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Spoke
A spoke is one of some number of rods radiating from the center of a wheel (the hub where the axle connects), connecting the hub with the round traction surface. The term originally referred to portions of a log that had been riven (split lengthwise) into four or six sections. The radial members of a wagon wheel were made by carving a spoke (from a log) into their finished shape. A spokeshave is a tool originally developed for this purpose. Eventually, the term spoke was more commonly applied to the finished product of the wheelwright's work than to the materials they used. History The spoked wheel was invented to allow the construction of lighter and swifter vehicles. The earliest physical evidence for spoked wheels was found in the Sintashta culture, dating to 2000 BCE. Soon after this, horse cultures of the Caucasus region used horse-drawn spoked-wheel war chariots for the greater part of three centuries. They moved deep into the Greek peninsula, where they joined w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bicycle Hub
A bicycle wheel is a wheel, most commonly a wire wheel, designed for a bicycle. A pair is often called a wheelset, especially in the context of ready built "off the shelf" performance-oriented wheels. Bicycle wheels are typically designed to fit into the bicycle frame, frame and bicycle fork, fork via Dropout (bicycle part), dropouts, and hold bicycle tires. Invention The first wheel to use the tension in wire wheel, metal spokes was invented by George Cayley, Sir George Cayley to achieve lightness in his 1853 glider. Construction The first bicycle wheels followed the traditions of carriage building: a wooden hub, a fixed steel axle (the bearings were located in the fork ends), wooden spokes and a shrink fitted iron tire. A typical modern wheel has a metal hub, wire tension spokes and a metal or carbon fiber rim which holds a pneumatic rubber tire. Hub A hub is the center part of a bicycle wheel. It consists of an axle, bearing (mechanical), bearings and a hub shell. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spokeshave
A spokeshave is a hand tool used to shape and smooth woods in woodworking jobs such as making cart wheel spokes, chair legs, paddles, bows, and arrows. The tool consists of a blade fixed into the body of the tool, which has a handle for each hand. Historically, a spokeshave was made with a wooden body and metal cutting blade. With industrialization metal bodies displaced wood in mass-produced tools. Being a small tool, a spokeshave is not suited to working large surfaces. History file:Spokeshave dismounted.jpg, left, Spokeshave components The name spokeshave dates back to at least the 16th century, though the early history of the tool is not well documented. The name spokeshave reflects the early use of the tool by Wheelwwheelwrights. The first spokeshaves were made of wood – usually beech – with steel blades, before being largely superseded by the development of metal-bodied spokeshaves in the latter half of the 19th century, though many woodworkers still use wooden spok ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wire Wheel
Wire wheels, wire-spoked wheels, tension-spoked wheels, or "suspension" wheels are wheels whose rims connect to their hubs by wire spokes. Although these wires are considerably stiffer than a similar diameter wire rope, they function mechanically the same as tensioned flexible wires, keeping the rim true while supporting applied loads. The term ''suspension wheel'' should not be confused with vehicle suspension. Wire wheels are used on most bicycles and are still used on many motorcycles. They were invented by aeronautical engineer George Cayley in 1808. Although Cayley first proposed wire wheels, he did not apply for a patent. The first patent for wire wheels was issued to Theodore Jones of London, England on October 11, 1826. Eugène Meyer of Paris, France was the first person to receive, in 1869, a patent for wire wheels on bicycles. Bicycle wheels were not strong enough for cars until the development of tangentially spoked wheels. They rapidly became well establis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wheel
A wheel is a rotating component (typically circular in shape) that is intended to turn on an axle Bearing (mechanical), bearing. The wheel is one of the key components of the wheel and axle which is one of the Simple machine, six simple machines. Wheels, in conjunction with axles, allow heavy objects to be moved easily facilitating movement or transportation while supporting a load, or performing labor in machines. Wheels are also used for other purposes, such as a ship's wheel, steering wheel, potter's wheel, and flywheel. Common examples can be found in transport applications. A wheel reduces friction by facilitating motion by rolling together with the use of axles. In order for a wheel to rotate, a Moment (physics), moment must be applied to the wheel about its axis, either by gravity or by the application of another external force or torque. Terminology The English word '':wikt:wheel, wheel'' comes from the Old English word , from Proto-Germanic language, Proto-Germanic , ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wheel Iran
A wheel is a rotating component (typically circular in shape) that is intended to turn on an axle bearing. The wheel is one of the key components of the wheel and axle which is one of the six simple machines. Wheels, in conjunction with axles, allow heavy objects to be moved easily facilitating movement or transportation while supporting a load, or performing labor in machines. Wheels are also used for other purposes, such as a ship's wheel, steering wheel, potter's wheel, and flywheel. Common examples can be found in transport applications. A wheel reduces friction by facilitating motion by rolling together with the use of axles. In order for a wheel to rotate, a moment must be applied to the wheel about its axis, either by gravity or by the application of another external force or torque. Terminology The English word ''wheel'' comes from the Old English word , from Proto-Germanic , from Proto-Indo-European , an extended form of the root . Cognates within Indo-European in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wheelwright
A wheelwright is a Artisan, craftsman who builds or repairs wooden wheels. The word is the combination of "wheel" and the word "wright" (which comes from the Old English word "''wryhta''", meaning a worker - as also in shipbuilding, shipwright and arkwright). This occupational name became the English surname ''Wright'', and also appears in surnames like ''Cartwright'' and ''Wainwright''. These tradesmen made wheels for carts (cartwheels), wagons (wains), traps and coaches. They also made the wheels, and often the frames, for spinning wheels, and the belt drives of steam powered machinery. First constructing the hub (called the nave), the spokes and the rim segments called felloes, and assembling them all into a unit working from the center of the wheel outwards. Most wheels were made from wood, but other materials have been used, such as bone and horn (anatomy), horn, for decorative or other purposes. Some earlier construction for wheels such as those used in early chariots wer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chariots
A chariot is a type of vehicle similar to a cart, driven by a charioteer, usually using horses to provide rapid motive power. The oldest known chariots have been found in burials of the Sintashta culture in modern-day Chelyabinsk Oblast, Russia, dated to c. 1950–1880 BC and are depicted on cylinder seals from Central Anatolia in Kültepe dated to c. 1900 BC. The critical invention that allowed the construction of light, horse-drawn chariots was the spoked wheel. The chariot was a fast, light, open, two-wheeled conveyance drawn by two or more equids (usually horses) that were hitched side by side, and was little more than a floor with a waist-high guard at the front and sides. It was initially used for ancient warfare during the Bronze and Iron Ages, but after its military capabilities had been superseded by light and heavy cavalries, chariots continued to be used for travel and transport, in processions, for games, and in races. Etymology The word "chariot" comes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tire
A tire (North American English) or tyre (Commonwealth English) is a ring-shaped component that surrounds a Rim (wheel), wheel's rim to transfer a vehicle's load from the axle through the wheel to the ground and to provide Traction (engineering), traction on the surface over which the wheel travels. Most tires, such as those for automobiles and bicycles, are pneumatically inflated structures, providing a flexible cushion that absorbs shock as the tire rolls over rough features on the surface. Tires provide a footprint, called a contact patch, designed to match the vehicle's weight and the bearing on the surface that it rolls over by exerting a pressure that will avoid deforming the surface. The materials of modern pneumatic tires are synthetic rubber, natural rubber, fabric, and wire, along with carbon black and other chemical compounds. They consist of a tire tread, tread and a body. The tread provides Traction (engineering), traction while the body provides containment for a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tension (mechanics)
Tension is the pulling or stretching force transmitted axially along an object such as a string, rope, chain, rod, truss member, or other object, so as to stretch or pull apart the object. In terms of force, it is the opposite of ''compression''. Tension might also be described as the action-reaction pair of forces acting at each end of an object. At the atomic level, when atoms or molecules are pulled apart from each other and gain potential energy with a restoring force still existing, the restoring force might create what is also called tension. Each end of a string or rod under such tension could pull on the object it is attached to, in order to restore the string/rod to its relaxed length. Tension (as a transmitted force, as an action-reaction pair of forces, or as a restoring force) is measured in newtons in the International System of Units (or pounds-force in Imperial units). The ends of a string or other object transmitting tension will exert forces on the objects ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iron
Iron is a chemical element; it has symbol Fe () and atomic number 26. It is a metal that belongs to the first transition series and group 8 of the periodic table. It is, by mass, the most common element on Earth, forming much of Earth's outer and inner core. It is the fourth most abundant element in the Earth's crust, being mainly deposited by meteorites in its metallic state. Extracting usable metal from iron ores requires kilns or furnaces capable of reaching , about 500 °C (900 °F) higher than that required to smelt copper. Humans started to master that process in Eurasia during the 2nd millennium BC and the use of iron tools and weapons began to displace copper alloys – in some regions, only around 1200 BC. That event is considered the transition from the Bronze Age to the Iron Age. In the modern world, iron alloys, such as steel, stainless steel, cast iron and special steels, are by far the most common industrial metals, due to their mechan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hyksos
The Hyksos (; Egyptian language, Egyptian ''wikt:ḥqꜣ, ḥqꜣ(w)-wikt:ḫꜣst, ḫꜣswt'', Egyptological pronunciation: ''heqau khasut'', "ruler(s) of foreign lands"), in modern Egyptology, are the kings of the Fifteenth Dynasty of Egypt (fl. c. 1650–1550 BC). Their seat of power was the city of Avaris in the Nile Delta, from where they ruled over Lower Egypt and Middle Egypt up to Cusae. In the ''Aegyptiaca'', a history of Egypt written by the Greco-Egyptian priest and historian Manetho in the 3rd century BC, the term Hyksos is used ethnically to designate people of probable West Semitic, Levantine origin. While Manetho portrayed the Hyksos as invaders and oppressors, this interpretation is questioned in modern Egyptology. Instead, Hyksos rule might have been preceded by groups of Canaanite peoples who gradually settled in the Nile Delta from the end of the Twelfth Dynasty of Egypt, Twelfth Dynasty onwards and who may have seceded from the crumbling and unstable Egyptia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
