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Encyclopedia > Sleeve valve
piston engine Bristol Perseus
piston engine Bristol Perseus

The sleeve valve is a type of valve mechanism for piston engines which have traditionally relied on the more common poppet valve. Image File history File linksMetadata Size of this preview: 800 × 600 pixelsFull resolution (1288 × 966 pixel, file size: 196 KB, MIME type: image/jpeg) This picture may have usage restriction Bristol Perseus sleeve valve radial engine Source: own picture File links The following pages on the English Wikipedia link to... Image File history File linksMetadata Size of this preview: 800 × 600 pixelsFull resolution (1288 × 966 pixel, file size: 196 KB, MIME type: image/jpeg) This picture may have usage restriction Bristol Perseus sleeve valve radial engine Source: own picture File links The following pages on the English Wikipedia link to... // These water valves are operated by handles. ... Components of a typical, four stroke cycle, DOHC piston engine. ... 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. ...

Contents

Introduction

A sleeve valve consists of one or more machined sleeves. It fits between the piston and the cylinder wall in the cylinder of an internal combustion engine where it rotates and/or slides, thus providing openings which align with the cylinder's inlet and exhaust ports at the appropriate stages in the engine's cycle.


Sleeve valves saw use in some pre-World War II luxury cars, sports cars, and the Willys-Knight car and light truck, and saw substantial use in aircraft engines of the 1940s, such as the Napier Sabre and Bristol Hercules and Centaurus, but they subsequently fell from use due to advances in poppet-valve technology (sodium cooling) and to their tendency to burn considerable amounts of lubricating oil or to seize due to lack of it. Combatants Allied powers: China France Great Britain Soviet Union United States and others Axis powers: Germany Italy Japan and others Commanders Chiang Kai-shek Charles de Gaulle Winston Churchill Joseph Stalin Franklin Roosevelt Adolf Hitler Benito Mussolini Hideki Tōjō Casualties Military dead: 17,000,000 Civilian dead: 33,000... A luxury car is a relatively expensive car. ... 1963 Jaguar E-Type, a classic sports car 1963 Chevrolet Corvette was based upon European sports cars A sports car is an automobile designed for performance driving. ... Willy on Wheels Willys Knight was an automobile produced by Willys. ... To meet Wikipedias quality standards, this article or section may require cleanup. ... The Sabre was a 24-cylinder sleeve valve piston aircraft engine designed by Major Frank Halford and built by Napier & Son during WWII. It was one of the most powerful piston aircraft engines in the world, especially for inline designs, developing over 3,500 horsepower (2,200 kW) in its... Bristol Hercules engine The Hercules was a 14_cylinder two_row radial aircraft engine produced by the Bristol Engine Company starting in 1939. ... Bristol Centaurus engine The Centaurus was the final development of Bristol Engine Companys series of sleeve valve radial aircraft engines, an 18-cylinder two-row design that eventually delivered over 3,000 hp (2. ...


At war's end the gas turbine replaced the single sleeve valve engine for military aircraft. Up to that point, the single sleeve valve won every contest against the poppet valve hands down in comparison of power to displacement. The difficulty of nitride hardening, then finish grinding the sleeve valve for truing the circularity, may be a factor of its lack of commercial applications. See below for further insights on the excessive oil consumption myth.


Case for sleeve valve

In a standard internal combustion engine, the poppet valves are opened by a shaped cam pressing on the top of the valve, while the valves are closed by a spring wrapped around the valve stem. For other uses, see CAM. Animation showing rotating cams and cam followers producing reciprocating motion. ...


The main problem with most valve systems is that as engine speed increases, the speed at which the valve moves also increases, increasing the loads involved due to the inertia of the valve, which has to be opened quickly, brought to a stop, then reversed in direction and closed and brought to a stop again. Large valves that allow good air-flow have considerable mass and require a strong spring to overcome the opening inertia. At some point, the valve spring reaches its resonance frequency, causing a compression wave to oscillate within the spring, which in turn causes it to become effectively shorter and therefore unable to properly close the valve. This "valve float" can eventually cause the valve to not close at all before the cam comes around to open it again and in some engines the rising piston may even collide with the valve. This article is about resonance in physics. ... Valve float is a condition which occurs when the valves on an internal combustion engine do not return to the fully closed position under high rpms due to valve springs incapable of overcoming the momentum of the valvetrain. ...


The desmodromic system as used by Ducati in all of its current motorcycle engines uses mechanical methods to close the valve, but this system requires precision engineering and is markedly more expensive than spring-closed valves. Desmodromic valves are those which are positively closed by a leverage system, rather than relying on the more conventional springs to close the valves. ... Ducati Motor Holding is an Italian motorcycle manufacturer. ...


Sleeve valve description

As its name implies, the sleeve valve is constructed as one or more sleeves that fit around the piston inside the cylinder wall. Ports (holes) in the side of the cylinder replace the more normal intake and exhaust ports on the head, and similar apertures in the sleeve(s) open and close the ports by being rotated into position. For the American composer, see Walter Piston. ...


In the engines pictured above each sleeve has teeth on its bottom which mesh with a gear turned (through other gears) by the crankschaft. These sleeves run in a pure circular fashion around the piston. In another variation the sleeve is driven by a crank which is driven (indirectly) by the crankshaft. In this version the sleeve runs circular as the in the Persius above but only a few degrees. Then up and down as well causing a circular movement opening the cylinder ports in the upper part of the movement. One motorcycle engine employed this method. Still another design involves a reduced height sleeve placed beneath the cylinder head. This has the advantage of being easier to construct, as it does not need to be strong enough to withstand the forces generated by a piston moving within it.


Advantages

The main advantages of the sleeve valve engine are:


1) an increase in volumetric efficiency due to very large port openings; Volumetric efficiency in internal combustion engine design refers to the efficiency with which the engine can move the charge into and out of the cylinders. ...


2) the combustion chamber formed with the sleeve at the top of its stroke is ideal for complete, and detonation-free, combustion of the charge, not having to contend with compromised chamber shape and hot exhaust (poppet) valve(s) (*see below) A combustion chamber is part of an engine in which fuel is burned. ...


No springs are involved in the sleeve valve system, therefore the power needed to operate the valve remains largely constant with the engine's RPM meaning that the system can be used at very high speeds with no penalty for doing so. In addition, the camshaft, pushrods, or rockers can be dispensed with, as the sleeve valves are generally driven by a single gear running directly off the driveshaft. For an aircraft engine this produced desirable reductions in weight and complexity. rpm or RPM may mean: revolutions per minute RPM Package Manager (originally called Red Hat Package Manager) RPM (movie) RPM (band), a Brazilian rock band RPM (magazine), a former Canadian music industry magazine In firearms, Rounds Per Minute: how many shots an automatic weapon can fire in one minute On...


Another principal advantage of the sleeve valve in early automotive applications (Knight engine) was longevity. Prior to the advent of leaded gasolines, poppet-valve engines typically required grinding the valves and valve seats after 20,000 to 30,000 miles of service. Sleeve valves did not suffer from the wear and recession caused by the repetitive impact of the poppet valve against its seat. Sleeve valves are also subjected to less intense heat buildup than is the poppet valve, owing to their greater contact with other large metal surfaces. As a Knight engine is used, carbon build-up helps to improve the sealing of the sleeves, thus the engines were said to "improve with use", in contrast to poppet-valve engines that lose compression and power as valves and valve stems/guides wear.


An additional advantage of the system is that the size of the ports can be readily controlled. This is of importance when an engine runs over a wide range of RPM, as the speed at which air can enter and exit the cylinder is defined by the size of the duct leading to the cylinder and varies according to the cube of the RPM. In other words, at higher RPM the engine typically requires larger ports that remain open for a greater proportion of the cycle, something that is fairly easy to arrange with sleeve valves, but difficult in a poppet valve system.


A major advantage is the single sleeve valve's laminar exhaust scavenging and vortex fuel mixture ignition. When the intake ports open, the fuel air mixture enters tangentially to the cylinder. This creates laminar exhaust scavenging, as opposed to turbulent poppet valve scavenging which mixes the exhaust - fresh air fuel mixture intake to a greater degree. A spinning fuel air mixture vortex is also created at TDC which greatly improves ignition.


A minor advantage includes the fact that the cylinder head is not required to house valves, therefore allowing the sparkplug(s) to be placed in the best possible location(s) for efficient ignition of the combustion mixture.

  • Note on main advantages: Most of the evaluation of these advantages was established during the 1920's by Sir Harry Ricardo, possibly the sleeve-valve engine's greatest advocate. He conceded however, that as fuels improved up to and during WWII, as well as with the advent of the sodium cooled exhaust valve in high output aero-engines, these advantages were significantly eroded.

Disadvantages

The sleeve valve has one major disadvantage, in that perfect sealing is difficult. In a poppet valve engine the piston possesses piston rings (often at least 3 and sometimes as many as 8) which form a seal with the cylinder bore, and during the "breaking in" period any imperfections in one are scraped into the other resulting in a good fit. This type of "breaking in" (known as "running-in" in the UK) is not possible on a sleeve valve engine however, because the piston and sleeve move in different directions and in some systems even rotate in relation to one another. In the 1940s this was not a major concern because the poppet valves of the time typically leaked appreciably more.


The oil consumption problem came from the Knight double sleeve valve. This problem was fixed with the single sleeve valve perfected by Bristol. At TDC, the single sleeve valve rotates in relation to the piston. This prevents boundary lubrication problems. You don't get piston ring ridge wear at TDC and BDC on the cylinder. The Hercules top end was rated at 50,000 hrs. (5,000?) at wide open throttle.


Modern usage

The sleeve valve has begun to make something of a comeback, due to modern materials and newer and dramatically better engineering tolerances and construction techniques which produce a sleeve valve that leaks very little oil. However, most advanced engine research is concentrated on entirely different designs of internal combustion engine such as the Wankel rotary-piston engine, as opposed to improvements to existing engines such as the sleeve valve. A lathe is a common tool used in machining. ... Wankel Engine in Deutsches Museum Munich, Germany The Wankel rotary engine is a type of internal combustion engine, invented by German engineer Felix Wankel, which uses a rotor instead of reciprocating pistons. ...


History

The sleeve valve principle was invented in 1903 by the American inventor Charles Yale Knight. Although he was initially unable to sell his Knight Engine in the US, a trip to Europe secured several luxury car firms as customers willing to pay his expensive premiums. He first patented the design in Britain in 1908. The Knight Engine was an internal combustion engine, designed by Charles Yale Knight (1868-1940), that used sleeve valves instead of the more common poppet valve construction. ... Year 1908 (MCMVIII) was a leap year starting on Wednesday (link will display the full calendar) of the Gregorian calendar (or a leap year starting on Tuesday of the 13-day-slower Julian calendar). ...


Among the companies using Knight's technology were Gabriel Voisin (in his Avions Voisin cars), Daimler (in their V-12 'Double Six', from 1909-1930), Panhard (1911-39), Mercedes (1909-24), Willys (as the Willys-Knight, plus the associated Falcon-Knight and Stearns-Knight), Mors, Peugeot, Argyll (Scotland), and Belgium's Minerva company, some thirty companies in all.[1] Itala also exprimented with sleeve valves. Henry Farman, left, and Gabriel Voisin. ... Avions Voisin was an advanced French luxury automobile marque by Gabriel Voisin. ... Daimler may refer to Gottlieb Daimler, German engineer and automobile inventor in the 1880s Daimler Motoren Gesellschaft, his Stuttgart-based company, maker of Mercedes vehicles since 1903, later merged into Daimler-Benz, maker of Mercedes-Benz vehicles (since 1926) DaimlerChrysler (1998), a part German, part American, part Japanese car maker... A Panhard-Levassor was the first automobile to be introduced in Japan, in 1898 Panhard & Levassor X18 1912 Panhard & Levassor 1914 Panhard & Levassor X31 1921 A 1920s Panhard Dyna Panhard X 86 4-Door Sedan 1952 Panhard repair manual cover showing PL 17 A VBL of the French Army Panhard... Mercedes may refer to: Things Mercedes-Benz, a German brand of automobiles and trucks Mercedes-Benz (song), by Janis Joplin Mercedes (calculator), an early 20th-century computing device Mercedes College, South Australia Places Mercedes, Buenos Aires, Argentina Mercedes, Paraná, Brazil Mercedes, Camarines Norte, Philippines Mercedes, Eastern Samar, Philippines Mercedes, Texas... 1920 Willys-Knight advertisement Willys (correctly pronounced WILL-iss, but Will-eez is more common), was the brand name used by the United States automobile company, Willys-Overland Motors, best known for its production of military and civilian Jeeps, during the twentieth century. ... In Roman mythology, Mors is the personification of death. ... Peugeot is a major French car brand, part of PSA Peugeot Citroën. ... Argyll, archaically Argyle (Airthir-Ghaidheal in Gaelic, translated as [the] East Gael, or [the] East Irish), sometimes called Argyllshire, is a traditional county of Scotland. ... 1928 Minerva that was owned by Gen. ... Itala Itala Itala was a exotic car manufacturer in Turin, Italy from 1904-1934, started by Matteo Ceirano and five partners in 1903. ...


Upon Knight's return to America he was able to get some firms to use his design; here his brand name was Silent Knight (1905-1907) — the selling point was that his engines were quieter than those with standard poppet valves. The best known of these were the F.B. Stearns Company of Cleveland, which sold a car named the Stearns-Knight, and the Willys firm which offered a car called the Willys-Knight, which was produced in far greater numbers than any other sleeve-valve car. The Silent Knight was a Medieval-set comic book series that was published by DC Comics. ... Also see: Stearns-Knight 1908 Stearns roadster F. B. Stearns and Company (later F.B. Stearns Company) was a manufacturer of luxury automobiles in Cleveland, Ohio marketed under the brand name Stearns and Stearns-Knight brand names. ... Stearns-Knight catalog image, taken outside the Cleveland Museum of Art Stearns-Knight was a luxury automobile produced in Cleveland, Ohio first by the F.B. Stearns Company from 1900 to 1925, and then under ownership by WillysOverland Company of Toledo, Ohio until 1929. ... 1920 Willys-Knight advertisement Willys (correctly pronounced WILL-iss, but Will-eez is more common), was the brand name used by the United States automobile company, Willys-Overland Motors, best known for its production of military and civilian Jeeps, during the twentieth century. ... Willy on Wheels Willys Knight was an automobile produced by Willys. ...


A number of sleeve valve aircraft engines were developed following a seminal 1927 research paper from the RAE by Harry Ricardo. This paper outlined the advantages of the sleeve valve, and suggested poppet valve engines would not be able to offer power outputs much beyond 1500 hp (1,100 kW). Napier and Bristol began the development of sleeve valve engines that would eventually result in two of the most powerful piston engines in the world, the Napier Sabre and Bristol Centaurus. Year 1927 (MCMXXVII) was a common year starting on Saturday (link will display full calendar) of the Gregorian calendar. ... This article needs cleanup. ... ira ira irsa ir air ira ira irs ira ira ira ira ira irea ira ira ira ira ira ira ira ira irs rias irsa k5tan ir4aq ira ira iora ira rika ira 9ria ira iras oira ir ri aria ria ria ira ira ira eia iea ieaiea iramieaneianieaie aieanimsnkwjijair... General characteristics Layout W-block inline Cooling water-cooled Cylinders 12 Valve type poppet Displacement 1462 in³ (25 l) Rotation rate 2050 rpm Power 500 hp Power 370 kW Weight 858 lb (290 kg) The Lion was a 12-cylinder W-block inline aircraft engine built by Napier & Son starting... Bristol Aeroplane Company logo The Bristol Aeroplane Company (formerly British and Colonial Aeroplane Company) was a major British aircraft company which, in 1959, merged with several major British aircraft companies, to become the British Aircraft Corporation and later still part of British Aerospace, now BAE Systems. ... The Sabre was a 24-cylinder sleeve valve piston aircraft engine designed by Major Frank Halford and built by Napier & Son during WWII. It was one of the most powerful piston aircraft engines in the world, especially for inline designs, developing over 3,500 horsepower (2,200 kW) in its... Bristol Centaurus engine The Centaurus was the final development of Bristol Engine Companys series of sleeve valve radial aircraft engines, an 18-cylinder two-row design that eventually delivered over 3,000 hp (2. ...


A noteworthy sleeve-valve engine (that never reached production) was the Rolls-Royce Crecy, a 60 degree, V-12 two-stroke direct injected supercharge-scavenged aero-engine of 26 litres capacity. It achieved a very high specific output - in single or V-twin test-bench form (E65) in 1945 it produced the equivalent of 5,000 HP (192 BHP/Litre), although the full V12 would probably have been initially type rated circa 2,500~3,000 HP. The Rolls-Royce Crecy was a 2-stroke 90 degree V12 liquid cooled aero engine of 26. ...


Following World War II the sleeve valve disappeared from use, as the previous problems with sealing and wear on poppet valves had been remedied by the use of better materials, and the inertia problems with the use of large valves were reduced by using several smaller valves instead, giving increased flow area and reduced mass. Combatants Allied powers: China France Great Britain Soviet Union United States and others Axis powers: Germany Italy Japan and others Commanders Chiang Kai-shek Charles de Gaulle Winston Churchill Joseph Stalin Franklin Roosevelt Adolf Hitler Benito Mussolini Hideki Tōjō Casualties Military dead: 17,000,000 Civilian dead: 33,000... This article is about inertia as it applies to local motion. ...


Steam engine

Sleeve valves have occasionally been used on steam engines, for example the SR Leader Class. The Southern Railway’s Leader Class was a class of experimental 0-6-6-0 articulated locomotive, produced to the design of the innovative engineer Oliver Bulleid. ...


See also


  Results from FactBites:
 
Sleeve valve - Wikipedia, the free encyclopedia (1448 words)
The sleeve valve is a type of valve for piston engines that has a number of advantages over the more common poppet valve, used in most engines, as well as disadvantages that have precluded its widespread adoption to date.
In a normal engine using poppet valves, the valves are opened by the camshaft pushing down on the top of the valve, sometimes via a long pushrod and rocker taking the power from the crankshaft area to the top of the cylinders.
Otherwise a single sleeve is operated by a crank driven from the crankshaft, the sleeve moves in a circular path opening the cylinder ports in upper part of the circle.
  More results at FactBites »

 
 

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