What Cylinders Are On Chainsaws
For more than a hundred years in the world, the main power unit in all wheeled vehicles has been a piston internal combustion engine. Having appeared at the beginning of the XX century and replacing a steam engine, ICE in the XXI century remains the most profitable type of engine in terms of economy and efficiency. Let’s take a closer look at how this type of ICE is arranged, how it works, find out what other piston engines are.
Definition, features of ICE
In the process of development of science and technology, the design of the internal combustion engine was constantly improved. Engines were able to prove their effectiveness. So there were piston internal combustion engines and, as a subspecies, carburetor and injection engines. Diesel engines, rotary piston and gas turbine units can be distinguished.
A traditional piston engine is equipped with an internal combustion chamber. This is the cylinder inside the engine block. When burning fuel, energy is released, which is then converted into mechanical movement of the crankshaft. Due to the translational movement of the pistons, which act on the system of connecting rods and crankshaft, the rotation of the flywheel is obtained. You can familiarize yourself with the design in the relevant GOST piston internal combustion engine.
The carburetor internal combustion engine is characterized in that the working mixture of fuel and air is prepared in a special device. a carburetor. The mixture is injected into the cylinders by vacuum. Further, it is ignited thanks to the spark plug.
Injector ICE has a more modern design. Here, instead of the traditional mechanical device, electronic nozzles are available in the power system. They are responsible for injecting exact portions of fuel directly into the engine cylinders.
A diesel piston internal combustion engine has certain structural and fundamental differences from gasoline ICEs.
If a spark from a candle is used in a gasoline unit for ignition, then a different principle works in diesel engines and there are no candles except glow. Diesel fuel enters the cylinders through nozzles, mixes with air, and then the whole mixture is compressed, as a result of which it is heated to the combustion temperature.
The rotary piston engine is significantly different from traditional internal combustion engines. Gases act on special parts and elements. So, under the influence of gases, the movable rotor moves in a special chamber in the form of a figure eight. The camera performs the functions of pistons, timing and crankshaft. The camera has the shape of a figure of eight.
In gas turbine internal combustion engines, thermal energy is converted into mechanical energy due to the rotation of a special rotor with special blades. This rotor drives the turbine shaft.
Special piston and combined internal combustion engines (which are gas turbine engines and rotary engines) can be safely entered in the red book. Today, the rotary piston engine is made only by the Japanese Mazda. Crysler once released an experimental series of gas turbine ICEs, but this was in the 60s and more to this issue, none of the automakers have returned to this day.
Video: What Cylinders Are On Chainsaws
In the Soviet Union, gas turbine ICEs were installed on tanks and landing ships, however, it was further decided there to abandon units of this design.
The engine is a single mechanism. It consists of a cylinder block, parts of a crank mechanism, a timing mechanism, an injection and exhaust system.
A combustion chamber is located inside the cylinder block, where the fuel-air mixture is directly ignited, and the combustion products drive the pistons. By means of a crank mechanism, the energy of fuel combustion is transmitted to the crankshaft. The timing mechanism is necessary to ensure timely opening and closing of the intake and exhaust valves.
When the engine is started, a mixture of fuel and air is injected into the cylinders through the inlet valve and is ignited by a spark in the spark plug generated by the ignition system. During combustion, gases are formed. When thermal expansion occurs, due to excess pressure, the piston begins to move, thereby rotating the crankshaft.
The operation of piston engines is cyclical. In the cycle of a reciprocating internal combustion engine, there can be from two to four cycles. Cycles during the operation of the motor are repeated several hundred times in one minute. So the crankshaft can rotate continuously.
Two stroke ICE
When the engine starts, the piston is driven by rotation of the crankshaft. When the piston reaches the bottom dead center position and begins to move up, the fuel-air mixture will be supplied to the cylinder.
When moving up, the piston will begin to compress the mixture. When the piston reaches its upper position, a spark will be generated. The fuel-air mixture will ignite. When expanding, the gases will push the piston down.
At this point, the exhaust valve opens, through which the combustion products can exit the chamber. Then again reaching the bottom dead center, the piston will begin its path at TDC. All these processes take place in one revolution of the crankshaft.
When the piston starts a new movement, the inlet valve opens and a new portion of the air-fuel mixture replaces the exhaust gases. The whole process will start again. A two-stroke piston internal combustion engine performs fewer movements than a four-stroke one. Friction losses are reduced, but more heat is released.
The timing mechanism is replaced by a piston. During the movement of the piston, the inlet and outlet openings in the cylinder block open and close. Compared with a four-stroke power unit, gas exchange in a two-stroke engine is a major drawback. At the time of exhaust gas, efficiency and power are lost.
Despite this drawback of two-stroke piston internal combustion engines, they are used in mopeds, scooters, as boat engines, in chainsaws.
Four stroke internal combustion engine
The four-stroke internal combustion engine lacks the two-stroke engine. Such motors are installed on most cars and other equipment. The intake and exhaust of exhaust gases is a separate process, and it is not combined with compression, although a piston internal combustion engine works from ignition of the mixture. The motor is synchronized by a gas distribution mechanism. the valves open and close synchronously with the crankshaft speed. The intake of the fuel mixture is carried out only after a complete exit of exhaust gases.
The advantages of ICE
You should start with the most popular engines. in-line four-cylinder units. Among the advantages are compactness, low weight, one cylinder head, high maintainability.
Among all types of internal combustion engines, opposer engines can also be distinguished. They are not very popular because of the more complex design. They are mainly used on racing cars. Among the advantages. excellent primary and secondary balancing, and hence the soft work. The crankshaft is less loaded. As a result, minor power losses. The engine has a low center of gravity, and the car is better driven.
Inline six-cylinder engines are perfectly balanced, and the unit itself works very smoothly. Despite the large number of cylinders, the production price is not very high. It is also possible to highlight maintainability.
The main disadvantage of reciprocating internal combustion engines is still not toxicity and noise, but poor efficiency. In ICE, only 20% of the energy is spent on the actual mechanical work. Everything else is spent on heating and other processes. Engines also release harmful substances into the atmosphere such as nitrogen oxides, carbon monoxide, and various aldehydes.