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Hydrostatic Transmission
A continuously variable transmission (CVT) is an automatic transmission that can change seamlessly through a continuous range of gear ratios. This contrasts with other transmissions that provide a limited number of gear ratios in fixed steps. The flexibility of a CVT with suitable control may allow the engine to operate at a constant Revolutions per minute, RPM while the vehicle moves at varying speeds. CVTs are used in cars, tractors, Side-by-side (vehicle), side-by-sides, motor scooters, snowmobiles, bicycles, and Heavy equipment, earthmoving equipment. The most common type of CVT uses two pulleys connected by a Belt (mechanical), belt or Chain drive, chain; however, several other designs have also been used at times. Types Pulley-based The most common type of CVT uses a V-belt which runs between two variable-diameter pulleys. The pulleys consist of two cone-shaped halves that move together and apart. The V-belt runs between these two-halves, so the effective diamete ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lubrication
Lubrication is the process or technique of using a lubricant to reduce friction and wear and tear in a contact between two surfaces. The study of lubrication is a discipline in the field of tribology. Lubrication mechanisms such as fluid-lubricated systems are designed so that the applied load is partially or completely carried by hydrodynamic or hydrostatic pressure, which reduces solid body interactions (and consequently friction and wear). Depending on the degree of surface separation, different lubrication regimes can be distinguished. Adequate lubrication allows smooth, continuous operation of machine elements, reduces the rate of wear, and prevents excessive stresses or seizures at bearings. When lubrication breaks down, components can rub destructively against each other, causing heat, local welding, destructive damage and failure. Lubrication mechanisms Fluid-lubricated systems As the load increases on the contacting surfaces, distinct situations can be observed wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Swashplate Anim Metal
A swashplate, also known as slant disk, was invented by Anthony Michell in 1917. It is a mechanical engineering device used to translate the motion of a rotating shaft into reciprocating motion, or vice versa. The working principle is similar to crankshaft, Scotch yoke, or wobble/nutator/Z-crank drives, in engine designs. It was originally invented to replace a crankshaft, and is one of the most popular concepts used in crankless engines. Construction A swashplate consists of a disk attached to a shaft. If the disk were aligned perpendicular to the shaft, then rotating the shaft would merely turn the disk with no reciprocating (or ''swashplate'') effect. But instead the disk is mounted at an oblique angle, which causes its edge to appear to describe a path that oscillates along the shaft's length as observed from a non-rotating point of view away from the shaft. The greater the disk's angle to the shaft, the more pronounced is this apparent linear motion. The apparent linear mot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Non-circular Gear
A non-circular gear (NCG) is a special gear design with special characteristics and purpose. While a regular gear is optimized to transmit torque to another engaged member with minimum noise and wear and with maximum efficiency, a non-circular gear's main objective might be ratio variations, axle displacement oscillations and more. Common applications include textile machines, potentiometers, CVTs (continuously variable transmissions), window shade panel drives, mechanical presses and high torque hydraulic engines. A regular gear pair can be represented as two circles rolling together without slip. In the case of non-circular gears, those circles are replaced with anything different from a circle. For this reason NCGs in most cases are not round, but round NCGs looking like regular gears are also possible (small ratio variations result from meshing area modifications). Generally NCG should meet all the requirements of regular gearing, but in some cases, for example variable axle ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scotch Yoke
The Scotch Yoke (also known as slotted link mechanism) is a reciprocating motion mechanism, converting the linear motion of a slider into rotational motion, or vice versa. The piston or other reciprocating part is directly coupled to a sliding yoke with a slot that engages a pin on the rotating part. The location of the piston versus time is simple harmonic motion, i.e., a sine wave having constant amplitude and constant frequency, given a constant rotational speed. Applications This setup is most commonly used in control valve actuators in high-pressure oil and gas pipelines. Although not a common metalworking machine nowadays, crude shapers can use Scotch yokes. Almost all those use a Whitworth linkage, which gives a slow speed forward cutting stroke and a faster return. It has been used in various internal combustion engines, such as the Bourke engine, SyTech engine, and many hot air engines and steam engines. The term ''scotch yoke'' continues to be used when the slot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oscillation
Oscillation is the repetitive or periodic variation, typically in time, of some measure about a central value (often a point of equilibrium) or between two or more different states. Familiar examples of oscillation include a swinging pendulum and alternating current. Oscillations can be used in physics to approximate complex interactions, such as those between atoms. Oscillations occur not only in mechanical systems but also in dynamic systems in virtually every area of science: for example the beating of the human heart (for circulation), business cycles in economics, predator–prey population cycles in ecology, geothermal geysers in geology, vibration of strings in guitar and other string instruments, periodic firing of nerve cells in the brain, and the periodic swelling of Cepheid variable stars in astronomy. The term ''vibration'' is precisely used to describe a mechanical oscillation. Oscillation, especially rapid oscillation, may be an undesirable phenomenon in proc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rotation Around A Fixed Axis
Rotation around a fixed axis is a special case of rotational motion. The fixed-axis hypothesis excludes the possibility of an axis changing its orientation and cannot describe such phenomena as wobbling or precession. According to Euler's rotation theorem, simultaneous rotation along a number of stationary axes at the same time is impossible; if two rotations are forced at the same time, a new axis of rotation will appear. This article assumes that the rotation is also stable, such that no torque is required to keep it going. The kinematics and dynamics of rotation around a fixed axis of a rigid body are mathematically much simpler than those for free rotation of a rigid body; they are entirely analogous to those of linear motion along a single fixed direction, which is not true for ''free rotation of a rigid body''. The expressions for the kinetic energy of the object, and for the forces on the parts of the object, are also simpler for rotation around a fixed axis, than for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ratchet (device)
A ratchet (occasionally spelled rachet) is a mechanical device that allows continuous linear or rotary motion in only one direction while preventing motion in the opposite direction. Ratchets are widely used in machinery and tools. The word ''ratchet'' is also used informally to refer to a ratcheting socket wrench. __TOC__ Theory of operation A ratchet consists of a round gear or a linear rack with teeth, and a pivoting, spring-loaded finger called a '' pawl'' (or ''click'', in clocks and watches) that engages the teeth. The teeth are uniform but are usually asymmetrical, with each tooth having a moderate slope on one edge and a much steeper slope on the other edge. When the teeth are moving in the unrestricted (i.e. forward) direction, the pawl easily slides up and over the gently sloped edges of the teeth, with a spring forcing it (often with an audible 'click') into the depression between the teeth as it passes the tip of each tooth. When the teeth move in the opposite ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clutch
A clutch is a mechanical device that engages and disengages power transmission, especially from a drive shaft to a driven shaft. In the simplest application, clutches connect and disconnect two rotating shafts (drive shafts or line shafts). In these devices, one shaft is typically attached to an engine or other power unit (the driving member), while the other shaft (the driven member) provides output power for work. Typically the motions involved are rotary, but linear clutches also exist. In a motor vehicle, the clutch acts as a mechanical linkage between the engine and transmission, and briefly disconnects, or separates the engine from the transmission system. This disconnects the drive wheels whenever the clutch pedal is depressed, allowing the driver to smoothly change gears. In a torque-controlled drill, for instance, one shaft is driven by a motor, and the other drives a drill chuck. The clutch connects the two shafts so they may be locked together and spin at the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Perpendicular
In elementary geometry, two geometric objects are perpendicular if they intersect at a right angle (90 degrees or π/2 radians). The condition of perpendicularity may be represented graphically using the ''perpendicular symbol'', ⟂. It can be defined between two lines (or two line segments), between a line and a plane, and between two planes. Perpendicularity is one particular instance of the more general mathematical concept of '' orthogonality''; perpendicularity is the orthogonality of classical geometric objects. Thus, in advanced mathematics, the word "perpendicular" is sometimes used to describe much more complicated geometric orthogonality conditions, such as that between a surface and its '' normal vector''. Definitions A line is said to be perpendicular to another line if the two lines intersect at a right angle. Explicitly, a first line is perpendicular to a second line if (1) the two lines meet; and (2) at the point of intersection the straight angle on one side ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Torus
In geometry, a torus (plural tori, colloquially donut or doughnut) is a surface of revolution generated by revolving a circle in three-dimensional space about an axis that is coplanar with the circle. If the axis of revolution does not touch the circle, the surface has a ring shape and is called a torus of revolution. If the axis of revolution is tangent to the circle, the surface is a horn torus. If the axis of revolution passes twice through the circle, the surface is a spindle torus. If the axis of revolution passes through the center of the circle, the surface is a degenerate torus, a double-covered sphere. If the revolved curve is not a circle, the surface is called a ''toroid'', as in a square toroid. Real-world objects that approximate a torus of revolution include swim rings, inner tubes and ringette rings. Eyeglass lenses that combine spherical and cylindrical correction are toric lenses. A torus should not be confused with a '' solid torus'', which is formed by r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nissan Cedric
The is a large automobile produced by Nissan since 1960. It was developed to provide upscale transportation, competing with the Prince Skyline and Gloria which were later merged into the Nissan family. In later years, the Nissan Skyline was positioned as a sports sedan/coupe, whereas the Nissan Gloria was turned into a sporty version of the Cedric (with identical styling but using a different radiator grille and front & rear light clusters). In Japan, the Cedric/Gloria series was affectionately called CedGlo, and this long-running series finally came to an end in October 2004, replaced by the Nissan Fuga. The Cedric name is still in use, on the Y31 series fleet vehicle traditionally used as a taxi, where it competes with the Toyota Comfort, and is still in production. Throughout the many versions of the Cedric, it was always considered to be the prime competitor to the Toyota Crown. The hood ornament was inspired by the diamond pattern used by Lincoln but was changed to two right ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
