Winch

Winch

A winch is a mechanical device that is used to pull in (wind up) or let out (wind out) or otherwise adjust the "tension" of a rope or wire rope (also called "cable" or "wire cable"). In its simplest form it consists of a spool and attached hand crank. In larger forms, winches stand at the heart of machines as diverse as tow trucks, steam shovels and elevators. The spool can also be called the winch drum. More elaborate designs have gear assemblies and can be powered by electric, hydraulic, pneumatic or internal combustion drives. Some may include a solenoid brake and/or a mechanical brake or ratchet and pawl device that prevents it from unwinding unless the pawl is retracted.

Applications

Besides industrial applications (e.g. in cranes), winches are used for towing cars, boats, or gliders. There are several winches on almost every boat or ship where they are used to pull anchor or mooring lines, halyards, and sheets.

The rope is usually stored on the winch, but a similar machine that does not store the rope is called a capstan. When trimming a line on a sailboat, the crew member turns the winch handle with one hand, while tailing (pulling on the loose tail end) with the other to maintain tension on the turns. Some winches have a "stripper" or cleat to maintain tension. These are known as "self-tailing" winches [Mark Smith. The Annapolis Book of Seamanship. 1999 Simon & Schuster] .

Winches are frequently used as elements of backstage mechanics to move scenery in large theatrical productions. Winches are often embedded in the stage floor and used to move large set pieces on and off.

History

The earliest literary reference to a winch can be found in the account of Herodotus of Halicarnassus on the Persian Wars ("Histories" 7.36), where he describes how wooden winches were used to tighten the cables for a pontoon bridge across the Hellespont in 480 B.C. Winches may have been employed even earlier in Assyria. By the 4th century BC, winch and pulley hoists were regarded by Aristotle as common for architectural use ("Mech". 18; 853b10-13). [J. J. Coulton, “Lifting in Early Greek Architecture,” The Journal of Hellenic Studies, Vol. 94. (1974), pp. 1-19 (12)]

The largest electric drive winch in the world is placed on the "Balder", a construction ship.Fact|date=February 2007 It is used as a Mooring Line Deployment Winch with a diameter of 10.5 meter and an SWL (Safe Working Load) of 275 MT.

ee also

* Steam donkey
* [http://knol.google.com/k/mads-gorm-larsen/boat-winch/fpvu60g9z3k1/2# Article about boat winches ]

References


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Look at other dictionaries:

  • Winch — self tailing et sa manivelle sur un voilier de plaisance Pour les articles homonymes, voir Winch (homonymie). Un winch (prononcé [ …   Wikipédia en Français

  • winch — [ win(t)ʃ ] n. m. • 1953; mot angl. ♦ Anglic. Techn. Petit treuil à main (⇒ cabestan), sur un yacht. Des winchs ou des winches. ● winch, winchs ou winches nom masculin (anglais winch) Petit treuil à main sur un yacht, constitué d un …   Encyclopédie Universelle

  • Winch — Winch, n. [OE. winche, AS. wince a winch, a reel to wind thread upon. Cf. {Wink}.] [1913 Webster] 1. A crank with a handle, for giving motion to a machine, a grindstone, etc. [1913 Webster] 2. An instrument with which to turn or strain something… …   The Collaborative International Dictionary of English

  • winch — winch·er; winch·man; winch; …   English syllables

  • winch — [winch] n. [ME winche < OE wince < IE base * weng , to be curved, bowed > WINK] 1. a crank with a handle for transmitting motion, as to a grindstone 2. a machine for hoisting, lowering, or hauling, consisting of a drum or cylinder turned …   English World dictionary

  • Winch — Winch, v. i. [See {Wince}.] To wince; to shrink; to kick with impatience or uneasiness. [1913 Webster] …   The Collaborative International Dictionary of English

  • Winch — Winch, n. A kick, as of a beast, from impatience or uneasiness. Shelton. [1913 Webster] …   The Collaborative International Dictionary of English

  • winch — (n.) O.E. wince, from P.Gmc. *winkjo , from PIE *weng (see WINK (Cf. wink) (v.)). The verb meaning to hoist with a winch is recorded from 1520s …   Etymology dictionary

  • winch — ► NOUN 1) a hauling or lifting device consisting of a rope or chain winding around a horizontal rotating drum, turned by a crank or by motor. 2) the crank of a wheel or axle. ► VERB ▪ hoist or haul with a winch. ORIGIN Old English, «reel,… …   English terms dictionary

  • winch — s.m.inv. ES ingl. {{wmetafile0}} TS mar. particolare tipo di verricello usato nelle moderne imbarcazioni a vela Sinonimi: vinci. {{line}} {{/line}} DATA: 1961. ETIMO: da una voce di orig. germanica …   Dizionario italiano

  • winch — /wintʃ/, it. /wintʃ/ s. ingl. [voce di origine germ.], usato in ital. al masch. (marin.) [macchina semplice per sollevare oggetti pesanti] ▶◀ verricello, vinci …   Enciclopedia Italiana

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