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by . Unsourced material may be challenged and removed. (October 2012) ()
4-cylinder straight engine scheme
The straight or inline engine is an
aligned in one row and having no offset. Usually found in four, six and eight
configurations, they have been used in ,
and , although the term in-line has a broader meaning when applied to , see .[]
A straight engine is considerably easier to build than an otherwise equivalent
or , because both the
can be milled from a single metal , and it requires fewer
and . In-line engines are also smaller in overall physical dimensions than designs such as the , and can be mounted in any direction. Straight configurations are simpler than their V-shaped counterparts. Although six-cylinder engines are inherently balanced,[] the four-cylinder models are inherently off balance and rough, unlike 90-degree V fours[] and horizontally opposed 'boxer' four cylinders.
is the most common four-cylinder configuration, whereas the
has largely given way to the , which although not as naturally smooth-running is smaller in both length and height and easier to fit into the engine bay of smaller modern cars. Some manufacturers, including , , , ,
and , have also used
configurations. The
family includes straight-four, straight-five, and straight-six engines. Some small cars have
Once, the straight-eight was the prestig it could be made more cheaply than a V-engine by luxury car makers, who would focus on other specifics than the geometric ones, and even built engines more powerful than any . In the 1930s,
made from , with
per cylinder and hemispherical heads to produce the most powerful engine on the market. It was thus a selling point for
to introduce the
in 1933. However, following , the straight-eight was supplanted by the lighter and more compact V8 engine, which allowed shorter engine bays to be used in the design.
When a straight engine is mounted at an angle from the vertical it is called a slant engine. 's
was used in many models in the 1960s and 1970s.
also often mounts its straight-four and straight-five engines at a slant, as on the
initially used the
tilted at 45 degrees for the , but later versions of the engine were less tilted.
Two main factors have led to the recent decline of the straight-six in automotive applications. First, Lanchester , an old idea reintroduced by Mitsubishi in the 1980s to overcome the natural imbalance of the inline-four engine and rapidly adopted by many other manufacturers, have made both inline-four and
smoother- the greater smoothness of the straight-six layout is no longer as great an advantage. Second, fuel consumption became more important, as cars became smaller and more space-efficient. The engine bay of a modern small or medium car, typically designed for an inline-four, often does not have room for a straight-six, but can fit a V6 with only minor modifications.
Some manufacturers (originally , and more recently
with the ) have attempted to combine advantages of the straight and V configurations by producing a narrow-angle V; this is more compact than either configuration, but is less smooth (without balancing) than either.
Straight-6 engines are used in some models from , , , , , ,
with straight engines have their engines mounted with the row of cylinders horizontal. This differs from a
because it is essentially an inline engine laid on its side. Underfloor engines for buses and
(DMUs) commonly use this design. Such engines may be based on a conventional upright engine with alterations to make it suitable for horizontal mounting.
engine, an
, mounted in a
In aviation, the term "inline engine" is used more broadly, for any non- .
Some straight engines, in the strict sense, have been produced for aircraft. Renault produced a straight-four inverted air-cooled motor, which was used on the . A similar design was the
series of engines, used on the
and other aircraft. Advantages include improved visibility for the pilot in single-engined craft, and lower center of gravity.
This section needs expansion. You can help by . (December 2009)
Straight-4 engine installed in line with the frame of an
motorcycle
In motorcycling, the term "in-line" is sometimes used narrowly, for a straight engine mounted in line with the frame. A two-cylinder straight engine mounted across the frame is sometimes called a parallel twin. Other times, motorcycling experts treat the terms parallel, straight, and inline as equivalent, and use them interchangeably.
Today's Technician: Automotive Engine Performance. Douglas Vidler. Cengage Learning, 1 Jul 2003
Johnson, E. R. (). "Glossary". United States Naval Aviation, : Aircraft, Airships and Ships Between the Wars (illustrated ed.). McFarland. p. 326.  . INLINE ENGINE–A type of reciprocating piston engine in which an even (4-6-8-12) number of cylinders are arranged either in a straight line or in a V-type configuration directly above (or below) the crankcase. Most early inline aircraft engines were water-cooled via a radiator system, though air-cooled types began to appear during the 1930s.
Wilson, Hugo (1995). "Glossary". The Encyclopedia of the Motorcycle. London: Dorling Kindersley. pp. 309–310.  . in-line Engine layout in which the cylinders are arranged in a row, and in-line with the wheels of the machine.
Hunt, P McKay, M Wilson, H Robinson, James (2012), Duckworth, Mick, ed., , , , pp. 126, 210,  
Tuttle, Mark, Jr. (December 2005), "BMW F800S", Rider (. Web. 29 June 2012.), p. 15
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使用simple_form默认的bootstrap wrapper，默认输出的check_boxes是竖排，要想改成横排，需要在checkbox表单之外的label加上inline样式。使用 :item_wrapper_class =& :inline 即可。如下：
&%= f.association :roles, :as =& :check_boxes, :item_wrapper_class =& :inline %&
我在simple_form的github页面上居然没找到 :item_wrapper_class 这个东西，google之后发现simple_form的github的讨论页面 有人提到。记录在此免得以后忘了。
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GetMenu()->GetSubMenu(4)->CheckMenuItem(0,MF_BYPOSITION|MF_CHECKED); 这怎么错了在VS2005编译器中，这条语句引发了个错误中断。_AFXWIN_INLINE CMenu* CMenu::GetSubMenu(int nPos) const { ASSERT(::IsMenu(m_hMenu)); return CMenu::FromHandle(::GetSubMenu(m_hMenu, nPos)); }这是为什么呢？
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扫描下载二维码From Wikipedia, the free encyclopedia
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by . Unsourced material may be challenged and removed. (July 2009) ()
Ford inline-four engine with cylinder head removed
Renault-Nissan M9R 2.0 L Straight-4 DOHC Common rail diesel engine
The inline-four engine or straight-four engine is a type of
with all four
mounted in a straight line, or plane along the . The single bank of cylinders may be oriented in either a vertical or an inclined plane with all the
driving a common . Where it is inclined, it is sometimes called a slant-four. In a specification chart or when an abbreviation is used, an inline-four engine is listed either as I4 or L4 (for longitudinal, to avoid confusion between the digit 1 and the letter I).
The inline-four layout is in perfect
and confers a degree of mechanical simplicity which makes it popular for . However, despite its simplicity, it suffers from a secondary imbalance which causes minor vibrations in smaller engines. These vibrations become more powerful as engine size and power increase, so the more powerful engines used in larger cars generally are more complex designs with more than four cylinders.
Today almost all manufacturers of four-cylinder engines for automobiles produce the inline-four layout, with Subaru and Porsche 718
being notable exceptions, and so four-cylinder is usually synonymous with and a more widely used term than inline-four. The inline-four is the most common engine configuration in modern cars, while the
is the second most popular. In the late 2000s (decade), due to stringent government regulations mandating reduced vehicle emissions and increased fuel efficiency, the proportion of new vehicles sold in the U.S. with four-cylinder engines (largely of the inline-four type) rose from 30 percent to 47 percent between 2005 and 2008, particularly in mid-size vehicles where a decreasing number of buyers have chosen the V6 performance option.
configuration is the most common in
up to 3.0 L. In practice, the displacement of inline-four
in cars rarely exceeds this figure. For example, the largest engine of this form on the U.S. market in model year 2015 is the , which is available in the . However, there are some notable exceptions.
used a 3.0 L four in its
sports cars, the
came with a 2.9 L inline four, the
was available with a 3.2 L inline four from 1965 until 1980 and
produced several inline-four engines of 2,838 cc with basic cylinder dimensions of 3.5 in (89 mm) diameter and 4.5 in (110 mm) stroke (Rolls-Royce B40). Early vehicles also tended to have engines with larger displacements to develop horsepower and torque. The
was built with a 3.3 L inline-four engine.
Inline-four diesel engines, which are lower revving than gasoline engines, often exceed 3.0 L.
still employs a 3.2 L inline-four
(called the Shogun or Montero in certain markets), and several manufacturers of
vehicles, such as , , , , and
employ a 3.0 L inline-four diesel.
Larger inline-four engines are used in industrial applications, such as in small
and , are often found with displacements up to about 5 L.
for stationary, marine and
use (which run at low speeds) are made in much larger sizes.
Generally, European and Asian manufacturers of trucks with a
between 7.5 and 18 tonnes use inline four-cylinder diesel engines with displacements around 5 L. The
D0834 engine is a 4.6 L inline-4 with 220 hp (164 kW) and 627 lb?ft (850 N?m), which is available for the MAN TGL light-duty truck and VARIOmobil motorhomes. The
is a medium-duty truck which is available with a 5.2 L inline-four engine that delivers 210 hp (157 kW) and 470 lb?ft (640 N?m). The
is a medium-duty truck which is available with a 5.1 L inline-four engine that delivers 175 hp (130 kW) and 465 lb?ft (630 N?m). The earlier
even had a 5.3 L inline-four engine.
M135X is a tractor with a 6.1 L inline-four. This turbo-diesel engine has a bore of 118 mm (4.6 in) and a relatively long stroke of 140 mm (5.5 in).
One of the strongest Powerboat-4-cylinders is the
D4-300 turbodiesel. This is a 3.7 L-inline-4 with 300 hp (224 kW) and 516 lb?ft (700 N?m).
built a 127 kW (170 bhp) 3.7 L 4-cylinder gasoline engine (designated as the "470") for their
Inboard/outboard line. The block was formed from one half of a Ford 460 cubic inch V8 engine. This engine was produced in the 1970s and 1980s.[]
One of the largest inline-four engines is the MAN B&W 4K90 marine engine. This
has a giant displacement of 6,489 L. This results from a massive 0.9 meter bore and 2.5 meter stroke. The 4K90 engine develops 18,280 kW (24,854 PS; 24,514 hp) at 94 rpm and weighs 787 tons.
The largest on-road inline-4 cylinder turbo-diesel engine is the
, with a displacement of 8.5 L. It is widely used in various applications such as , trucks, and more. Power ratings varied from 250 hp to 350 hp. It was manufactured from 1994, until 2005. The Series 50 was also marketed as the Series 50G, for its
Displacement can also be very small, as found in
sold in , engines that started out at 550 cc and are currently at 660 cc, with ,
and superchargers resulting in engines that often claim the legal maximum of 64 PS (47 kW; 63 bhp). The
has a maximum power output of 114 hp (85 kW) and a maximum torque of 190 Nm (140 lbft) at a low rpm (1500 rpm).
Computer generated image showing the major internal moving parts of an inline-four engine with belt-driven double overhead camshafts and 4 valves per cylinder.
The inline-four engine is much smoother than one- or two-cylinder engines, and this has resulted in it becoming the engine of choice for most economy cars for many years. Its prominent advantage is the lack of rocking vibration, and the lack of need for heavy
makes it easier to be sporty (quick revving up and down). However, it tends to show
at high rpm because two pistons always move together, making the imbalance twice as strong as other configurations without them.
An even-firing inline-four engine is in primary balance because the pistons are moving in pairs, and one pair of pistons is always moving up at the same time as the other pair is moving down. However, piston acceleration and deceleration is greater in the top half of the crankshaft rotation than in the bottom half, because the connecting rods are not infinitely long, resulting in a . As a result, two pistons are always accelerating faster in one direction, while the other two are accelerating more slowly in the other direction, which leads to a secondary dynamic imbalance that causes an up-and-down vibration at twice crankshaft speed. This imbalance is common among all piston engines, but the effect is particularly strong on inline-four because of the two pistons always moving together.
The reason for the piston's higher speed during the 180° rotation from mid-stroke through top-dead-centre, and back to mid-stroke, is that the minor contribution to the piston's up/down movement from the connecting rod's change of angle here has the same direction as the major contribution to the piston's up/down movement from the up/down movement of the crank pin. By contrast, during the 180° rotation from mid-stroke through bottom-dead-centre and back to mid-stroke, the minor contribution to the piston's up/down movement from the connecting rod's change of angle has the opposite direction of the major contribution to the piston's up/down movement from the up/down movement of the crank pin.
The strength of this imbalance is determined by 1. Reciprocating mass, 2. Ratio of connecting rod length to stroke, and 3. Acceleration of piston movement. So small displacement engines with light pistons show little effect, and racing engines use long connecting rods. However, the effect grows exponentially with crankshaft rotational speed. See
article for unusual inline-four configurations.
Most inline-four engines below 2.0 L in displacement rely on the
to reduce the vibrations to acceptable levels. Above 2.0 L, most modern inline-four engines now use
to eliminate the . In a system invented by Dr.
in 1911, an inline-four engine uses two balance shafts, rotating in opposite directions at twice the crankshaft's speed, to offset the differences in piston speed. In the 1970s,
patented these balancer shafts to be located at different heights to further counter the rotational vibration created by the left and right swinging motion of connecting rods. , who used this technology on , and other car makers bought the license to this patent.
However, in the past, there were numerous examples of larger inline-fours without balance shafts, such as the
2,347 cc engine that was a derivative of the
engine, the  cc engine used in the
and , the 3.3 L
used in the , and the 2.5 L
used in a number of American cars and trucks. Soviet/Russian
SUVs, vans and light trucks used
big-bore inline-four engines (2.5 or later 2.9 L) with no balance shafts from the s. These engines were generally the result of a long incremental evolution process and their power was kept low compared to their capacity. However, the forces increase with the square of the engine speed — that is, doubling the speed makes the vibration four times more forceful — so some modern high-speed inline-fours, generally those with a displacement greater than 2.0 litres, have more need to use balance shafts to offset the vibration.
Animation of an Inline-four engine
Four-cylinder engines also have a smoothness problem in that the power strokes of the pistons do not overlap. With four cylinders and four strokes to complete in the four-stroke cycle, each piston completes its power stroke before the next piston starts a new power stroke, resulting in a pause between each power stroke and a pulsating delivery of power. In engines with more cylinders, the power strokes overlap, which gives them a smoother delivery of power and less
than a four can achieve. As a result, five-, six-, eight-, ten- and twelve-cylinder engines are generally used in more luxurious and expensive cars.
4-cylinder engines, often derided as "four bangers" do o an alloy block inline four is usually small, compact and lightweight, which serves to decrease overall vehicle mass, usually resulting in an increase in fuel efficiency in the urban cycle. The light weight of the inline four also allows for ease of removal and installation when maintenance or overhaul become necessary.
When compared to a V6 or V8, an inline four will generally have somewhat lower frictional losses at a comparable engine speed due to having fewer pistons, connecting rods and bearings, although the lower frictional loss is offset in practice by the inline four's need to operate at a higher RPM compared to a larger engine in order to produce equivalent power.
A notable inline 4 engine would be the BMW Megatron M12 1.5-litre Formula 1 straight-4 engine, which won the 1983 World Drivers Championship installed in the Brabham BT52 chassis driven by Nelson Piquet. In the second half of the 1983 Formula 1 season, the BMW was capable of over 800 BHP in qualifying, while in race trim usually had an output of between 640 BHP to 700 BHP depending on how much boost the drivers used.
GTV engine
automobile production inline-four engine powered the
.[] Displacing just 358 cc, the
was a conventional but tiny
engine. Honda produced, from 1963 to 1967, a 356 cc (21.7 cu in) inline-four engine for the
truck. Inline-four motorcycle engines are built down to 250 cc, e.g. in the .
Most inline-four engines, however, have been over 700 cc (43 cu in) displacement. A practical upper limit could be placed in the 2.5 L range for contemporary production cars. Larger engines (up to 6.1 L) have been seen in tractors (Kubota M135X) and medium duty
use (Isuzu Forward, Hino Ranger), especially using
(one of the strongest is the MAN D0834 engine with 220 hp (164 kW) and 627 lb?ft (850 N?m)). The use of balance shafts allowed
to use a 3.0 L (2,990 cc) inline-four engine on road cars first in the , but the largest modern non-diesel was the 3,186 cc (194.4 cu in)
produced from one half of the Division's 6,373 cc (388.9 cu in) V8 for the debut of its 1961 .
The largest mass-produced inline-four engine in a car has currently the Mitsubishi Pajero 3.2 DI-D, which has a 3,200 cc inline-four with 165 hp (123 kW) at 3,500 rpm (in Europe, 200 hp) and 381 N?m (281 lb?ft) at 2,000 rpm. The Engine has a bore of 98.5 mm (3.9 in) and a stroke of 105 mm (4.1 in).
Currently, one of the largest straight-4 engines in production is General Motors' Vortec 2900 installed in the GMC Canyon and Chevrolet Colorado small pickup trucks. It shares the same 95.5 mm (3.8 in) bore and 102 mm (4.0 in) stroke as the larger inline-five Vortec 3700. The latest version of the Vortec 2900, the LLV, displaces 2.9 L (;cc, 178 in?) and produces 185  (138 kW) at 5,600 rpm and 195 lb?ft (264 N?m) at 2,800 rpm. Engine redline is 6,300 rpm. Another example of a large inline-four engine is the Russian 2.89 L UMZ 421 series
In the early 20th century, bigger engines existed, both in road cars and sports cars. Due to the absence of displacement limit regulations, manufacturers took increasing liberties with engine size. In order to achieve power over 100 hp (75 kW), most engine builders simply increased displacement, which could sometimes achieve over 10.0 L. The biggest inline-four ever made was the 28.3 L engine used in the 1911 Fiat S76 racing car. These engines ran at very low rpm, often less than 1,500 rpm maximum, and had a specific output of about 10 hp/L. The US tractor industry both farm and industrial relied on large four-cylinder power units until the early 1960s, when six-cylinder designs came into favour. International Harvester built a large 5.7-litre (350 CID) four-cylinder for their WD-9 series tractors.
Other technologically or historically notable engines using this configuration include:
- one of the first mass-produced twin cam engines produced from 1954. Also first engine in production car with .
- the first engine to be used in a transverse drive train powering the front wheels of a mass-produced automobile ().
- 2.0 L all aluminum (block & head), DOHC, 16 valves, electronic fuel injection, stainless steel header.
A853 - intercooled turbo engine from the , set the land speed record for 4-cylinder production cars at the .
- One of the first mass-produced twincam engines, produced from 1959.
- one of the most widely produced engines in the world.
- twin-cam Oldsmobile engine offered in GM small, sporty cars.
- first use of Honda's
technology.
- its 250 PS (180 kW; 250 hp) from 2.0 L was the highest specific output of its time, particularly noteworthy in that it achieved this without .
- includes the 4G63, which has the highest specific output of a turbocharged production engine in the world with the Lancer Evolution FQ-400 available in the United Kingdom (202.9 hp/L)
- the first mass-produced
engine for
and an early
engine for .
- nicknamed the Go Devil engine. Powered the World War II
and post-war models. Notably undersquare, with 3.125 in (79.4 mm) bore and 4.375 in (111.1 mm) stroke.
In the late 2000s (decade), with auto manufacturers making efforts to increase fuel efficiency and reduce emissions, due to the high price of oil and the economic recession, the proportion of new vehicles with inline-four engines have increased considerably at the expense of V6 and V8 engines. This is particularly evident in mid-size vehicles where a decreasing number of buyers have chosen the V6 performance options.
Formula One Engine , 1500cc
1913 saw a
winning the . This car was powered by an inline-four engine designed by . This design was very influential for racing engines as it had, for the first time, dual overhead camshafts () and four
per cylinder, a layout that would become the standard until today for racing inline-four engines.
This Peugeot was sold to the American driver
who broke the engine in 1915. As Peugeot couldn't deliver a new engine during World War I, Burman asked
to build a new engine. With John Edward and , Miller created a Peugeot-inspired inline-four engine. This was the first version of the engine that would dominate the Indianapolis 500 until 1976 under the brand Miller and later . The Offenhausers won five straight victories at Indianapolis from 1971 to 1976, and it was not until 1981 that they were eliminated as competitors by engines such as the
Many cars produced for the pre-WWII
category used inline-four engine designs. 1.5 L
engines found their way into cars such as the
and various
(ERA) models. These were resurrected after the war, and formed the foundation of what was later to become , although the straight-eight supercharged Alfettas would dominate the early years of F1.
Another engine that played an important role in racing history is the inline-four
engine designed by . This engine was originally designed as a 2 L
engine for the Ferrari 500, but evolved to 2.5 L to compete in
in the Ferrari 625. For
racing, capacity was increased up to 3.4 L for the Ferrari 860 Monza.
Yet another very successful engine was the
inline-four originally designed by
as a 1.5 L Formula 2 engine. Enlarged to 2.0 L for Formula One in 1958, it evolved into the large 2,495 cc FPF that won the Formula One championship in 's chassis in 1959 and 1960.
In formula One, the 1980s were dominated by the 1,500 cc turbocharged cars. The
turbo was notable for the era for its high boost pressures and performance. The cast iron block 4-cylinder turbocharged Formula One motor, based on the standard BMW M10 engine introduced in 1961, powered the F1 cars of Brabham, Arrows and Benetton and won the world championship in 1983. In the years 1986 and 1987, the version M12/13/1 was tilted sideways by 72° for use in the extremely low . Unfortunately the design was not successful, probably due to cooling issues in the tight compartment. The 1986 engine was said to produce about 1,300 hp (969 kW) in qualifying.
Honda CB750 engine
Belgian arms manufacturer , which had been making
since 1901, began producing the first motorcycles with inline-fours in 1905. The
had its engine mounted upright with the crankshaft . Other manufacturers that used this layout included , , , , and
in the United States,
in Denmark, Windhoff in Germany, and
in the United Kingdom.
The first across-the-frame 4-cylinder motorcycle was the 1939 racer , it also had double-over-head camshafts, forced-inducting supercharger and was .Modern inline-four motorcycle engines first became popular with 's
introduced in 1969, and others followed in the 1970s. Since then, the inline-four has become one of the most common engine configurations in street bikes. Outside of the
category, the inline-four is the most common configuration because of its relatively high performance-to-cost ratio.[] All major Japanese motorcycle manufacturers offer motorcycles with inline-four engines, as do
and . BMW's earlier inline-four motorcycles were mounted horizontally along the frame, but all current four-cylinder BMW motorcycles have . The modern
company has offered inline-four-powered motorcycles, though they were discontinued in favour of .
has an inline-four engine that does not fire at even intervals of 180°. Instead, it uses a
crankshaft that prevents the pistons from simultaneously reaching top dead centre. This results in better , which is particularly beneficial in the higher rpm range, and "" theory says the irregular delivery of torque to the rear tire makes sliding in the corners at racing speeds easier to control.
When a connecting rod swings left on the top half of crank rotation, another swings right on the bottom half, with the connecting rod center of gravity (CG) heights located as much as the piston stroke apart. When the CG is located at different heights, the swing motion to the left cannot cancel the swing motion to the right, and a rocking vibration is introduced. By placing the balancer shafts at different heights, this vibration can be cancelled in addition to the cancellation of the secondary vibration.
. Porsche. 2016.
, pp. 13-16
Schembari, James (). . The New York Times.
Ulrich, Lawrence (). . The New York Times.
(PDF). Fueleconomy.gov.
(PDF). Archived from
(PDF) on .
. Archived from
. Archived from
. Archived from
(PDF). Archived from
(PDF) on .
. Hino Global.
(PDF). Archived from
(PDF) on .
. Archived from
(PDF). Archived from
(PDF) on .
Stevenson, Terry (). . Farmtrader.co.nz.
. Archived from
. Archived from
. Volvo Penta.
. Archived from
(PDF). Masson-marine.com.
, pp. 42-44
, p. 40-44.
. Mitsubishi-motors.de. . Archived from
. Grrc.goodwood.com.
. flickr.com.
, pp. 14–17
, pp. 182-185.
, pp. 78-81, 86-89.
, pp. 130-133.
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Siegal, Margie (May–June 2017). . .
Edwards, David (August 1997). Edwards, David, ed. . . Newport Beach, CA USA: Hachette Filipacchi Magazines. 36 (8): 42–43.  .
Hamish, Cooper (January–February 2018). . .
Ludvigsen, Karl (2001). Classic Racing Engines. Haynes Publishing.  .
Nunney, M J (2006). Light and Heavy Vehicle Technology (4th ed.). Butterworth-Heinemann.  .
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