and ignited.

6. The injection nozzle introduces fuel into the combustion chamber by high pressure from the injection pump. It forces the injection valve open.

7. Nozzles and valves are of hardened steel. They must withstand combustion temperatures and high pressures without distortion and corrosion.

8. Coil springs hold the valves closed until the time of opening. The steel must be perfect. Any leakage will cause to form around the orifices. It will result in poor performance, engine knocking, and smoky exhaust.

Задание 6. Составьте аннотацию данного текста.

Задание 7. Разыграйте следующие ситуации.

а) расскажите о работе впрыскивающей форсунки от имени студента, принимающего участие в научно-технической конференции;

б) расскажите о работе впрыскивающей форсунки от имени руководителя завода по производству форсунок;

с) расскажите о работе впрыскивающей форсунки от имени инженера, приглашенного на завод с целью ознакомления с их производством.

Задание 8. Переведите следующий текст на английский язык.

Самый дешевый и экономичный двигатель внутреннего сгорания был создан на Балтийском заводе (the Baltic plant) в Санкт-Петербурге в 1899 году. Оказывается (to appear), в высоком давлении (pressure) при сжатии заключается основное преимущество (advantage) дизеля.

Такое давление дает наилучшее использование горючего.

Топливная форсунка (fuel nozzle) - прибор, разбрызгивающий(to spray) горячее.

К моменту рабочего хода (near the power stroke) поршня насос подает(the pump forces) небольшую порцию горючего в форсунку, где оно подхватывается струей (stream) сжатого воздуха и распыляется (to atomize) в камере сгорания.