Pulley

Pulley
Pulley Pul"ley, n.; pl. {Pulleys}. [F. poulie, perhaps of Teutonic origin (cf. {Poll}, v. t.); but cf. OE. poleine, polive, pulley, LL. polanus, and F. poulain, properly, a colt, fr. L. pullus young animal, foal (cf. {Pullet}, {Foal}). For the change of sense, cf. F. poutre beam, originally, a filly, and E. easel.] (Mach.) A wheel with a broad rim, or grooved rim, for transmitting power from, or imparting power to, the different parts of machinery, or for changing the direction of motion, by means of a belt, cord, rope, or chain. [1913 Webster]

Note: The pulley, as one of the mechanical powers, consists, in its simplest form, of a grooved wheel, called a sheave, turning within a movable frame or block, by means of a cord or rope attached at one end to a fixed point. The force, acting on the free end of the rope, is thus doubled, but can move the load through only half the space traversed by itself. The rope may also pass over a sheave in another block that is fixed. The end of the rope may be fastened to the movable block, instead of a fixed point, with an additional gain of power, and using either one or two sheaves in the fixed block. Other sheaves may be added, and the power multiplied accordingly. Such an apparatus is called by workmen a {block and tackle}, or a {fall and tackle}. See {Block}. A single fixed pulley gives no increase of power, but serves simply for changing the direction of motion. [1913 Webster]

{Band pulley}, or {Belt pulley}, a pulley with a broad face for transmitting power between revolving shafts by means of a belt, or for guiding a belt.

{Cone pulley}. See {Cone pulley}.

{Conical pulley}, one of a pair of belt pulleys, each in the shape of a truncated cone, for varying velocities.

{Fast pulley}, a pulley firmly attached upon a shaft.

{Loose pulley}, a pulley loose on a shaft, to interrupt the transmission of motion in machinery. See {Fast and loose pulleys}, under {Fast}.

{Parting pulley}, a belt pulley made in semicircular halves, which can be bolted together, to facilitate application to, or removal from, a shaft.

{Pulley block}. Same as {Block}, n. 6.

{Pulley stile} (Arch.), the upright of the window frame into which a pulley is fixed and along which the sash slides.

{Split pulley}, a parting pulley. [1913 Webster]


The Collaborative International Dictionary of English. 2000.

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  • Pulley — ist eine US amerikanische Melodic Hardcore Band aus Kalifornien. Sie sind seit der Gründung Anfang der 1990er Jahre bei dem Plattenlabel Epitaph Records unter Vertrag. Musikalisch bieten sie seit jeher Punkrock, wobei Pulleys Art von Punkrock… …   Deutsch Wikipedia

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  • Pulley — Pul ley, v. t. To raise or lift by means of a pulley. [R.] Howell. [1913 Webster] …   The Collaborative International Dictionary of English

  • pulley — The noun has the plural form pulleys, and the verb (meaning ‘to work with a pulley’) has inflected forms pulleys, pulleyed, pulleying …   Modern English usage

  • pulley — early 14c., from O.Fr. polie (mid 12c.), from M.L. poliva, from Medieval Gk. *polidia, pl. of *polidion little pivot, dim. of Gk. polos pivot, axis (see POLE (Cf. pole) (2)) …   Etymology dictionary

  • pulley — ► NOUN (pl. pulleys) ▪ a wheel with a grooved rim around which a rope, chain, or belt passes, used to raise heavy weights. ORIGIN Old French polie, probably ultimately from Greek polos pivot, axis …   English terms dictionary

  • pulley — [pool′ē] n. pl. pulleys [ME poley < OFr polie < ML poleia < poledia < MGr * polidion, dim. of polos, pivot, windlass, axis: see WHEEL] 1. a small fixed wheel, sometimes turning in a block, with a grooved rim in which a rope or chain… …   English World dictionary

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  • pulley — [1] A grooved wheel carrying a string, rope, chain, or belt which turns the wheel. [2] Flat wheel with a V groove. When attached to a drive and drive members, the pulley provides a means for driving the compressor. See camshaft pulley crankshaft… …   Dictionary of automotive terms

  • pulley — pulleyless, adj. /pool ee/, n., pl. pulleys. 1. a wheel, with a grooved rim for carrying a line, that turns in a frame or block and serves to change the direction of or to transmit force, as when one end of the line is pulled to raise a weight at …   Universalium

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