|
Balance Shafts
Balance shafts are used in piston engines to reduce vibration by cancelling out unbalanced dynamic forces. The counter balance shafts have eccentric weights and rotate in the opposite direction to each other, which generates a net vertical force. The balance shaft was invented and patented by British engineer Frederick W. Lanchester in 1907. It is most commonly used in inline-four and V6 engines used in automobiles and motorcycles. Overview The operating principle of a balance shaft system is that two shafts carrying identical eccentric weights rotate in opposite directions at twice the engine speed. The phasing of the shafts is such that the centrifugal forces produced by the weights cancel the vertical second-order forces (at twice the engine RPM) produced by the engine. The horizontal forces produced by the balance shafts are equal and opposite, and so cancel each other. The balance shafts do not reduce the vibrations experienced by the crankshaft. Applications Two-c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Revolutions Per Minute
Revolutions per minute (abbreviated rpm, RPM, rev/min, r/min, or r⋅min−1) is a unit of rotational speed (or rotational frequency) for rotating machines. One revolution per minute is equivalent to hertz. Standards ISO 80000-3:2019 defines a physical quantity called ''rotation'' (or ''number of revolutions''), dimensionless, whose instantaneous rate of change is called ''rotational frequency'' (or ''rate of rotation''), with units of reciprocal seconds (s−1). A related but distinct quantity for describing rotation is ''angular frequency'' (or ''angular speed'', the magnitude of angular velocity), for which the SI unit is the radian per second (rad/s). Although they have the same dimensions (reciprocal time) and base unit (s−1), the hertz (Hz) and radians per second (rad/s) are special names used to express two different but proportional ISQ quantities: frequency and angular frequency, respectively. The conversions between a frequency and an angular frequency ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Balancing Machine
A balancing machine is a measuring tool used for balancing rotating machine parts such as rotors for electric motors, fans, turbines, disc brakes, disc drives, propellers and pumps. The machine usually consists of two rigid pedestals, with suspension and bearings on top supporting a mounting platform. The unit under test is bolted to the platform and is rotated either with a belt-, air-, or end-drive. As the part is rotated, the vibration in the suspension is detected with sensors and that information is used to determine the amount of unbalance in the part. Along with phase information, the machine can determine how much and where to add or remove weights to balance the part. Hard-bearing vs. soft-bearing There are two main types of balancing machines, hard-bearing and soft-bearing. The difference between them, however, is in the suspension and not the bearings. In a hard-bearing machine, balancing is done at a frequency lower than the resonance frequency of the suspe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volvo B8444S Engine
The B8444S is an automobile V8 engine manufactured by Yamaha Motor Company for Volvo Cars. It was built in Japan and based on Volvo designs. Usage Volvo began offering a V8 engine in its large Volvo P2 platform, P2 platform automobiles in 2005. It was initially offered only for the Volvo XC90 but later found its way in the second generation Volvo S80, and was mated to a six speed Aisin Seiki AWTF-80 SC, AWTF80-SC transmission of Japan also with a Swedish Haldex all-wheel drive (AWD) system. The 4.4 L V8 Volvo engine was built by Yamaha in Japan under Volvo design and specifications. Although the B8444S shares its Yamaha origination, its transverse layout, and its 60 degree bank angle, officials of all three companies involved insist that the Volvo V8 is not related to the Ford SHO V8 engine, SHO engine; the Die casting, die-cast open-deck aluminum Volvo block is clearly different from the Sand casting, sand-cast closed-deck aluminum SHO engine block although the two engines ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mercedes-Benz OM629
The Mercedes-Benz OM629 is a diesel-fuelled, 4-stroke, compression-ignition internal combustion 75° 32-valve V8 engine used in the 2000s. __TOC__ Design The block features an aluminium crankcase and cylinder heads. It uses aluminium sand casting in bedplate construction (divided at the height of the crankshaft) with wet cylinder liners made of cast iron. The main bearings are reinforced, cast in GGG ductile cast iron. Rather than the usual 90° " vee" angle between the cylinder banks, a 75° angle was chosen due to the space available to install the engine. The consequence of this specific angle is free inertial forces of the first order. To compensate for this, the OM628 and OM629 use a balancer shaft located in the vee of the engine. To ensure even firing intervals the crankshaft uses split crank pins. The engine uses 97.0 mm cylinder spacing. The engine uses dual overhead camshafts on each bank (‘quad-cam’) with four valves per cylinder, operated by hydraulic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flat-six Engine
A flat-six engine, also known as a horizontally opposed-six, is a six-cylinder piston engine with three cylinders on each side of a central crankshaft. The most common type of flat-six engine is the boxer-six engine, where each pair of opposed cylinders moves inwards and outwards at the same time. An alternative configuration for flat engines is a 180-degree V engine, where both cylinders move to the right then the left at the same time. The advantages of the flat-six layout are good engine balance (for reduced vibration), a low center of gravity, short length (compared with an inline-six engine) and being well suited to air-cooling. The disadvantages are a large width (which can limit the maximum steering angle when used in a front-engined car), a large intake manifold being required when a central carburetor is used, and duplication of the inlet and outlet connections for water-cooled engines. The first production flat-six engine was in the 1904 '' Wilson-Pilcher 18/24 HP'' c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Straight-six Engine
A straight-six engine (also referred to as an inline-six engine; abbreviated I6 or L6) is a piston engine with six cylinders arranged in a straight line along the crankshaft. A straight-six engine has perfect primary and secondary engine balance, resulting in fewer vibrations than other designs of six or fewer cylinders. Until the mid-20th century, the straight-six layout was the most common design for engines with six cylinders. However, V6 engines gradually became more common in the 1970s and by the 2000s, V6 engines had replaced straight-six engines in most light automotive applications. Characteristics In terms of packaging, straight-six engines are almost always narrower than a V6 engine or V8 engine, but longer than straight-four engines, V6s, and most V8s. Compared to V-configuration engines with similar power and displacement, the straight configuration has fewer injectors, a single head, and a single exhaust manifold, all contributing to better reliability and perfor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
General Motors Atlas Engine
Atlas is a name for a family of modern inline piston engines for trucks from General Motors, used in the GMT355 and GMT360 platforms. The series debuted in 2002 with the Oldsmobile Bravada, and is also used in the Buick Rainier, the Chevrolet TrailBlazer and Colorado, the GMC Envoy and Canyon, the Hummer H3, Isuzu Ascender and i-370, and the Saab 9-7X. The engines use GM's Vortec name, and straight-4, straight-5, and straight-6 engines are all part of the same family, sharing the same manufacturing equipment, rods, pistons, valves, and other parts. They feature coil-on-plug ignition systems, variable valve timing on the exhaust side, electronic throttle control, and a special oil pan with a pass-through for the half shafts in four-wheel drive vehicles. The inclusion of VVT on the exhaust camshaft side allows the Atlas series to meet emissions standards without the use of EGR, simplifying the engine design and increasing power for a broad power curve. The LL8 shares 75% of its c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Straight-five Engine
The straight-five engine (also referred to as an inline-five engine; abbreviated I5 or L5) is a piston engine with five cylinders mounted in a straight line along the crankshaft. Although less common than straight-four engines and straight-six engines, straight-five engine designs have been used by automobile manufacturers since the late 1930s. The most notable examples include the Mercedes Benz's diesel engines from 1974 to 2006 and Audi's petrol engines from 1979 to the present. Straight-five engines are smoother running than straight-four engines and shorter than straight-six engines. However, achieving consistent fueling across all cylinders was problematic prior to the adoption of fuel injection. Characteristics Straight-five engines are typically shorter than straight-six engines, making them easier to fit transversely in an engine bay. They are also smoother than straight-four engines, and are narrower than V engines and flat engines. Engine balance and vibration ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flat-four Engine
A flat-four engine, also known as a horizontally opposed-four engine or boxer engine, is a four-cylinder piston engine with two banks of cylinders lying on opposite sides of a common crankshaft. The most common type of flat-four engine is the boxer-four engine, each pair of opposed pistons moves inwards and outwards at the same time. A boxer-four engine has perfect primary and secondary balance, however, the two cylinder heads means the design is more expensive to produce than a straight-four engine. There is a minor, secondary unbalanced rotational torque pulse in the plane of the pistons, when a piston pair at one end of the engine is at TDC and the other pair at BDC. The TDC pair creates a torque greater than the BDC pair, so the net unbalanced torque pulse is the difference. The difference in TDC vs BDC inertial forces is explained in the Engine balance section. Boxer-four engines have been used in cars since 1897, especially by Volkswagen and Subaru. They have also occasional ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mitsubishi Astron Engine
The Mitsubishi Astron or 4G5/4D5 engine, is a series of Inline-four engine, straight-four internal combustion engines first built by Mitsubishi Motors in 1972. Engine displacement ranged from 1.8 to 2.6 litres, making it one of the largest four-cylinder engines of its time. Design It employed a hemispherical cylinder head, roller chain, chain-driven SOHC, single overhead camshaft (SOHC) and eight poppet valve, valves (two per cylinder). United States passenger car versions had a small secondary intake valve referred to as the "Jet Valve". This valve induced swirl in the intake charge, enabling the use of leaner fuel/air mixtures for lower emissions. It was designed as a cartridge containing the valve spring and seat which simply screwed into a threaded hole in the head, similar to a spark plug but inside the cam cover. The rocker arms for the intake valve were widened on the valve end to accommodate the cartridge, which was equipped with a very soft valve spring in order to avoid we ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bore (engine)
In a piston engine, the bore (or cylinder bore) is the diameter of each cylinder. Engine displacement is calculated based on bore, stroke length and the number of cylinders: displacement = The stroke ratio, determined by dividing the bore by the stroke, traditionally indicated whether an engine was designed for power at high engine speeds ( rpm) or torque at lower engine speeds. The term "bore" can also be applied to the bore of a locomotive cylinder or steam engine pistons. In steam locomotives The term bore also applies to the cylinder of a steam locomotive or steam engine. Bore pitch Bore pitch is the distance between the centerline of a cylinder bore to the centerline of the next cylinder bore adjacent to it in an internal combustion engine. It's also referred to as the "mean cylinder width", "bore spacing", "bore center distance" and "cylinder spacing". The bore pitch is always larger than the inside diameter of the cylinder (the bore and piston diameter) sinc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
