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In the grain trade, a grain elevator is a tower containing a bucket elevator or a pneumatic conveyor, which scoops up grain from a lower level and deposits it in a silo or other storage facility. In most cases, the term "grain elevator" also covers the entire elevator complex (an example of pars pro toto), including receiving and testing offices, weighbridges, storage facilities etc. It may also mean organizations that operate or control several individual elevators, in different locations. In Australia the term ''grain elevator'' refers to the lifting mechanism only (see "usage" below). Prior to the advent of the grain elevator, grain was usually handled in bags rather than in ''bulk'' (large quantities of loose grain). However, Dart's Elevator was a major innovation. It was invented by a merchant named Joseph Dart and an engineer named Robert Dunbar during 1842–43, in Buffalo, New York. Using the steam-powered flour mills of Oliver Evans as their model, they invented the ''marine leg'', which scooped loose grain out of the hulls of ships and elevated it to the top of a ''marine tower''. Early grain elevators and bins were often constructed of framed or cribbed wood, and were prone to fire. Grain elevator bins, tanks and silos are now usually constructed of steel or reinforced concrete. Bucket elevators are used to lift grain to a ''distributor'' or ''consignor'', from where it falls through spouts and/or conveyors and into one of a number of bins, silos or tanks in a facility. When desired, silos, bins and tanks are emptied by gravity flow, sweep augers and conveyors. As grain is emptied from bins, tanks and silos it is conveyed, blended and weighted into trucks, railroad cars or barges, and shipped to grain wholesalers, exporters and/or local end-users, such as flour mills, breweries and ethanol or alcohol distilleries. ==Usage and definitions== In Australian English, the term "grain elevator" is reserved for elevator towers, while a receival and storage building or complex is distinguished by the formal term receival point or as a "wheat bin" or "silo". Large-scale grain receival, storage and logistics operations are known in Australia as bulk handling. In Canada, the term "grain elevator" is used to refer to a place where farmers sell grain into the global grain distribution system, and/or a place where the grain is moved into rail cars or ocean-going ships for transport. Specifically there are several types of grain elevators under Canadian law, defined in the ''Canadian Grain Act'', Section 2. *''Primary elevators'' (called "country elevators" before 1971) receive grain directly from producers for storage, or forwarding, or both. *''Process elevators'' (called "mill elevators" before 1971) receive and store grain for direct manufacture or processing into other products. *''Terminal elevators'' receive grain on or after official inspection and weighing and clean, store, and treat grain before moving it forward. *''Transfer elevators'' (including "Eastern elevators" from the pre-1971 classification) transfer grain that has been officially inspected and weighed at another elevator. In the Eastern Division, transfer elevators also receive, clean, and store eastern or foreign grain. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「grain elevator」の詳細全文を読む スポンサード リンク
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