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VANOS
VANOS is a variable valve timing system used by BMW on various automotive petrol engines since 1992. The name is an abbreviation of the German words for ''variable camshaft timing'' (german: variable Nockenwellensteuerung). The initial version (retrospectively renamed "single VANOS") was solely used on the intake camshaft, while the later "double VANOS" systems are used on intake and exhaust camshafts. Since 2001, VANOS is often used in conjunction with the valvetronic variable valve lift system. Operation VANOS is a variator system that varies the timing of the valves by moving the position of the camshafts in relation to the drive gear. The relative timing between inlet and exhaust valves is changed. At lower engine speeds, the position of the camshaft is moved so the valves are opened later, as this improves idling quality and smooth power development. As the engine speed increases, the valves are opened earlier: this enhances torque, reduces fuel consumption and lowers em ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BMW M50
The BMW M50 is a straight-6 DOHC petrol engine which was produced from 1990 to 1996. It was released in the E34 520i and 525i, to replace the M20 engine. In September 1992, the M50 was upgraded to the M50TU ("technical update"), which was BMW's first engine to use variable valve timing. Called single VANOS by BMW, the system adjusted the phasing of the intake camshaft. The M50 began to be phased out following the introduction of the M52 engine in 1994. The E36 M3 is powered by the S50 engine series, which is a high output version of the M50. Design A significant advance over its M20 predecessor, the M50 features dual overhead camshaft (DOHC) with four valves per cylinder (the M20 has a single overhead camshaft with 2 valves per cylinder), coil-on-plug ignition, a knock sensor and a lightweight plastic intake manifold. Both engines use an iron block with an aluminum alloy head. The redline is 6,500 rpm for the M50B25 and 6,750 rpm for the M50B20 (7,000&nb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BMW M62
BMW M62 is a naturally aspirated V8 petrol engine which was produced from 1995 to 2005. A successor to the BMW M60, the M62 features an aluminium engine block and a single row timing chain. In 1998, a Technical Update included VANOS (variable valve timing) for the intake camshafts. The S62 engine is the BMW M high performance version of the M62, which was released in the E39 M5, BMW Z8, Ascari KZ1, and the Ascari A10. Design Like the BMW M60 engine it replaced, the M62 is a DOHC engine with four valves per cylinder, an aluminum block and aluminum heads. The M62 has fracture-split forged connecting rods, hypereutectic pistons with ferrous coated side skirts. Most of the M62 engines used Alusil for the block material, however some early M62 engines used Nikasil cylinder coating instead. Alusil technology integrates silicon throughout the aluminum cast so that liners or treated bores within this block family are not needed. The M62 uses a Bosch Motronic 5.2 engine contr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Valvetronic
The Valvetronic system is a BMW variable valve lift system which, in combination with VANOS, allows infinite adjustment of the intake valve timing and duration. The system claims to improve fuel economy and emissions, and negates the need for a throttle body in regular use. First introduced by BMW on the 316ti compact in 2001, Valvetronic has since been added to many of BMW's engines. The first application of this technology in a turbocharged engine was the N55 engine. See also * VANOS: BMW's variable valve timing * Prince engine Prince is the codename for a family of straight-four 16-valve all-aluminium gasoline engines with variable valve lift and variable valve timing developed by PSA Peugeot Citroën and BMW. It is a compact engine family of 1.4–1.6 L in disp ... References Variable valve timing BMW {{Auto-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Valvetronic
The Valvetronic system is a BMW variable valve lift system which, in combination with VANOS, allows infinite adjustment of the intake valve timing and duration. The system claims to improve fuel economy and emissions, and negates the need for a throttle body in regular use. First introduced by BMW on the 316ti compact in 2001, Valvetronic has since been added to many of BMW's engines. The first application of this technology in a turbocharged engine was the N55 engine. See also * VANOS: BMW's variable valve timing * Prince engine Prince is the codename for a family of straight-four 16-valve all-aluminium gasoline engines with variable valve lift and variable valve timing developed by PSA Peugeot Citroën and BMW. It is a compact engine family of 1.4–1.6 L in disp ... References Variable valve timing BMW {{Auto-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Variable Valve Timing
In internal combustion engines, variable valve timing (VVT) is the process of altering the timing of a valve lift event, and is often used to improve performance, fuel economy or emissions. It is increasingly being used in combination with variable valve lift systems. There are many ways in which this can be achieved, ranging from mechanical devices to electro-hydraulic and camless systems. Increasingly strict emissions regulations are causing many automotive manufacturers to use VVT systems. Two-stroke engines use a power valve system to get similar results to VVT. Background theory The valves within an internal combustion engine are used to control the flow of the intake and exhaust gases into and out of the combustion chamber. The timing, duration and lift of these valve events has a significant impact on engine performance. Without variable valve timing or variable valve lift, the valve timing is the same for all engine speeds and conditions, therefore compromises are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Variator (variable Valve Timing)
Variable valve timing (VVT) is a system for varying the valve opening of an internal combustion engine. This allows the engine to deliver high power, but also to work tractably and efficiently at low power. There are many systems for VVT, which involve changing either the relative timing, duration or opening of the engine's inlet and exhaust valves. One of the first practical VVT systems used a variator to change the phasePhase refers to the relative timing between the inlet and exhaust camshafts, expressed as an angular measure. of the camshaft and valves. This simple system cannot change the duration of the valve opening, or their lift.'Lift' is the distance by which the valves open. Later VVT systems, such as the helical camshaft or the movable fulcrum systems, could change these factors too. Despite this limitation, the variator is a relatively simple device to add to an existing engine and so they remain in service today. As the benefit of the variator relies on changing the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Variable Valve Timing
In internal combustion engines, variable valve timing (VVT) is the process of altering the timing of a valve lift event, and is often used to improve performance, fuel economy or emissions. It is increasingly being used in combination with variable valve lift systems. There are many ways in which this can be achieved, ranging from mechanical devices to electro-hydraulic and camless systems. Increasingly strict emissions regulations are causing many automotive manufacturers to use VVT systems. Two-stroke engines use a power valve system to get similar results to VVT. Background theory The valves within an internal combustion engine are used to control the flow of the intake and exhaust gases into and out of the combustion chamber. The timing, duration and lift of these valve events has a significant impact on engine performance. Without variable valve timing or variable valve lift, the valve timing is the same for all engine speeds and conditions, therefore compromises are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Petrol Engine
A petrol engine (gasoline engine in American English) is an internal combustion engine designed to run on petrol (gasoline). Petrol engines can often be adapted to also run on fuels such as liquefied petroleum gas and ethanol blends (such as ''E10'' and ''E85''). Most petrol engines use spark ignition, unlike diesel engines which typically use compression ignition. Another key difference to diesel engines is that petrol engines typically have a lower compression ratio. Design Thermodynamic cycle Most petrol engines use either the four-stroke Otto cycle or the two-stroke cycle. Petrol engines have also been produced using the Miller cycle and Atkinson cycle. Layout Most petrol-powered piston engines are straight engines or V engines. However, flat engines, W engines and other layouts are sometimes used. Wankel engines are classified by the number of rotors used. Compression ratio Cooling Petrol engines are either air-cooled or water-cooled. Ignition Pe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Poppet Valve
A poppet valve (also called mushroom valve) is a valve typically used to control the timing and quantity of gas or vapor flow into an engine. It consists of a hole or open-ended chamber, usually round or oval in cross-section, and a plug, usually a disk shape on the end of a shaft known as a valve stem. The working end of this plug, the valve face, is typically ground at a 45° bevel to seal against a corresponding valve seat ground into the rim of the chamber being sealed. The shaft travels through a valve guide to maintain its alignment. A pressure differential on either side of the valve can assist or impair its performance. In exhaust applications higher pressure against the valve helps to seal it, and in intake applications lower pressure helps open it. The poppet valve was invented in 1833 by American E.A.G. Young of the Newcastle and Frenchtown Railroad. Young had patented his idea, but the Patent Office fire of 1836 destroyed all records of it. Etymology The word ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Camshaft
A camshaft is a shaft that contains a row of pointed cams, in order to convert rotational motion to reciprocating motion. Camshafts are used in piston engines (to operate the intake and exhaust valves), mechanically controlled ignition systems and early electric motor speed controllers. Camshafts in piston engines are usually made from steel or cast iron, and the shape of the cams greatly affects the engine's characteristics. History Trip hammers are one of the early uses of a form of cam to convert rotating motion, e.g. from a waterwheel, into the reciprocating motion of a hammer used in forging or to pound grain. Evidence for these exists back to the Han Dynasty in China, and they were widespread by the medieval period. The camshaft was described in 1206 by engineer Al-Jazari. He employed it as part of his automata, water-raising machines, and water clocks such as the castle clock. Once the rotative version of the steam engine was developed in the late 18th century, the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rotational Speed
Rotational frequency (also known as rotational speed or rate of rotation) of an object rotating around an axis is the frequency of rotation of the object. Its unit is revolution per minute (rpm), cycle per second (cps), etc. The symbol for rotational frequency is \nu (the Greek lowercase letter nu). Tangential speed ''v'', rotational frequency \nu, and radial distance ''r'', are related by the following equation: :v = 2\pi r\nu :v = r\omega An algebraic rearrangement of this equation allows us to solve for rotational frequency: :\nu = v/2\pi r :\omega = v/r Thus, the tangential speed will be directly proportional to ''r'' when all parts of a system simultaneously have the same ''ω'', as for a wheel, disk, or rigid wand. The direct proportionality of ''v'' to ''r'' is not valid for the planets, because the planets have different rotational frequencies. Rotational frequency can measure, for example, how fast a motor is running. ''Rotational speed'' is sometimes used ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
