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71-396: Single overhead camshaft (SOHC) engines have one camshaft per bank of cylinders . Dual overhead camshaft (DOHC, also known as "twin-cam") engines have two camshafts per bank. The first production car to use a DOHC engine was built in 1910. Use of DOHC engines slowly increased from the 1940s, leading to many automobiles by the early 2000s using DOHC engines. In an OHC engine, the camshaft

142-400: A flat-plane crank , whereby the throws are spaced 180° apart, which essentially results in two inline-four engines sharing a common crankcase. Flat-plane engines are usually able to operate at higher RPM, however they have higher second-order vibrations, so they are better suited to racing car engines. For some engines it is necessary to provide counterweights for the reciprocating mass of

213-474: A waterwheel fed by a mill race powering via a gear train two frame saws which cut blocks by the way of some kind of connecting rods and cranks. The crank and connecting rod mechanisms of the other two archaeologically attested sawmills worked without a gear train. A Roman iron crank dating to the 2nd century AD was excavated in Augusta Raurica , Switzerland . The crank-operated Roman mill

284-412: A Dutch farmer and windmill owner by the name Cornelis Corneliszoon van Uitgeest in 1592. His wind-powered sawmill used a crankshaft to convert a windmill's circular motion into a back-and-forward motion powering the saw. Corneliszoon was granted a patent for his crankshaft in 1597. From the 16th century onwards, evidence of cranks and connecting rods integrated into machine design becomes abundant in

355-475: A bar of high quality vacuum remelted steel . Though the fiber flow (local inhomogeneities of the material's chemical composition generated during casting) does not follow the shape of the crankshaft (which is undesirable), this is usually not a problem since higher quality steels, which normally are difficult to forge, can be used. Per unit, these crankshafts tend to be expensive due to the large amount of material that must be removed with lathes and milling machines,

426-668: A crank as a part of its mechanism. The crank was used to manually introduce dates. Evidence for the crank combined with a connecting rod, appears in the Ancient Greek Hierapolis mill , dating to the 3rd century AD under the Roman Empire; they are also found in stone sawmills in Roman Syria and Ephesus , Greek Ionia under Rome, dating to the 6th century. The pediment of the Hierapolis mill shows

497-520: A crankshaft, five centuries before the earliest known European description of a crankshaft. However, the automatic crank mechanism described by the Banū Mūsā would not have allowed a full rotation, but only a small modification was required to convert it to a crankshaft. In the Artuqid Sultanate , Arab engineer Ismail al-Jazari (1136–1206) described a crank and connecting rod system in

568-555: A flat engine. A V engine or flat engine requires four camshafts to function as a DOHC engine, since having two camshafts in total would result in only a single camshaft per cylinder bank for these engine layouts. Some V engines with four camshafts have been marketed as "quad-cam" engines, however technically "quad-cam" would require four camshafts per cylinder bank (i.e. eight camshafts in total), therefore these engines are merely dual overhead camshaft engines. Many DOHC engines have four valves per cylinder. The camshaft usually operates

639-430: A late antique original. Cranks used to turn wheels are also depicted or described in various works dating from the tenth to thirteenth centuries. The first depictions of the compound crank in the carpenter's brace appear between 1420 and 1430 in northern European artwork. The rapid adoption of the compound crank can be traced in the works of an unknown German engineer writing on the state of military technology during

710-404: A narrow V angle which allows a single cylinder block and cylinder head . These engines use a single cylinder head so are technically a straight engine with the name "VR" coming from the combination of German words “Verkürzt” and “Reihenmotor” meaning “shortened inline engine”. Flat engines (also known as "horizontally-opposed" engines) have the cylinders arranged in two banks on either side of

781-498: A rotating machine for two of his water-raising machines, which include both crank and shaft mechanisms. The Italian physician Guido da Vigevano ( c.  1280  – c.  1349 ), planning for a new Crusade , made illustrations for a paddle boat and war carriages that were propelled by manually turned compound cranks and gear wheels, identified as an early crankshaft prototype by Lynn Townsend White . Crankshafts were described by Leonardo da Vinci (1452–1519) and

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852-811: A series of six-cylinder engines which culminated in the Mercedes D.III . Rolls-Royce reversed-engineered the Mercedes cylinder head design based on a racing car left in England at the beginning of the war, leading to the Rolls-Royce Eagle V12 engine. Other SOHC designs included the Spanish Hispano-Suiza 8 V8 engine (with a fully enclosed-drivetrain), the American Liberty L-12 V12 engine, which closely followed

923-477: A similar principle applies to balance shafts , which are occasionally used. Crankshafts can be created from a steel bar using roll forging . Today, manufacturers tend to favour the use of forged crankshafts due to their lighter weight, more compact dimensions and better inherent damping. With forged crankshafts, vanadium micro-alloyed steels are mainly used as these steels can be air-cooled after reaching high strengths without additional heat treatment, except for

994-430: A single crankshaft. Boxer engines are a subtype of flat engines where opposing pistons move in and out in tandem. Types of flat engines include: W engines have the cylinders in a configuration in which the cylinder banks resemble the letter W, in the same way those of a V engine resemble the letter V. Types of W engines include: W engines using twin "VR" engine banks are technically a V8 engine. These engine banks use

1065-406: A single cylinder head so are technically a straight bank with the name "VR" coming from the combination of German words “Verkürzt” and “Reihenmotor” meaning “shortened inline engine”. Radial engines have cylinders mounted radially around a central crankcase. Rotary engines have a similar configuration, except that the crankshaft is fixed and the cylinders rotate around it. (This is different from

1136-553: A single power source by one connecting-rod, an idea also taken up by his compatriot Italian painter Francesco di Giorgio . The crank had become common in Europe by the early 15th century, as seen in the works of the military engineer Konrad Kyeser (1366–after 1405). Devices depicted in Kyeser's Bellifortis include cranked windlasses for spanning siege crossbows, cranked chain of buckets for water-lifting and cranks fitted to

1207-544: A small modification would have been required to convert it to a crankshaft. Al-Jazari (1136–1206) described a crank and connecting rod system in a rotating machine in two of his water-raising machines. His twin-cylinder pump incorporated a crankshaft. A crank is later also described in an early 15th century Arabic manuscript of Hero of Alexandria 's Mechanics . The first rotary hand mills, or rotary querns, appeared in Spain (600 BC – 500 BC), before they spread to

1278-497: A wheel of bells. Kyeser also equipped the Archimedes' screws for water-raising with a crank handle, an innovation which subsequently replaced the ancient practice of working the pipe by treading. Pisanello painted a piston-pump driven by a water-wheel and operated by two simple cranks and two connecting-rods. The 15th century also saw the introduction of cranked rack-and-pinion devices, called cranequins, which were fitted to

1349-707: A Δ when viewed along the axis of the main-shaft. An example of this type of layout is the Napier Deltic . Wankel engines (sometimes called 'rotary engines') can be classified based on the number of rotors present. Most production Wankel engines have two rotors, however engines with one, three and four rotors have also been produced. Wankel engines can also be classified based on whether they are naturally aspirated or turbocharged . Most Wankel engines are fueled by petrol, however prototype engines running on diesel and hydrogen have been trialed. Gas turbine engines— mostly used for aircraft— are usually separated into

1420-522: Is dated to the late 2nd century. Water-powered marble saws in Germany were mentioned by the late 4th century poet Ausonius ; about the same time, these mill types seem also to be indicated by Greek Saint Gregory of Nyssa from Anatolia . A rotary grindstone operated by a crank handle is shown in the Carolingian manuscript Utrecht Psalter ; the pen drawing of around 830 goes back to

1491-504: Is essentially two V engines joined by a common crankshaft. A majority of these were existing V-12 engines converted into an X-24 configuration. The Swashplate engine with the K-Cycle engine is where pairs of pistons are in an opposed configuration sharing a cylinder and combustion chamber. A Delta engine has three (or its multiple) cylinders having opposing pistons, aligned in three separate planes or 'banks', so that they appear to be in

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1562-409: Is located at the top of the engine, above the combustion chamber . This contrasts the earlier overhead valve engine (OHV) and flathead engine configurations, where the camshaft is located down in the engine block . The valves in both OHC and OHV engines are located above the combustion chamber; however an OHV engine requires pushrods and rocker arms to transfer the motion from the camshaft up to

1633-456: Is more complex in an OHC engine, such as the 4-chain valvetrain of the Audi 3.2 or the 2 meter chain on Ford cammers. Another disadvantage of OHC engines is that during engine repairs where the removal of the cylinder head is required, the camshaft engine timing needs to be reset. In addition, an OHC engine has a large cylinder head to accommodate the camshaft or an extra set of valves to increase

1704-403: Is often attached to one end of the crankshaft, in order to smoothen the power delivery and reduce vibration. A crankshaft is subjected to enormous stresses, in some cases more than 8.6 tonnes (19,000 pounds) per cylinder. Crankshafts for single-cylinder engines are usually a simpler design than for engines with multiple cylinders. The crankshaft is able to rotate in the engine block due to

1775-527: Is possible. The first known automotive application of timing belts to drive overhead camshafts was the 1953 Devin-Panhard racing specials built for the SCCA H-modified racing series in the United States. These engines were based on Panhard OHV flat-twin engines, which were converted to SOHC engines using components from Norton motorcycle engines. The first production car to use a timing belt

1846-400: Is similar to a flat engine in that pairs of pistons are co-axial but rather than sharing a crankshaft, instead share a single combustion chamber per pair of pistons. The crankshaft configuration varies amongst opposed-engine designs. One layout has a flat/boxer engine at its center and adds an additional opposed-piston to each end so there are two pistons per cylinder on each side. An X engine

1917-523: The Allied and Central Powers ; specifically those of the German Empire 's Luftstreitkräfte air forces, sought to quickly apply the overhead camshaft technology of motor racing engines to military aircraft engines. The SOHC engine from the Mercedes 18/100 GP car (which won the 1914 French Grand Prix) became the starting point for both Mercedes' and Rolls-Royce's aircraft engines. Mercedes created

1988-623: The Wankel engine configuration described below.) Radial and rotary engine designs were widely used in early aircraft engines . U engines consist of two separate straight engines (complete with separate crankshafts) joined by gears or chains. Most U engines have four cylinders (i.e. two straight-two engines combined), such as square four engines and tandem twin engines . Similar to U engines, H engines consist of two separate flat engines joined by gears or chains. H engines have been produced with between 4 and 24 cylinders. An opposed-piston engine

2059-399: The crossbow 's stock as a means of exerting even more force while spanning the missile weapon. In the textile industry, cranked reels for winding skeins of yarn were introduced. The Luttrell Psalter , dating to around 1340, describes a grindstone which was rotated by two cranks, one at each end of its axle; the geared hand-mill, operated either with one or two cranks, appeared later in

2130-444: The cylinders in lines parallel to the crankshaft . It is called a straight engine (or 'inline engine') when the cylinders are arranged in a single line. Where the cylinders are arranged in two or more lines (such as in V engines or flat engines ), each line of cylinders is referred to as a 'cylinder bank'. The angle between cylinder banks is called the 'bank angle'. Engines with multiple banks are shorter than straight engines of

2201-458: The volumetric efficiency , so that with the same displacement as an OHV engine, the OHC engine will end up being the physically larger of the two mostly due to the enlarged cylinder head. The other main advantage of OHC engines is that there is greater flexibility to optimise the size, location and shape of the intake and exhaust ports, since there are no pushrods that need to be avoided. This improves

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2272-429: The 'main bearings '. Since the crankshaft is subject to large horizontal and torsional forces from each cylinder, these main bearings are located at various points along the crankshaft, rather than just one at each end. The number of main bearings is determined based on the overall load factor and the maximum engine speed. Crankshafts in diesel engines often use a main bearing between every cylinder and at both ends of

2343-552: The 15th century. Around 1480, the early medieval rotary grindstone was improved with a treadle and crank mechanism. Cranks mounted on push-carts first appear in a German engraving of 1589. In 9th century Abbasid Baghdad , automatically operated cranks appear in several of the hydraulic devices described by the Banū Mūsā brothers in the Book of Ingenious Devices . These automatically operated cranks appear in several devices, two of which contain an action which approximates to that of

2414-422: The 1925-1948 Velocette K series , the 1931-1957 Norton International and the 1947-1962 Norton Manx . In more recent times, the 1950-1974 Ducati Single , 1973-1980 Ducati L-twin engine , 1999-2007 Kawasaki W650 and 2011-2016 Kawasaki W800 motorcycle engines have used bevel shafts. The Crosley four cylinder was the last automotive engine to use the shaft tower design to drive the camshaft, from 1946 to 1952;

2485-402: The 1925–1949 Velocette K Series and the 1927–1939 Norton CS1 . The 1946–1948 Crosley CC Four was arguably the first American mass-produced car to use an SOHC engine. This small mass-production engine powered the winner of the 1950 12 Hours of Sebring . Use of a DOHC configuration gradually increased after World War II, beginning with sports cars. Iconic DOHC engines of this period include

2556-544: The 1948–1959 Lagonda straight-six engine , the 1949–1992 Jaguar XK straight-six engine and the 1954–1994 Alfa Romeo Twin Cam inline-four engine. The 1966-2000 Fiat Twin Cam inline-four engine was one of the first DOHC engines to use a toothed timing belt instead of a timing chain. In the 1980s, the need for increased performance while reducing fuel consumption and exhaust emissions saw increasing use of DOHC engines in mainstream vehicles, beginning with Japanese manufacturers. By

2627-459: The East. The handle near the outer edge of the rotary part being the crank and human arm powering the rotation would be the connecting rod. However according to F. Lisheng and T. Qingjun, the hand-crank of the rotary quern was different from a crank, which was the combination of a hand-crank and a push-and-pull connecting rod by a hinge. The Antikythera mechanism, dated to around 200 BC, used

2698-531: The Hussite Wars: first, the connecting-rod, applied to cranks, reappeared; second, double-compound cranks also began to be equipped with connecting-rods; and third, the flywheel was employed for these cranks to get them over the 'dead-spot'. The concept was much improved by the Italian engineer and writer Roberto Valturio in 1463, who devised a boat with five sets, where the parallel cranks are all joined to

2769-576: The United States. The first DOHC engine was a Peugeot inline-four racing engine which powered the car that won the 1912 French Grand Prix . Another Peugeot with a DOHC engine won the 1913 French Grand Prix , followed by the Mercedes-Benz 18/100 GP with an SOHC engine winning the 1914 French Grand Prix . The Isotta Fraschini Tipo KM — built in Italy from 1910–1914— was one of the first production cars to use an SOHC engine. During World War I, both

2840-406: The camshaft is usually transferred to the valves either directly (using a tappet) or indirectly via a rocker arm . A dual overhead cam , double overhead cam , or twin-cam engine has two camshafts over each bank of the cylinder head, one for the intake valves and another for the exhaust valves. Therefore there are two camshafts for a straight engine and a total of four camshafts for a V engine or

2911-405: The camshaft. Timing belts are inexpensive, produce minimal noise and have no need for lubrication. A disadvantage of timing belts is the need for regular replacement of the belt; recommended belt life typically varies between approximately 50,000–100,000 km (31,000–62,000 mi). If the timing belt is not replaced in time and fails and the engine is an interference engine , major engine damage

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2982-435: The connecting rods. Most modern crankshafts are located in the engine block . They are made from steel or cast iron , using either a forging , casting or machining process. The crankshaft is located within the engine block and held in place via main bearings which allow the crankshaft to rotate within the block. The up-down motion of each piston is transferred to the crankshaft via connecting rods . A flywheel

3053-483: The crank, combined with a connecting rod in a machine, appears in the Ancient Greek Hierapolis sawmill in Roman Asia from the 3rd century AD and two stone sawmills at Gerasa , Roman Syria , and Ephesus , Greek Ionia under Rome, (both 6th century AD). On the pediment of the Hierapolis mill, a waterwheel fed by a mill race is shown powering via a gear train two frame saws which cut rectangular blocks by

3124-460: The crankshaft and the camshaft is commonly used in diesel overhead camshaft engines used in heavy trucks. Gear trains are not commonly used in engines for light trucks or automobiles. Several OHC engines up until the 1950s used a shaft with bevel gears to drive the camshaft. Examples include the 1908–1911 Maudslay 25/30 , the Bentley 3 Litre , the 1917-? Liberty L-12 , the 1929-1932 MG Midget ,

3195-451: The crankshaft determines the stroke length of the engine. Most modern car engines are classified as "over square" or short-stroke, wherein the stroke is less than the diameter of the cylinder bore . A common way to increase the low-RPM torque of an engine is to increase the stroke, sometimes known as "stroking" the engine. Historically, the trade-off for a long-stroke engine was a lower rev limit and increased vibration at high RPM, due to

3266-425: The crankshaft with no offset. When a straight engine is mounted at an angle, it is sometimes called a "slant engine". Types of straight engines include: V engines (also known as "Vee engines") have the cylinders aligned in two separate planes or 'banks', so that they appear to be in a "V" when viewed along the axis of the crankshaft. Types of V engines include: VR5 and VR6 engines are very compact and light, having

3337-457: The crankshaft, due to the high forces of combustion present. Flexing of the crankshaft was a factor in V8 engines replacing straight-eight engines in the 1950s; the long crankshafts of the latter suffered from an unacceptable amount of flex when engine designers began using higher compression ratios and higher engine speeds (RPM). The distance between the axis of the crankpins and the axis of

3408-402: The cylinder wall, which causes friction between the piston and cylinder wall. To prevent this, some early engines – such as the 1900–1904 Lanchester Engine Company flat-twin engines – connected each piston to two crankshafts that are rotating in opposite directions. This arrangement cancels out the lateral forces and reduces the requirement for counterweights. This design is rarely used, however

3479-409: The following categories: Crankshaft A crankshaft is a mechanical component used in a piston engine to convert the reciprocating motion into rotational motion . The crankshaft is a rotating shaft containing one or more crankpins , that are driven by the pistons via the connecting rods . The crankpins are also called rod bearing journals , and they rotate within the "big end" of

3550-488: The gas flow through the engine, increasing power output and fuel efficiency . The oldest configuration of overhead camshaft engine is the single overhead camshaft (SOHC) design. A SOHC engine has one camshaft per bank of cylinders, therefore a straight engine has a total of one camshaft and a V engine or flat engine has a total of two camshafts (one for each cylinder bank). Most SOHC engines have two valves per cylinder, one intake valve and one exhaust valve. Motion of

3621-406: The height of the cylinder block to vary during operating conditions. This expansion caused difficulties for pushrod engines, so an overhead camshaft engine using a shaft drive with sliding spline was the easiest way to allow for this expansion. These bevel shafts were usually in an external tube outside the block, and were known as "tower shafts". An early American overhead camshaft production engine

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3692-568: The high material cost, and the additional heat treatment required. However, since no expensive tooling is needed, this production method allows small production runs without high up-front costs. The earliest hand-operated cranks appeared in China during the Han dynasty (202 BC – 220 AD). They were used for silk-reeling, hemp-spinning, for the agricultural winnowing fan, in the water-powered flour-sifter, for hydraulic-powered metallurgic bellows , and in

3763-587: The increased piston velocity. When designing an engine, the crankshaft configuration is closely related to the engine's firing order . Most production V8 engines (such as the Ford Modular engine and the General Motors LS engine ) use a cross-plane crank whereby the crank throws are spaced 90 degrees apart. However, some high-performance V8 engines (such as the Ferrari 488 ) instead use

3834-545: The inter-conversion or rotary and reciprocating motion for other applications such as flour-sifting, treadle spinning wheels, water-powered furnace bellows, and silk-reeling machines. Ancient Egyptians had manual drills resembling a crank at the time of the Old Kingdom (2686–2181 BCE) and even a hieroglyph for the tool. However the Ancient Egyptian drill did not operate as a true crank. Later evidence for

3905-568: The later Mercedes D.IIIa design's partly-exposed SOHC valvetrain design; and the Max Friz -designed; German BMW IIIa straight-six engine. The DOHC Napier Lion W12 engine was built in Great Britain beginning in 1918. Most of these engines used a shaft to transfer drive from the crankshaft up to the camshaft at the top of the engine. Large aircraft engines— particularly air-cooled engines— experienced considerable thermal expansion, causing

3976-516: The mid-2000s, most automotive engines used a DOHC layout. Cylinder bank The engine configuration describes the fundamental operating principles by which internal combustion engines are categorized. Piston engines are often categorized by their cylinder layout, valves and camshafts. Wankel engines are often categorized by the number of rotors present. Gas turbine engines are often categorized into turbojets, turbofans, turboprops and turboshafts. Piston engines are usually designed with

4047-401: The number of main bearings required. The downside of flying arms is that the rigidity of the crankshaft is reduced, which can cause problems at high RPM or high power outputs. In most engines, each connecting rod is attached a single crankshaft, which results in the angle of the connecting rod varying as the piston moves through its stroke. This variation in angle pushes the pistons against

4118-555: The piston, conrods and crankshaft, in order to improve the engine balance . These counterweights are typically cast as part of the crankshaft but, occasionally, are bolt-on pieces. In some engines, the crankshaft contains direct links between adjacent crankpins , without the usual intermediate main bearing. These links are called flying arms . This arrangement is sometimes used in V6 and V8 engines , in order to maintain an even firing interval while using different V angles, and to reduce

4189-454: The rights to the Crosley engine format were bought by a few different companies, including General Tire in 1952, followed by Fageol in 1955, Crofton in 1959, Homelite in 1961, and Fisher Pierce in 1966, after Crosley closed the automotive factory doors, and they continued to produce the same engine for several more years. A camshaft drive using three sets of cranks and rods in parallel

4260-685: The same size, and will often have better engine balance characteristics, resulting in reduced engine vibration and potentially higher maximum engine speeds. Most engines with four or less cylinders use a straight engine layout, and most engines with eight cylinders or more use a V engine layout. However, there are various exceptions to this, such as the straight-eight engines used by various luxury cars from 1919-1954, V4 engines used by some marine outboard motors, V-twin and flat-twin engines used by motorcycles and flat-four engines used by various cars. Straight engines (also known as "inline engines") have all cylinders aligned in one row along

4331-449: The surface hardening of the bearing surfaces. The low alloy content also makes the material cheaper than high-alloy steels. Carbon steels also require additional heat treatment to reach the desired properties. Another construction method is to cast the crankshaft from ductile iron. Cast iron crankshafts are today mostly found in cheaper production engines where the loads are lower. Crankshafts can also be machined from billet , often

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4402-558: The technological treatises of the period: Agostino Ramelli 's The Diverse and Artifactitious Machines of 1588 depicts eighteen examples, a number that rises in the Theatrum Machinarum Novum by Georg Andreas Böckler to 45 different machines. Cranks were formerly common on some machines in the early 20th century; for example almost all phonographs before the 1930s were powered by clockwork motors wound with cranks. Reciprocating piston engines use cranks to convert

4473-447: The timing between each camshaft and the crankshaft. This affords better fuel economy by allowing a broader torque curve. Although each major manufacturer has their own trade name for their specific system of variable cam phasing systems, overall they are all classified as variable valve timing . The rotation of a camshaft is driven by a crankshaft . Many 21st century engines use a toothed timing belt made from rubber and kevlar to drive

4544-465: The valves directly via a bucket tappet . A DOHC design permits a wider angle between intake and exhaust valves than in SOHC engines, which improves the air-fuel mixture's flow through the engine. A further benefit is that the spark plug can be placed at the optimum location, which in turn improves combustion efficiency . Another newer benefit of DOHC engine design is the ability to independently change/phase

4615-427: The valves, whereas an OHC engine has the valves directly actuated by the camshaft. Compared with OHV engines with the same number of valves, there are fewer reciprocating components and less valvetrain inertia in an OHC engine. This reduced inertia in OHC engines results in less valve float at higher engine speeds (RPM). A downside is that the system used to drive the camshaft (usually a timing chain in modern engines)

4686-561: The way of some kind of connecting rods and, through mechanical necessity, cranks. The accompanying inscription is in Greek . The crank and connecting rod mechanisms of the other two archaeologically attested sawmills worked without a gear train. The crank appears in the mid-9th century in several of the hydraulic devices described by the Banū Mūsā brothers in their Book of Ingenious Devices . These devices, however, made only partial rotations and could not transmit much power, although only

4757-534: The well windlass . Pottery models with crank operated winnowing fans were unearthed dating back to the Western Han dynasty (202 BC - 9 AD). The rotary winnowing fan greatly increased the efficiency of separating grain from husks and stalks. The Chinese used the crank-and-connecting rod in ancient blasting apparatus, textile machinery and agricultural machinery no later than the Western Han dynasty (202 BC – 9 AD). Eventually crank-and-connecting rods were used in

4828-523: Was another early American luxury car to use a DOHC engine. Also in the United States, the DOHC Offenhauser racing engine was introduced in 1933. This inline-four engine dominated North American open-wheel racing from 1934 until the 1970s. Other early SOHC automotive engines were the 1920–1923 Wolseley Ten , the 1928-1931 MG 18/80 , the 1926–1935 Singer Junior and the 1928–1929 Alfa Romeo 6C Sport . Early overhead camshaft motorcycles included

4899-465: Was the 1962 Glas 1004 compact coupe. Another camshaft drive method commonly used on modern engines is a timing chain , constructed from one or two rows of metal roller chains . By the early 1960s most production automobile overhead camshaft designs used chains to drive the camshaft(s). Timing chains do not usually require replacement at regular intervals, however the disadvantage is that they are noisier than timing belts. A gear train system between

4970-532: Was the SOHC straight-eight engine used in the 1921–1926 Duesenberg Model A luxury car. In 1926, the Sunbeam 3 litre Super Sports became the first production car to use a DOHC engine. In the United States, Duesenberg added DOHC engines (alongside their existing SOHC engines) with the 1928 release of the Duesenberg Model J , which was powered by a DOHC straight-eight engine. The 1931–1935 Stutz DV32

5041-508: Was used in the 1920–1923 Leyland Eight luxury car built in the United Kingdom. A similar system was used in the 1926-1930 Bentley Speed Six and the 1930-1932 Bentley 8 Litre . A two-rod system with counterweights at both ends was used by many models of the 1958-1973 NSU Prinz . Among the first overhead camshaft engines were the 1902 Maudslay SOHC engine built in the United Kingdom and the 1903 Marr Auto Car SOHC engine built in

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