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Coilover Suspension
A coilover is an automobile suspension device. The name coilover is an abbreviation of "coil-over shock absorber". Description Coilovers are found on many vehicles, from RC cars to normal passenger cars, race cars and 4x4 vehicles. They are sometimes used as a factory suspension option on new cars. Coilovers are used in double wishbone suspension systems, and are often a component of MacPherson struts. Two of the main types of coilovers are full coilovers and slip-on coilovers. Full coilovers are matched up with a shock absorber from the factory, while with slip-on coilovers, the dampers and springs are bought separately and then assembled. There are a large number of companies who make aftermarket coilovers for vehicles, many of which allow the customer to adjust various settings such as ride height and damping. Camber and caster angles can also be adjusted if the car's suspension allows, and if the coilovers are supplied with adjustable top mounts. This high degree ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Body Roll
Body roll is the axial rotation of a vehicle’s body towards the outside of a turn. Body roll occurs because the compliance in vehicle suspension allows the vehicle body, which sits upon the suspension, to lean in the direction of the perceived centrifugal force acting upon the vehicle. Cause Vehicle suspension allows a vehicle’s wheels to move independently of its body. This smooths the ride for occupants and cargo while allowing the wheels to stay in contact with the ground over bumps. In a corner, the range of motion in the suspension allows the vehicle body to lean over toward the outside of the turn as the body tries to continue in a line tangential to the corner. Softer suspension with more travel will allow more body roll than harder suspension with less travel. Adverse effects Body roll allows a vehicle’s centre of mass to move towards the outside of the turn, increasing the load transfer to the outside wheels. This can cause understeer or oversteer to occur more ea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shock Absorbers
A shock absorber or damper is a mechanical or hydraulic device designed to absorb and damp shock impulses. It does this by converting the kinetic energy of the shock into another form of energy (typically heat) which is then dissipated. Most shock absorbers are a form of dashpot (a damper which resists motion via viscous friction). Description Pneumatic and hydraulic shock absorbers are used in conjunction with cushions and springs. An automobile shock absorber contains spring-loaded check valves and orifices to control the flow of oil through an internal piston (see below). One design consideration, when designing or choosing a shock absorber, is where that energy will go. In most shock absorbers, energy is converted to heat inside the viscous fluid. In hydraulic cylinders, the hydraulic fluid heats up, while in air cylinders, the hot air is usually exhausted to the atmosphere. In other types of shock absorbers, such as electromagnetic types, the dissipated energy can be s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anti-roll Bar
An anti-roll bar (roll bar, anti-sway bar, sway bar, stabilizer bar) is a part of many automobile suspensions that helps reduce the body roll of a vehicle during fast cornering or over road irregularities. It connects opposite (left/right) wheels together through short lever arms linked by a torsion spring. A sway bar increases the suspension's roll stiffness—its resistance to roll in turns—independent of its spring rate in the vertical direction. The first stabilizer bar patent was awarded to Canadian inventor Stephen Coleman of Fredericton, New Brunswick on April 22, 1919. Anti-roll bars were unusual on pre-WW2 cars due to the generally much stiffer suspension and acceptance of body roll. From the 1950s on, however, production cars were more commonly fitted with anti-roll bars, especially those vehicles with softer coil spring suspension. Purpose and operation An anti-sway or anti-roll bar is intended to force each side of the vehicle to lower, or rise, to similar heig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Strut Bar
A strut bar, strut brace, or strut tower brace (STB) is an automotive suspension accessory on a monocoque or unibody chassis to provide extra stiffness between the strut towers. With a MacPherson strut suspension system where the spring and shock absorber are combined in the one suspension unit which also replaces the upper control arm, the entire vertical suspension load is transmitted to the top of the vehicle's strut tower, unlike a double wishbone suspension where the spring and shock absorber may share the load separately. In general terms, a strut tower in a monocoque chassis is a reinforced portion of the inner wheel well and is not necessarily directly connected to the main chassis rails. For this reason there is inherent flex within the strut towers relative to the chassis rails. A strut bar is designed to reduce this strut tower flex by tying the two strut towers together. This transmits the load off each strut tower during cornering which ties the two towers together a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chapman Strut
The Chapman strut is a design of independent rear suspension used for light cars, particularly sports and racing cars. It takes its name from, and is best known for its use by, Colin Chapman of Lotus. The characteristic feature of the Chapman strut is a long upright strut combining a coil spring and shock absorber, with a universal-jointed drive shaft itself forming the lower link of the suspension. Origins Stout Scarab The design's origin lies with William Stout's 1932 Stout Scarab. This rear-engined car used swing axle independent rear suspension, with long near-vertical coilover struts from high mounting points on the space frame chassis. Stout had also been an aircraft designer and considered that the long-travel oleo struts made, '' 'the airplane landing gear '' s' the easiest type of running gear for comfort yet devised.' '' The lower ends of the struts were attached to the swing axle casings by swivel bushes. Forward radius rods handled the longitudinal forces. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Automotive Suspension Design
Automotive suspension design is an aspect of automotive engineering, concerned with designing the suspension for cars and trucks. Suspension design for other vehicles is similar, though the process may not be as well established. The process entails *Selecting appropriate vehicle level targets *Selecting a system architecture *Choosing the location of the 'hard points', or theoretical centres of each ball joint or bushing *Selecting the rates of the bushings *Analysing the loads in the suspension *Designing the spring rates *Designing shock absorber characteristics *Designing the structure of each component so that it is strong, stiff, light, and cheap *Analysing the vehicle dynamics of the resulting design Since the 1990s the use of multibody simulation and finite element software has made this series of tasks more straightforward. Vehicle level targets A partial list would include: *Maximum steady state lateral acceleration (in understeer mode) *Roll stiffness (degrees pe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Compression (physics)
In mechanics, compression is the application of balanced inward ("pushing") forces to different points on a material or structure, that is, forces with no net sum or torque directed so as to reduce its size in one or more directions.Ferdinand Pierre Beer, Elwood Russell Johnston, John T. DeWolf (1992), "Mechanics of Materials". (Book) McGraw-Hill Professional, It is contrasted with tension or traction, the application of balanced outward ("pulling") forces; and with shearing forces, directed so as to displace layers of the material parallel to each other. The compressive strength of materials and structures is an important engineering consideration. In uniaxial compression, the forces are directed along one direction only, so that they act towards decreasing the object's length along that direction. The compressive forces may also be applied in multiple directions; for example inwards along the edges of a plate or all over the side surface of a cylinder, so as to reduce it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bushing (isolator)
A bushing or rubber bushing is a type of vibration isolator. It provides an interface between two parts, damping the energy transmitted through the bushing. A common application is in vehicle suspension systems, where a bushing made of rubber (or, more often, synthetic rubber or polyurethane) separates the faces of two metal objects while allowing a certain amount of movement. This movement allows the suspension parts to move freely, for example, when traveling over a large bump, while minimizing transmission of noise and small vibrations through to the chassis of the vehicle. A rubber bushing may also be described as a flexible mounting or antivibration mounting. These bushings often take the form of an annular cylinder of flexible material inside a metallic casing or outer tube. They might also feature an internal ''crush tube'' which protects the bushing from being crushed by the fixings which hold it onto a threaded spigot. Many different types of bushing designs exist. An ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spring Rate
A spring is an elastic object that stores mechanical energy. In everyday use the term often refers to coil springs, but there are many different spring designs. Modern springs are typically manufactured from spring steel, although some non-metallic objects like the bow are also springs. When a conventional spring, without stiffness variability features, is compressed or stretched from its resting position, it exerts an opposing force approximately proportional to its change in length (this approximation breaks down for larger deflections). The ''rate'' or ''spring constant'' of a spring is the change in the force it exerts, divided by the change in deflection of the spring. That is, it is the gradient of the force versus deflection curve. An extension or compression spring's rate is expressed in units of force divided by distance, for example or N/m or lbf/in. A torsion spring is a spring that works by twisting; when it is twisted about its axis by an angle, it produces ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nut (hardware)
A nut is a type of fastener with a screw thread, threaded hole. Nuts are almost always used in conjunction with a mating bolt (fastener), bolt to fasten multiple parts together. The two partners are kept together by a combination of their threads' friction (with slight deformation (engineering)#Elastic deformation, elastic deformation), a slight Tension (physics), stretching of the bolt, and compression (physics), compression of the parts to be held together. In applications where vibration or rotation may work a nut loose, various locking mechanisms may be employed: lock washers, jam nuts, eccentric double nuts, specialist adhesive thread-locking fluid such as Loctite, safety pins (split pins) or lockwire in conjunction with castellated nuts, nylon inserts (nyloc nut), or slightly oval-shaped threads. Square nuts, as well as bolt heads, were the first shape made and used to be the most common largely because they were much easier to manufacture, especially by hand. While rare to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Preload (engineering)
Preload is an engineering term with several meanings. In the general sense, it refers to the internal application of stress to certain mechanical systems. Fastener preload ' The most common usage is to describe the load applied to a fastener as a result of its being installed, i.e., before any external loads are applied (e.g., tightening the nut on a bolt). Preload in such cases is important for several reasons. First, a tightened bolt experiences only a small fraction of any external load that will be applied later, so that a fully tightened bolt can (depending on the exact application) sustain a much greater load than a loosely tightened bolt. Second, a nut that is correctly tightened will resist becoming loose under the influence of vibration, temperature cycling, etc. Bearing preload Internal stress to a bearing through application of negative clearance is known as bearing preloading. Advantages of preloading include the following: maintain axial and radial position for a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
