What is the top dead centre ответы на вопросы

THE ENGINE

1. The engine is the source of power that makes the car move. It is usually called an internal combustion engine because gasoline is burned within its cylinders or combustion chambers. Most automobile engines have six or eight cylinders.

The operating cycle of the four-stroke engine that takes place in the engine cylinder can be divided into four strokes. The upper limit of the piston movement is called the top dead centre. The lower limit of piston movement is called the bottom dead centre. A stroke is the piston movement from the top dead centre to the bottom dead centre or from bottom dead centre to the top dead centre. In other words, the piston the completes a stroke each time it changes the direction of its motion.

3. Where the entire cycle of events in the cylinder requires four strokes (two crankshaft revolutions), the engine is called a four-stroke cycle engine. The four strokes are: intake, compression, power and exhaust.

4. Two-cycle engines have also been made, and in such engines the entire cycle of events is completed in two strokes or one revolution of the crankshaft.

5. On the intake stroke the intake valve is opened. The mixture of air and vaporized gasoline is delivered into the cylinder through the inlet valve. On the compression stroke the inlet valve is closed so that the mixture can be compressed. On the power stroke both valves (inlet and exhaust) are closed in order to raise pressure during the mixture combustion. On the exhaust stroke the exhaust valve is opened to exhaust the

4. Переведите на русский язык в письменной форме абзацы 2 и 5.

5. Найдите соответствующие ответы на вопросы и напишите их в той последовательности, в которой заданы вопросы:

1. What is the top dead centre?

2. What is the bottom dead centre?

3. When the engine is called a four-stroke cycle engine?

4. When the engine is called a two-cycle engine?

5. What kind of strokes can the events in the engine cylinder be divided into?

a. When the entire cycle of events is completed in two strokes.

b. The lower limit of the piston movement.

с. The upper limit of the piston movement.

d. When the entire cycle of events in the cylinder is completed in four strokes.

e. Intake, compression, power and exhaust strokes.

6. Закончите предложения, выбрав соответствующий вариант окончания:

1. An internal combustion engine is called so because gasoline is burned.

a) inside the combustion chamber

b) outside the combustion chamber

2. The upper limit of the piston movement is called.

3. The lower limit of the piston movement is called.

a) the bottom dead centre

b) the top dead centre

4. The four-cycle engine requires.

a) two strokes of piston movement

b) four strokes of piston movement

5. The mixture of air and gasoline is delivered into the cylinder.

Переведите на русский язык в письменной форме абзацы 1,3,5 и 6.

5. Найдите соответствующие ответы на вопросы и напишите их в той последовательности, в которой заданы вопросы:

Вопросы

1. What are the main basic parts of the automobile?

2. What does the chassis consist of?

3. What units does the power train contain?

4. What is the function of the clutch?

5. Why are brakes needed?

Ответы

a. The clutch, gearbox, cardan shaft and the final drive.

b. Freeing the engine from the gearbox.

c. The power plant, the chassis and the body.

d. A power train, frame with axles, wheels and springs.

e. To slow or stop the car.

6. Закончите предложения, выбрав соответствующий вариант окончания:

3. The mechanism used for connecting a) brakes;

c) steering system.

4. The unit carrying the power from the a) power plant;

5. The instrument meas­uring the speed of the car a) heater;

Вариант 9

1. Найдите в правой колонке русские эквиваленты слов и словосочетаний:

1. internal combustion engine a. поршень

2. combustion chamber b. верхняя мертвая точка

3. stroke c. четырехтактный двигатель

4. piston d. коленчатый вал

5. top dead centre e. отверстие клапана

6. bottom dead centre f. двигатель внутреннего сгорания

7. four-stroke cycle engine g. нижняя мертвая точка

8. two-cycle engine h. топливная система

9. crankshaft i. такт впрыска (топлива)

10. intake stroke j. двухтактный двигатель

11. valve opening k. камера сгорания

12. fuel system l. ход, такт (поршня)

13. power stroke m. выхлоп

14. exhaust n. рабочий ход поршня

2. Переведите на русский язык встречающиеся в тексте интерна­циональные слова:

cylinder, automobile, limit, centre, cycle, compression, gas.

3. Простите текст и выполните следующие за ним упражнения:

2. The operating cycle of the four-stroke engine that takes place in the engine cylinder can be divided into four strokes. The upper limit of the Piston movement is called the top dead centre. The lower limit of piston Movement is called the bottom dead centre. A stroke is the piston movement from the top dead centre to the bottom dead centre, or from the bottom dead centre to the top dead centre. In other words, the piston completes a stroke each time it changes the direction of its motion.

3, Where the entire cycle of events in the cylinder requires four stroked (two crankshaft revolutions), the engine is called a four-stroke cycle engine. The four strokes are: intake, compression, power and exhaust.

4 Two-cycle engines have also been made, and in such engines tin! entire cycle of events is completed in two strokes or one revolution of the crankshaft.

5. On the intake stroke the intake valve is opened. The mixture of; and vaporized gasoline is delivered into the cylinder through the inlet valve,

On the compression stroke the inlet valve is closed so that the mixture can be compressed.

On the power stroke both valves (inlet and exhaust) are closed in order to rise pressure during the mixture combustion.

On the exhaust stroke the exhaust valve is opened to exhaust the residual gas.

Переведите на русский язык в письменной форме абзацы 2 и 5.

5. Найдите соответствующие ответы на вопросы и напишите их в той последовательности, в которой заданы вопросы:

Вопросы

1. What is the top dead centre?

2. What is the bottom dead centre?

3. When is the engine called a four-stroke cycle engine?

4. When is the engine called a two-cycle engine?

5. What kind of strokes can the events in the engine cylinder be divided into?

Ответы

a. When the entire cycle of events is completed in two strokes,

b. The lower limit of the piston movement,

c. The upper limit of the piston movement.

d. When the entire cycle of events in the cylinder is completed in four strokes.

e. Intake, compression, power and exhaust strokes.

6. Закончите предложения, выбрав соответствующий вариант окончания:

1. An internal combustion engine a) inside the combustion chamber;

is called so because gasoline is burned. b) outside the combustion chamber.

4. The four-cycle engine requires. a) two strokes of piston movement

b) four strokes of piston movement.

5. The mixture of air and gasoline is a) on the power stroke; on the exhaust stroke;

delivered into the cylinder. b) on the intake stroke; on the compression stroke.

Вариант 10

1. Найдите в правой колонке русские эквиваленты английских слов и словосочетаний:

1. to deal (with) а. программное обеспечение

2. to elaborate (to work out) programs b.отвечать современным требова­ниям

3. computer-aided-design с. аппаратная часть

4. computer-aided-manufacturing d.иметь дело (с кем-л., чем-л.)

5. to meet up-to-date demands (requirements) е. автоматизированное проектиро­вание

6. software f. защищать от вирусов

7. hardware g. предлагать решения

8. to offer solutions h.разрабатывать программы

9. to solve problems i. автоматизированное производ­ство

10. to defend from viruses’ j. решать проблемы

2. Переведите на русский язык встречающиеся в тексте интерна­циональные слова:

specialist, productivity, optimal, problem, logic, operation, program, virus, expert, instruction, method, computer, mathematics, designer, manager, calculator.

2. Прочтите текст и выполните следующие за ним упражнения:

1. Computer science is a part of an applied mathematics. Specialists in computer science say that this field of knowledge is very interesting because it deals with computer-aided-design (CAD) and com­puter-aided-manufacturing (CAM).

2. Computers are intended to improve the productivity of labour of scientists, designers, engineers, managers, and other specialists, because computers offer quick and optimal solutions. One of the main goals of using CAD/CAM is to shorten the time between designing and manufacturing.

3. Moreover, computers came in our life and to our houses and now we Ican solve our everyday problems with their help.

4. Computers can be divided into simple and complex devices. Simple j computers such as calculators can perform addition, subtraction, \ multiplication and division. As far as complex computers are concerned they can do different logical operations and some of them even have artificial intelligence.

5. Thus in order to elaborate up-to-date and inexpensive programs as j well as to defend them from viruses, it is important to know some programming languages.

6. There are low-level programming languages such as a machine l language and an assembly language and high-level programming languages, for instance, FORTRAN, PASCAL, ADA, C, BASIC, etc. 1

Top Dead Center – Is When The Piston, Is At The Top Of Its Stroke

Top Dead Center (TDC) refers to, the point when the piston is at the absolute top of its stroke.

So, a piston can be at Top Dead Center (TDC), on the compression stroke or on the exhaust stroke.

As a general reference point, or when installing a distributor, (TDC) on the compression stroke is required.

So, top dead center, can usually be found, by looking at timing marks. But, on some engines, these marks may be lost or hidden. Fortunately, there’s an easy way to discover top dead center, without the use of any timing marks.

So, being able to accurately find Top Dead Center (TDC) is a critical step, when working on any engine. Consequently, there are actually many ways to do it. But, in this article we wanted to show you a simple, quick and practically foolproof method for finding it.

Like, when your, building an engine or want to make sure, the timing marks on your damper are correct.

So, if you’re relatively new to engine work and have never, pulled the distributor or damper from your engine. Then, finding Top Dead Center (TDC) on piston #1, becomes an instant priority. Finding Top Dead Center (TDC), is an essential skill, for assembling and tuning engines. And, is even a necessity for performing some engine diagnostic tests, such as a cylinder leak down test.

What Is Top Dead Center (TDC)

Consequently, (TDC) is the position of an engine’s piston, when it is at the very top of its stroke.

Depending on whether you need to be on the compression stroke or not, there are many methods:

STEP ONE: Finding top dead center.

So, the first thing you would want to do is, remove all the spark plugs. Consequently, the reason for this is, you are going to be turning the engine over by hand. Well, most likely with a wrench, on the harmonic balancer nut. This will make it a lot easier to turn.

STEP TWO:

I like to use the hose from my compression tester gauge. ( Make sure to remove the schrader valve from the hose, before you start ). Start, by screwing the hose into the #1 cylinder.

Compression Tester Hose

STEP THREE:

At this point, there are a few ways to confirm the compression stroke:

Finger on Hose

Most old school mechanics would just, use the finger method. Place one finger over over the end of the hose, then rotate the crankshaft. During transition between exhaust and intake strokes, when one or both valves are open. Consequently, there will be no pressure.

During approach to top dead center (TDC), between compression and power strokes, there will be pressure. Consequently, it will push your thumb off of the hose, to allow air to escape. When air stops blowing out, it is fairly near (TDC) on the compression stroke. Move on to STEP FOUR.

Vacuum Pressure Gauge

Use a vacuum/pressure gauge. Hook up the gauge to your hose. Again turn the engine over by hand until you see pressure. Keep going until you see the pressure change to vacuum. Move on to STEP FOUR.

Use a compression tester. Again turn the engine over by hand, until you see pressure starting to build ( it won’t be much ). Move on to STEP FOUR.

Balloon

Other things I have seen are, putting a balloon or a finger from a latex glove over the hose. The balloon or finger will fill up, till it gets to (TDC) then it will suck back in.

STEP FOUR:

Now, remove the hose and place a long screwdriver, coat hanger or straw into the spark plug hole. Next, feel for the height of the piston.

Now there are times where you have to be dead on, but this covers most cases.

Piston Stop Gauge

A more accurate way to locate (TDC) is by using a piston stop tool. Screw the tool into the #1 spark plug hole by hand. Next, slowly rotate the crankshaft by hand, until the piston comes up against the stop.

Mark your balancer with a marker, and then slowly rotate the crankshaft by hand, in the opposite direction. Continue, until you come up against the stop again. Mark your balancer again. Measure the distance between the two marks and divide by two. As a result, this is your (TDC).

Conclusion

All things considered, setting an engine to top dead center, is a relatively straightforward procedure.

How to Find Top Dead Center

In this step by step guide, you will see two different methods for finding the top dead center of an engine. In the first method, we will focus on engines that have an easily accessible cylinder one spark plug hole; in the second method, we will focus on engines where the cylinder one spark plug hole is not easily accessible, such as with many four-cylinder or overhead cam style engines.

Method 1 of 2: Finding top dead center for engines with an easily accessible spark plug hole

Materials Needed

Step 1: Remove the spark plug from the number one cylinder. Remove the spark plug in the engine’s number one cylinder using your ratchet and spark plug socket.

Step 2: Locate the crankshaft pulley/harmonic balancer. Find your crankshaft pulley, also called the harmonic balancer. It is usually the largest pulley, often located in the center of the engine’s bottom end.

Look for the timing marks on the pulley and the marker with which to line them up, usually located on the engine’s block or front cover.

Step 3: Seal the spark plug hole. Have your helper put their finger over the top of the cylinder one spark plug hole, sealing it to the best of their ability. Continue to maintain the seal during Step 4.

Step 4: Turn the crankshaft pulley. Turn the crankshaft pulley by hand with a ratchet and socket. As you will be turning against the engine and all of its accessories, this may require a bit of effort.

If the engine does not turn at first, use a bit more force or try to turn it the opposite direction.

Continue to turn the crankshaft pulley until your helper can feel or hear air being pushed out of the cylinder. This indicates that the cylinder is on the compression stroke.

Continue to turn the crankshaft until the zero or top dead center mark on the pulley matches up with the pointer on the engine. For most engines, the zero or top dead center mark will be the first mark, or will be clearly marked in a different color or manner than the other marks on the pulley.

Step 5: Verify that the engine is in top dead center position. Once the top dead center timing mark is lined up with the marker on the engine, the motor should now be at top dead center.

To verify, shine the flashlight down into the spark plug hole. You should be able to see the top of the piston clearly near the top of the cylinder.

Method 2 of 2: Finding top dead center for overhead cam engines with inaccessible spark plug holes

Materials Needed

Step 1: Remove the spark plug from the number one cylinder. Remove the spark plug in the engine’s number one cylinder using your ratchet and spark plug socket.

Step 2: Locate the crankshaft pulley/harmonic balancer. Find your crankshaft pulley or harmonic balancer. It is usually the largest pulley, often located in the center of the engine’s bottom end, same as you did in method 1.

Then look for the timing marks on the pulley and the pointer with which to line them up, usually located on the engine’s block or front cover.

Step 3: Remove the engine valve cover. Most valve covers are secured using only a few ten millimeter bolts. Remove all of the bolts, taking care not to damage the gasket as you remove it, and pull the valve cover free.

Step 4: Identify the camshaft timing marks. Once the valve cover is removed, you should be able to see the camshaft, or camshafts, if it is a dual overhead cam engine.

Look for the camshaft timing marks located on the gears. They are usually clearly marked in the form of notches, pins or sometimes stamped words.

Step 5: Turn the crankshaft pulley. Turn the engine’s crankshaft pulley using a ratchet and socket until the timing marks on both the crankshaft pulley and the camshaft gears align to top dead center.

Usually the marks will align in a very specific manner when the engine reaches top dead center, such as pointing towards or opposite of each other when correctly aligned. Refer to the service manual for specifics on aligning your camshaft pulleys.

Once all of the timing marks are lined up correctly, the engine is at top dead center.

All things considered, setting an engine to top dead center is a relatively straightforward procedure. However, if you do not feel comfortable taking on this task, a professional mechanic, such as one from YourMechanic, will be able to provide this service.

Next Step

Schedule Top Dead Center (TDC) Sensor Replacement

The most popular service booked by readers of this article is Top Dead Center (TDC) Sensor Replacement. YourMechanic’s technicians bring the dealership to you by performing this job at your home or office 7-days a week between 7AM-9PM. We currently cover over 2,000 cities and have 100k+ 5-star reviews. LEARN MORE

top dead centre

Смотреть что такое «top dead centre» в других словарях:

top dead centre — noun (of a reciprocating engine or pump) the piston position at the beginning of the outstroke, ie when the crank pin is nearest to the cylinder (also inner dead centre) • • • Main Entry: ↑top … Useful english dictionary

Dead centre — For the lathe tool, see lathe center. In a reciprocating engine, the dead centre is the position of a piston in which it is farthest from, or nearest to, the crankshaft. The former is known as top dead centre (TDC) while the latter is known as… … Wikipedia

dead centre — /dɛd ˈsɛntə/ (say ded sentuh) noun 1. (in a reciprocating engine or pump) either of two positions of the crank in which the connecting rod has no power to turn it, occurring when the crank and connecting rod are in the same plane, at each end of… … Australian-English dictionary

inner dead centre — noun The piston position, when the crank pin is nearest to the centre, at the beginning of the outstroke of a reciprocating engine or pump (also top dead centre) • • • Main Entry: ↑inner … Useful english dictionary

dead centre — noun the position of a crank when it is in line with the connecting rod and not exerting torque • Syn: ↑dead center • Hypernyms: ↑position, ↑spatial relation * * * dead centre noun 1. In a reciprocating engine or pump, either of the positions, at … Useful english dictionary

Musgrave non-dead-centre engine — Park Street Mill engine in the Bolton Steam Museum … Wikipedia

centre — /ˈsɛntə / (say sentuh) noun 1. Geometry the middle point, as the point within a circle or sphere equidistant from all points of the circumference or surface, or the point within a regular polygon equidistant from the vertices. 2. a point, pivot,… … Australian-English dictionary

Top Gear (2002 TV series) — Top Gear Top Gear logo since 2002 Genre Motoring Directed by Brian Klein Presented … Wikipedia

Dead Can Dance — Dead Can … Wikipedia

Top Ryde City — is a major shopping centre currently being built in Ryde, in Sydney, Australia on the block bounded by Blaxland Road, Devlin Street, Pope Street and Turner Street.HistoryTop Ryde shopping centre originally opened in 1965 as one of the first… … Wikipedia

Centre Point — (sometimes rendered as Centrepoint ) is a substantial concrete and glass office building in central London, England, occupying 101 103 New Oxford Street, WC1, close to St Giles Circus and almost directly above Tottenham Court Road tube station.… … Wikipedia