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Torsion Spring
A torsion spring is a spring that works by twisting its end along its axis; that is, a flexible elastic object that stores mechanical energy when it is twisted. When it is twisted, it exerts a torque in the opposite direction, proportional to the amount (angle) it is twisted. There are various types: *A torsion bar is a straight bar of metal or rubber that is subjected to twisting (shear stress) about its axis by torque applied at its ends. *A more delicate form used in sensitive instruments, called a torsion fiber consists of a fiber of silk, glass, or quartz under tension, that is twisted about its axis. *A helical torsion spring, is a metal rod or wire in the shape of a helix (coil) that is subjected to twisting about the axis of the coil by sideways forces (bending moments) applied to its ends, twisting the coil tighter. *Clocks use a spiral wound torsion spring (a form of helical torsion spring where the coils are around each other instead of piled up) sometimes ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elastic Limit
In materials science and engineering, the yield point is the point on a stress–strain curve that indicates the limit of elastic behavior and the beginning of plastic behavior. Below the yield point, a material will deform elastically and will return to its original shape when the applied stress is removed. Once the yield point is passed, some fraction of the deformation will be permanent and non-reversible and is known as plastic deformation. The yield strength or yield stress is a material property and is the stress corresponding to the yield point at which the material begins to deform plastically. The yield strength is often used to determine the maximum allowable load in a mechanical component, since it represents the upper limit to forces that can be applied without producing permanent deformation. For most metals, such as aluminium and cold-worked steel, there is a gradual onset of non-linear behavior, and no precise yield point. In such a case, the offset yield p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Torsion Bar Suspension
A torsion bar suspension, also known as a torsion spring suspension, is any vehicle suspension that uses a torsion bar as its main weight-bearing spring. One end of a long metal bar is attached firmly to the vehicle chassis; the opposite end terminates in a lever, the torsion key, mounted perpendicular to the bar, that is attached to a suspension arm, a spindle, or the axle. Vertical motion of the wheel causes the bar to twist around its axis and is resisted by the bar's torsion resistance. The effective spring rate of the bar is determined by its length, cross section, shape, material, and manufacturing process. Usage Torsion bar suspensions are used on combat vehicles and tanks like the T-72, Leopard 1, Leopard 2, M26 Pershing, M18 Hellcat, M46/M47/M48 Patton, M60 and the M1 Abrams (many tanks from World War II used this suspension), and on modern trucks and SUVs from Ford, Chrysler, GM, Mitsubishi, Mazda, Nissan, Isuzu, LuAZ, and Toyota. Class 8 truck manufacture ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Compact Disc
The compact disc (CD) is a Digital media, digital optical disc data storage format co-developed by Philips and Sony to store and play digital audio recordings. It employs the Compact Disc Digital Audio (CD-DA) standard and was capable of holding of uncompressed stereo audio. First released in Japan in October 1982, the CD was the second optical disc format to reach the market, following the larger LaserDisc (LD). In later years, the technology was adapted for computer data storage as CD-ROM and subsequently expanded into various writable and multimedia formats. , over 200 billion CDs (including audio CDs, CD-ROMs, and CD-Rs) had been sold worldwide. Standard CDs have a diameter of and typically hold up to 74 minutes of audio or approximately of data. This was later regularly extended to 80 minutes or by reducing the spacing between data tracks, with some discs unofficially reaching up to 99 minutes or which falls outside established specifications. Smaller variants, such ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Digital Camera
A digital camera, also called a digicam, is a camera that captures photographs in Digital data storage, digital memory. Most cameras produced today are digital, largely replacing those that capture images on photographic film or film stock. Digital cameras are now widely incorporated into mobile devices like smartphones with the same or more capabilities and features of dedicated cameras. High-end, high-definition dedicated cameras are still commonly used by professionals and those who desire to take higher-quality photographs. Digital and digital movie cameras share an optical system, typically using a Camera lens, lens with a variable Diaphragm (optics), diaphragm to focus light onto an image pickup device. The diaphragm and Shutter (photography), shutter admit a controlled amount of light to the image, just as with film, but the image pickup device is electronic rather than chemical. However, unlike film cameras, digital cameras can display images on a screen immediately afte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sedan (car)
A sedan (American English) or saloon (British English) is a automobile, passenger car in a three-box styling, three-box configuration with separate compartments for an engine, passengers, and cargo. The first recorded use of ''sedan'' in reference to an automobile body occurred in 1912. The name derives from the 17th-century Litter (vehicle), litter known as a sedan chair, a one-person enclosed box with windows and carried by porters. Variations of the sedan style include the close-coupled sedan, club sedan, convertible sedan, fastback sedan, hardtop sedan, notchback sedan, and sedanet. Definition A sedan () is a car with a closed body (i.e., a fixed metal roof) with the engine, passengers, and cargo in separate compartments. This broad definition does not differentiate sedans from various other car body styles. Still, in practice, the typical characteristics of sedans are: * a Pillar (car), B-pillar (between the front and rear windows) that supports the roof; * two rows of s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Decklid
The trunk (American English) or boot (British English) of a car is the vehicle's main storage or cargo compartment, often a hatch at the rear of the vehicle. It can also be called a tailgate. In Indian English the storage area is known as a dickey (also spelled dicky, dickie, or diggy), and in Southeast Asia as a compartment. Designs The trunk or luggage compartment is most often at the rear of the vehicle. Early designs had an exterior rack on the rear of the vehicle to attach a luggage trunk. Later designs integrated the storage area into the vehicle's body, and eventually became more streamlined. The main storage compartment is normally provided at the end of the vehicle opposite to which the engine is located. Some vehicles have the trunk in front of the passenger compartment, e.g. rear-engined cars like Volkswagen Beetle and Porsche 911, or electric vehicles like Ford F-150 Lightning. This is known as a frunk, a portmanteau of the words "front" and "trunk". The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Garage Door
A garage door is a large door to allow access to a garage that opens either manually or by an electric motor (a garage door opener). Garage doors are frequently large enough to accommodate automobiles and other vehicles. The operating mechanism is usually spring-loaded or counterbalanced to offset the door's weight and reduce the human or motor effort required to operate the door. Less commonly, some garage doors slide or swing horizontally. Doors are made of wood, metal, or fiberglass, and may be insulated to prevent heat loss. Description A typical version of an overhead garage door used in the past would have been built as a one-piece panel. The panel was mounted on each side with an unequal parallelogram-style hinge lifting mechanism. Newer versions of overhead garage doors are now generally built from several panels hinged together that roll along a system of tracks guided by rollers. The weight of the door may be or more but is balanced by either a torsion spring syste ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mousetrap
A mousetrap is a specialized type of animal trap designed primarily to catch and, usually, kill Mouse, mice. Mousetraps are usually set in an indoor location where there is a suspected infestation of rodents. Larger traps are designed to catch other species of animals, such as rats, squirrels, and other small rodents. Types Jaw mousetrap The trap that is credited as the first patented lethal mousetrap was a set of spring-loaded, cast-iron jaws dubbed "Royal No. 1". It was patented on 4 November 1879 by James M. Keep of New York, US patent 221,320. From the patent description, it is clear that this is not the ''first'' mousetrap of this type, but the patent is for this simplified, easy-to-manufacture design. It is the industrial-age development of the Animal trapping#Deadfall traps, deadfall trap, but relying on the force of a wound spring rather than gravity. The jaws are operated by a coiled spring, and the triggering mechanism is between the jaws, where the bait is held. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clothespin
A clothespin (US English) or clothes peg (UK English), also spelled "clothes pin" is a fastener used to hang up clothes for drying, usually on a clothes line. Clothespins come in many different designs. Design During the 1700s laundry was hung on bushes, limbs or lines to dry but no clothespins can be found in any painting or prints of the era. The clothespin for hanging up wet laundry only appears in the early 19th century supposedly patented by Jérémie Victor Opdebec. This design does not use springs, but is fashioned in one piece of wood, with the two prongs part of the peg chassis with only a small distance between them—this form of peg creates the gripping action due to the two prongs being wedged apart and thus squeezing together in that the prongs want to return to their initial, resting state. This form of peg is often fashioned from plastic, or originally, wood. In England, clothes-peg making used to be a craft associated with Romani people, the Romani people, w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Joule
The joule ( , or ; symbol: J) is the unit of energy in the International System of Units (SI). In terms of SI base units, one joule corresponds to one kilogram- metre squared per second squared One joule is equal to the amount of work done when a force of one newton displaces a body through a distance of one metre in the direction of that force. It is also the energy dissipated as heat when an electric current of one ampere passes through a resistance of one ohm for one second. It is named after the English physicist James Prescott Joule (1818–1889). Definition According to the International Bureau of Weights and Measures the joule is defined as "the work done when the point of application of 1 MKS unit of force ewtonmoves a distance of 1 metre in the direction of the force." In terms of SI base units and in terms of SI derived units with special names, the joule is defined as One joule is also equivalent to any of the following: * The work required to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Torsion Constant
The torsion constant or torsion coefficient is a geometrical property of a bar's cross-section. It is involved in the relationship between angle of twist (mechanics), twist and applied torque along the axis of the bar, for a homogeneous linear elastic bar. The torsion constant, together with material properties and length, describes a bar's torsional stiffness. The SI unit for torsion constant is metre, m4. History In 1820, the French engineer A. Duleau derived analytically that the torsion constant of a beam is identical to the second moment of area normal to the section Jzz, which has an exact analytic equation, by assuming that a plane section before twisting remains planar after twisting, and a diameter remains a straight line. Unfortunately, that assumption is correct only in beams with circular cross-sections, and is incorrect for any other shape where warping takes place. For non-circular cross-sections, there are no exact analytical equations for finding the torsion co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
