What is the duty cycle of an engine? Top dead center, bottom dead center?

The duty cycle of an engine refers to air intake, compression, combustion (expansion), and exhaust. It's what we often call a four-stroke.

Top dead center is the position where the piston moves in the cylinder and the top of the piston reaches the highest point, which is called top dead center. That is, the top of the piston is the farthest point from the center of rotation of the crankshaft.

The bottom dead center is the position where the piston moves in the cylinder and its top reaches the lowest point, which is called the bottom dead center. That is, the top of the piston is closest to the center of rotation of the crankshaft.

Engine maintenance precautions.

Use lubricants of the appropriate quality grade. The selection standard shall not be lower than the requirements specified by the manufacturer, and pay attention to the quality of lubricating oil purchase.

If you are running low on fuel, you should add it in time. There is an electric fuel transfer pump in the tank that delivers fuel to the engine. When the motor is working, it heats up, and when it sinks in the fuel, the heat is cooled by the surrounding fuel, and it can run for a long time.

However, when the fuel in the tank is seriously insufficient, the fuel pump is exposed to the air, and the temperature of the motor gradually increases, which is easy to burn out the motor. Therefore, when the fuel gauge pointer reaches the warning zone, it is necessary to add fuel in time.

The position at which the highest point of the piston is at a minimum distance from the center of rotation of the crankshaft, usually the lowest position of the piston, is called the bottom dead center.

Summary. Hello dear, the engine from the top dead center to the bottom dead center refers to the top dead center and bottom dead center of the engine, and the top dead center and bottom dead center of the engine refer to the highest and lowest points of the piston inside the engine to do work up and down.

Hello pro-pants macro, the engine from the top dead center to the bottom dead center refers to the top dead center and the bottom dead center of the engine to start the empty pure volt machine refers to the highest point and lowest point of the piston inside the engine to do work up and down.

By several bridges connected to the piston on the crankshaft, all up and down movement is generated, every time the piston does the up and down movement, the search simply says that the engine is completed once, inhalation, compression, deflagration, discharge. Generate power to make the vehicle move.

The top dead center is the position where the piston moves forward in the cylinder, and the top of the piston reaches the highest point, which is called the top dead center. That is, the top of the piston is the farthest point from the center of rotation of the crankshaft. The bottom dead center is the position where the piston moves in the cylinder and the top of the piston reaches the lowest point, which is called the bottom stop roll inventory.

That is, the top of the piston is closest to the center of rotation of the crankshaft.

1) Top dead center: The piston moves in the cylinder, and the top of the piston reaches the position at the highest point, which is called the top dead center. That is, the top of the piston is the farthest point from the center of rotation of the crankshaft.

2) Bottom dead center: The position where the piston moves in the cylinder and the top of the piston reaches the lowest point is called the bottom dead center. That is, the top of the piston is closest to the center of rotation of the crankshaft.

3) Duty cycle: Each time the internal combustion engine completes a work process of suction, compression, work and exhaust, it is called a working cycle.

Supplement: 3) Piston stroke: The piston moves in the cylinder, and the distance between its upper and lower dead centers is called piston stroke. It is denoted by s.

4) Crank radius: the distance from the axis line of the crank connecting rod journal to the axis line of the main journal, which is called the crankshaft radius. Denoted by r. The magnitude of the piston stroke depends on the radius of the crankshaft, and the relationship is as follows: the piston stroke S is equal to 2 times the radius of the crankshaft r, i.e. s = 2r.

5) Combustion chamber volume: When the piston is at the top dead center, the volume between the piston top and the cylinder head is called the combustion chamber volume. Represented by VC.

6) Total cylinder volume: When the piston is at the bottom dead center, the volume of the space above the piston top is called the total cylinder volume. It is denoted by va.

7) Cylinder working volume: The space volume swept by the piston when the piston moves from the top dead center to the bottom dead center or has the bottom dead center to move to the top dead center, which is called the cylinder working volume. Expressed by VH.

8) Compression ratio: the ratio of the total volume of the cylinder to the volume of the combustion chamber, which is called the compression ratio.

9) Internal combustion engine displacement: The sum of the working volumes of each cylinder of a multi-cylinder engine is called displacement. Represented by VL. That is, vl=i*vh, i is the number of cylinders.

10) Duty cycle: Each time the internal combustion engine completes a work process of suction, compression, work and exhaust, it is called a working cycle.

11) Two-stroke internal combustion engine: An internal combustion engine that completes a working cycle with each revolution of the crankshaft.

12) Four-stroke internal combustion engine: An internal combustion engine that completes a working cycle every two revolutions of the crankshaft.

13) Working condition: The working state of the internal combustion engine at a certain time is called the working condition. Generally, it is expressed in terms of the speed and load of the internal combustion engine.

Top dead center: In automobile and motorcycle gasoline engines, the position of the piston top at the maximum distance from the center of the crankshaft is called top dead center.

When the piston moves in a reciprocating linear motion in the cylinder, when the piston moves upwards to the highest position, that is, the extreme position where the top of the piston is farthest from the center of rotation of the crankshaft, it is called the top dead center.

In the engine, the piston moves up and down in the cylinder to complete the four strokes of suction, compression, work and exhaust. The scale when the piston moves to the top of the cylinder is the top dead center. (in compression and exhaust strokes).

For example, the top dead center of a cylinder, the position of the crank used by the piston lock of a cylinder is level with the centerline of the cylinder, and the piston position is the top of the cylinder. Before the start of the intake stroke, the end of the exhaust stroke and the end of the compression stroke are all located at the top dead center, which also becomes the top dead center, that is, it can no longer run up and down, the highest point.

This problem is not easy to express clearly, the timing mark of the camshaft to the bottom is that the piston moves to the top dead center, that is, the piston moves to the top of the cylinder.

LZ is good! Top dead center refers to the movement of the piston to the very top of the cylinder! Where the top of the piston goes! Thank you! Good luck to LZ in the end!

The position of the piston top at the maximum distance from the center of the crankshaft is called the top dead center.

The piston compresses the position of the mixture to the end.

The crankshaft turns, the piston does not move! Ah right?