For other uses see Piston (disambiguation).

A piston is a component of reciprocating engines, pumps and gas compressors. A reciprocating engine, also often known as a piston engine, is a Heat engine that uses one or more reciprocating Pistons to convert For information on Wikipedia project-related discussions see WikipediaVillage pump. A gas compressor is a mechanical device that increases the Pressure of a Gas by reducing its Volume. It is located in a cylinder and is made gas-tight by piston rings. A cylinder is the central working part of a Reciprocating engine, the space in which a Piston travels A piston ring is an open-ended ring that fits into a groove on the outer diameter of a Piston in a Reciprocating engine such as an Internal combustion In an engine, its purpose is to transfer force from expanding gas in the cylinder to the crankshaft via a piston rod and/or connecting rod. The crankshaft, sometimes casually abbreviated to crank, is the part of an Engine which translates reciprocating Linear In a Piston engine, a piston rod joins a Piston to a Connecting rod. In a reciprocating Piston engine, the connecting rod or conrod connects the Piston to the crank or Crankshaft. In a pump, the function is reversed and force is transferred from the crankshaft to the piston for the purpose of compressing or ejecting the fluid in the cylinder. FLUID ( F ast L ight '''U'''ser '''I'''nterface D esigner is a graphical editor that is used to produce FLTK Source code In some engines, the piston also acts as a valve by covering and uncovering ports in the cylinder wall. For other uses see Valve (disambiguation. For the electronic component see Thermionic valve. Cylinder head porting refers to the process of modifying the intake and exhaust ports of an Internal combustion engine to improve the quality and quantity of the gas flow

Piston engines

Main article: Reciprocating engine

Internal combustion engines

Components of a typical, four stroke cycle, DOHC piston engine. A reciprocating engine, also often known as a piston engine, is a Heat engine that uses one or more reciprocating Pistons to convert Today Internal combustion engines in cars, Trucks motorcycles aircraft construction machinery and many others most commonly use a four-stroke cycle. (E) Exhaust camshaft, (I) Intake camshaft, (S) Spark plug, (V) Valves, (P) Piston, (R) Connecting rod, (C) Crankshaft, (W) Water jacket for coolant flow. The camshaft is an apparatus often used in Piston engines to operate Poppet valves It consists of a cylindrical rod running the length of the Cylinder bank A spark plug (also very rarely nowadays in British English: a sparking plug) is an electrical device that fits into the Cylinder A poppet valve is a Valve consisting of a hole usually round or oval and a tapered plug usually a disk shape on the end of a shaft also called a valve stem In a reciprocating Piston engine, the connecting rod or conrod connects the Piston to the crank or Crankshaft. The crankshaft, sometimes casually abbreviated to crank, is the part of an Engine which translates reciprocating Linear

There are two ways that an internal combustion piston engine can transform combustion into motive power. The internal combustion engine is an engine in which the Combustion of Fuel and an Oxidizer (typically air occurs in a confined space called a These are the two-stroke cycle and the four-stroke cycle. The two-stroke Internal combustion engine differs from the more common Four-stroke engine by completing the same four processes (intake compression combustion exhaust Today Internal combustion engines in cars, Trucks motorcycles aircraft construction machinery and many others most commonly use a four-stroke cycle. A single cylinder two-stroke engine produces power every crankshaft revolution, while a single cylinder four-stroke engine produces power once every two revolutions. Older designs of small two-stroke engines produced more pollution than four stroke engines. However, modern two-stroke designs, like the Vespa ET2 Injection utilise fuel-injection and are as clean as four-strokes. Fuel injection is a system for mixing fuel with air in an Internal combustion engine. Large diesel two-stroke engines, as used in ships and locomotives, have always used fuel injection and produce low emissions. One of the biggest internal combustion engines in the world, the Wärtsilä-Sulzer RTA96-C is a two-stroke; it is bigger than most two-story houses, has pistons nearly 1 metre in diameter and is one of the most efficient mobile engines in existence. The Wärtsilä RT-flex96C Turbocharged Two-stroke Diesel engine is currently considered the largest Reciprocating engine in the world The metre or meter is a unit of Length. It is the basic unit of Length in the Metric system and in the International Geometry, a diameter of a Circle is any straight Line segment that passes through the center of the circle and whose Endpoints are on the In theory, a four-stroke engine has to be larger than a two-stroke engine to produce an equivalent amount of power. Two-stroke engines are becoming less common in developed countries these days, mainly due to manufacturer reluctance to invest in reducing two-stroke emissions. Traditionally, two-stroke engines were reputed to need more maintenance (despite exceptions like the Ricardo Dolphin engine, and the Twingle engines of the Trojan car and the Puch 250 motorcycle). Sir Harry Ricardo ( 26 January 1885 – 18 May 1974) was one of the foremost engine designers and researchers in the early years of the development The Twingle engine is a Two-stroke engine usually of small-capacity and usually Gasoline -fueled Trojan was a British Automobile manufacturer; the eponymous Marque thereof was produced between 1914 and 1974 Puch was a Manufacturing company located in Graz, Austria. The company was founded in 1889 by the industrialist Johann Puch and produced Even though the simplest two-stroke engines have fewer moving parts, they could wear out faster than four-stroke engines. However fuel-injected two-strokes achieve better engine lubrication, and cooling and reliability should improve considerably.

Gallery

A piston and its connecting rod.

CAD drawing of crankshaft and pistons. The crankshaft, sometimes casually abbreviated to crank, is the part of an Engine which translates reciprocating Linear

Large pistons (over 0. 5 m incl. connecting rod).

Simplified piston animation.

Steam engines

Steam engines are usually double-acting (i. A steam engine is a Heat engine that performs Mechanical work using Steam as its Working fluid. e. steam pressure acts alternately on each side of the piston) and the admission and release of steam is controlled by slide valves, piston valves or poppet valves. The D Slide Valve was a form of Rectilinear slide valve for use in rotative Steam engines invented by William Murdoch and patented in 1799. A piston valve is a device used to control the motion of a Fluid along a tube or pipe by means of the Linear motion of a Piston within A poppet valve is a Valve consisting of a hole usually round or oval and a tapered plug usually a disk shape on the end of a shaft also called a valve stem

Air cannons

There are two special type of pistons used in air cannons: close tolerance piston and double piston. While in close tolerance piston, O-rings are used as valve but in double piston, O-rings are not used.

There are some features of close tolerance piston mentioned below:

1. Piston can swell and stick.
2. Fits tightly in the cylinder.
3. Tight Tolerance fit.
4. Properties alter due to atmospheric change.
5. Backlash may such,some of the bin material into the valve which also can cause the piston to stick.

Common features of double piston:

1. Cannot swell and stick.
2. Fits loosely in the cylinder.
3. No tight tolerance fit.
4. Properties are not altered due to atmospheric change.
5. Even if foreign material enters the valve,the double piston does not stick.

See also

• Piston ring
• Air gun
• Flamethrower
• Fruit press
• Hydraulic cylinder
• Knurling
• Slide whistle
• Wankel engine (an internal combustion engine with a rotary 'piston')
• Steam locomotive components

References

External links

• Piston highlight: Hypervideo of construction and operation of four cylinder internal combustion engine courtesy of Ford Motor Company