出典(authority):フリー百科事典『ウィキペディア(Wikipedia)』「2015/12/01 05:37:24」(JST)
A crowbar, wrecking bar, pry bar, or prybar, pinch-bar or sometimes a prise bar, prisebar, and more informally a jimmy, jimmy bar, jemmy or PikiPiki [1] or gooseneck is a tool consisting of a metal bar with a single curved end and flattened points, often with a small fissure on one or both ends for removing nails. In Britain, Ireland, New Zealand and Australia, due to the influence of American TV "crowbar" may occasionally be used loosely for this tool, but it is still mainly used to mean a larger straighter tool, its original English meaning (see digging bar). The term jemmy or jimmy most often refers to the tool when used for burglary.
It is used as a lever either to force apart two objects or to remove nails. Crowbars are commonly used to open nailed wooden crates, remove nails, or pry apart boards. Crowbars can be used as any of the three lever classes but the curved end is usually used as a first-class lever, and the flat end as a second class lever. In mining, crowbars are used to break blasted rocks and to remove loose rock on roof sides and the working face, but not as much in modern mining.
Normally made of medium-carbon steel, they can alternatively be made from titanium, which has the advantages of being lighter and nonmagnetic.
The least expensive, most common crowbars are forged from hexagonal, or sometimes cylindrical stock. More expensive designs may be forged with an I-shaped cross-section shaft.
The accepted etymology[2][3] identifies the first component of the word crowbar with the bird-name "crow", perhaps due to the crowbar’s resemblance to the feet or beak of a crow. The first attestation of the word is circa 1400. [4]They also were called simply crows, or iron crows; William Shakespeare used the term iron crow in many places,[5] including his play Romeo and Juliet, Act 5, Scene 2:
In the 1719 novel by Daniel Defoe, Robinson Crusoe, the protagonist uses crowbars as pickaxes but refers to these tools as iron crows:
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