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Modular Propeller
Unlike a standard one-piece boat or aircraft propeller, a modular propeller is made up of using a number of replaceable parts, typically: * a set of matched blades; * a propeller hub; and * an end cap to retain the blades and to secure the propeller as a solid unit. Modular propellers may be fitted to aircraft as well as boats. The benefits of a modular propeller are that its specifications (such as blade pitch or propeller diameter) may be altered to suit varying conditions; and it becomes much easier to replace damaged elements, such as a broken blade. Traditional one-piece propellers may be professionally modified to change the blade pitch, but this is not a common or easy option. In contrast, a modular propeller allows changes to be made quickly and easily. A modular propeller may have, for instance, a metal hub but composite blades. One patent A patent is a type of intellectual property that gives its owner the legal right to exclude others from making, using, or selli ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Propeller
A propeller (colloquially often called a screw if on a ship or an airscrew if on an aircraft) is a device with a rotating hub and radiating blades that are set at a pitch to form a helical spiral which, when rotated, exerts linear thrust upon a working fluid such as water or air. Propellers are used to pump fluid through a pipe or duct, or to create thrust to propel a boat through water or an aircraft through air. The blades are specially shaped so that their rotational motion through the fluid causes a pressure difference between the two surfaces of the blade by Bernoulli's principle which exerts force on the fluid. Most marine propellers are screw propellers with helical blades rotating on a propeller shaft (ship), propeller shaft with an approximately horizontal axis. History Early developments The principle employed in using a screw propeller is derived from sculling. In sculling, a single blade is moved through an arc, from side to side taking care to keep presenting the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arplast Helice
Arplast Helice is a former French manufacturer of propellers for light aircraft and microlights. The company was based at Gargas, France. The company appears to have been wound up on 29 April 2015. The firm's main product was the composite Composite or compositing may refer to: Materials * Composite material, a material that is made from several different substances ** Metal matrix composite, composed of metal and other parts ** Cermet, a composite of ceramic and metallic materials ... 3-bladed "Ecoprop", which can be ground-adjustable, in-flight adjustable, or automatically folding. The Ecoprop modular propellers are lightweight, have a very slim profile and are very efficient. Also, the firm once produced its own microlight aircraft, the Arplast Micro'B. See also Le Dauphiné article - http://www.ledauphine.com/economie-et-finance/2013/12/03/le-concepteur-d-helices-en-carbone-arplast-se-diversifie References {{aero-stub Propellers ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ground-adjustable Propeller
A ground-adjustable propeller is a simple type of aircraft variable-pitch propeller where the blade angle can be adjusted between pre-set limits of fine and coarse pitch.Crane, Dale: ''Dictionary of Aeronautical Terms, third edition'', page 86. Aviation Supplies & Academics, 1997. As its name implies, a ground-adjustable propeller may be adjusted only when the aircraft is on the ground and when the engine is not running. To adjust the propeller, the blades are loosened in the hub, a new angle set and then the hub tightened. Ground-adjustable propellers, which tend to be found on light aircraft and very light aircraft, are much cheaper and lighter in weight than in-flight-adjustable propellers. Although a ground-adjustable propeller is much less versatile than an in-flight-adjustable equivalent, nevertheless, compared to a fixed pitch propeller, a ground-adjustable propeller means that pitch changes can be made on the ground to optimise the aircraft for current payload and fly ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Blade Pitch
Blade pitch or simply pitch refers to the angle of a blade in a fluid. The term has applications in aeronautics, shipping, and other fields. Aeronautics In aeronautics, blade pitch refers to the angle of the blades of an aircraft propeller or helicopter rotor. Blade pitch is measured relative to the aircraft body. It is usually described as "fine" or "low" for a more vertical blade angle, and ,# "coarse" or "high" for a more horizontal blade angle. * i n Blade pitch is normally described as a ratio of forward distance per rotation assuming no slip. Blade pitch acts much like the gearing of the final drive of a car. Low pitch yields good low speed acceleration (and climb rate in an aircraft) while high pitch optimizes high speed performance and fuel economy. It is quite common for an aircraft to be designed with a variable-pitch * propeller, to give maximum thrust over a larger speed range. A fine pitch would be used during take-off and landing, whereas a coarser pitch is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Composite Material
A composite material (also called a composition material or shortened to composite, which is the common name) is a material which is produced from two or more constituent materials. These constituent materials have notably dissimilar chemical or physical properties and are merged to create a material with properties unlike the individual elements. Within the finished structure, the individual elements remain separate and distinct, distinguishing composites from mixtures and solid solutions. Typical engineered composite materials include: * Reinforced concrete and masonry *Composite wood such as plywood * Reinforced plastics, such as fibre-reinforced polymer or fiberglass * Ceramic matrix composites ( composite ceramic and metal matrices) *Metal matrix composites *and other advanced composite materials There are various reasons where new material can be favoured. Typical examples include materials which are less expensive, lighter, stronger or more durable when compared with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Patent
A patent is a type of intellectual property that gives its owner the legal right to exclude others from making, using, or selling an invention for a limited period of time in exchange for publishing an enabling disclosure of the invention."A patent is not the grant of a right to make or use or sell. It does not, directly or indirectly, imply any such right. It grants only the right to exclude others. The supposition that a right to make is created by the patent grant is obviously inconsistent with the established distinctions between generic and specific patents, and with the well-known fact that a very considerable portion of the patents granted are in a field covered by a former relatively generic or basic patent, are tributary to such earlier patent, and cannot be practiced unless by license thereunder." – ''Herman v. Youngstown Car Mfg. Co.'', 191 F. 579, 584–85, 112 CCA 185 (6th Cir. 1911) In most countries, patent rights fall under private law and the patent holder ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Propellers
A propeller (colloquially often called a screw if on a ship or an airscrew if on an aircraft) is a device with a rotating hub and radiating blades that are set at a pitch to form a helical spiral which, when rotated, exerts linear thrust upon a working fluid such as water or air. Propellers are used to pump fluid through a pipe or duct, or to create thrust to propel a boat through water or an aircraft through air. The blades are specially shaped so that their rotational motion through the fluid causes a pressure difference between the two surfaces of the blade by Bernoulli's principle which exerts force on the fluid. Most marine propellers are screw propellers with helical blades rotating on a propeller shaft with an approximately horizontal axis. History Early developments The principle employed in using a screw propeller is derived from sculling. In sculling, a single blade is moved through an arc, from side to side taking care to keep presenting the blade to the water at t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Water Transport
Maritime transport (or ocean transport) and hydraulic effluvial transport, or more generally waterborne transport, is the transport of people ( passengers) or goods (cargo) via waterways. Freight transport by sea has been widely used throughout recorded history. The advent of aviation has diminished the importance of sea travel for passengers, though it is still popular for short trips and pleasure cruises. Transport by water is cheaper than transport by air, despite fluctuating exchange rates and a fee placed on top of freighting charges for carrier companies known as the currency adjustment factor. Maritime transport accounts for roughly 80% of international trade, according to UNCTAD in 2020. Maritime transport can be realized over any distance by boat, ship, sailboat or barge, over oceans and lakes, through canals or along rivers. Shipping may be for commerce, recreation, or military purposes. While extensive inland shipping is less critical today, the major ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
