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 (or drum) attached to a hand crank. Winches are the basis of such machines as tow trucks, steam shovels and elevators. More complex designs have gear assemblies and can be powered by electric, hydraulic, pneumatic or internal combustion drives. It might include a solenoid brake and/or a mechanical brake or ratchet and pawl which prevents it unwinding unless the pawl is retracted.
In physics, tension may be described as the pulling force transmitted axially by the means of a string, a cable, chain, or similar one-dimensional continuous object, or by each end of a rod, truss member, or similar three-dimensional object; tension might also be described as the action-reaction pair of forces acting at each end of said elements. Tension could be the opposite of compression.
A rope is a group of yarns, plies, fibers or strands that are twisted or braided together into a larger and stronger form. Ropes have tensile strength and so can be used for dragging and lifting. Rope is thicker and stronger than similarly constructed cord, string, and twine.
Wire rope is several strands of metal wire twisted into a helix forming a composite "rope", in a pattern known as "laid rope". Larger diameter wire rope consists of multiple strands of such laid rope in a pattern known as "cable laid".
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 BC. 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).
The Greco-Persian Wars were a series of conflicts between the Achaemenid Empire and Greek city-states that started in 499 BC and lasted until 449 BC. The collision between the fractious political world of the Greeks and the enormous empire of the Persians began when Cyrus the Great conquered the Greek-inhabited region of Ionia in 547 BC. Struggling to control the independent-minded cities of Ionia, the Persians appointed tyrants to rule each of them. This would prove to be the source of much trouble for the Greeks and Persians alike.
The Histories of Herodotus is considered the founding work of history in Western literature. Written in 440 BC in the Ionic dialect of classical Greek, The Histories serves as a record of the ancient traditions, politics, geography, and clashes of various cultures that were known in Western Asia, Northern Africa and Greece at that time. Although not a fully impartial record, it remains one of the West's most important sources regarding these affairs. Moreover, it established the genre and study of history in the Western world.
A pontoon bridge, also known as a floating bridge, uses floats or shallow-draft boats to support a continuous deck for pedestrian and vehicle travel. The buoyancy of the supports limits the maximum load they can carry.
The yacht Reliance , American defender of the 1903 America's Cup, was the first racing boat to be fitted with modern winches below decks, in an era when her competitors relied on pulley systems (block and tackle).
Reliance was the 1903 America's Cup defender, the fourth defender from the famous designer Nat Herreshoff, and reportedly the largest gaff-rigged cutter ever built.
The America's Cup, affectionately known as the Auld Mug, is a trophy awarded to the winner of the America's Cup match races between two sailing yachts. One yacht, known as the defender, represents the yacht club that currently holds the America's Cup and the second yacht, known as the challenger, represents the yacht club that is challenging for the cup. The timing of each match is determined by an agreement between the defender and the challenger. The America's Cup is the oldest international sporting trophy. It will next be raced for in the southern summer, in the early part of 2021.
A block and tackle is a system of two or more pulleys with a rope or cable threaded between them, usually used to lift heavy loads.
The rope may be stored on the winch. 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.
A sailboat or sailing boat is a boat propelled partly or entirely by sails smaller than a sailing ship. Distinctions in what constitutes a sailing boat and ship vary by region and maritime culture.
Winches are frequently used as elements of backstage mechanics to move scenery in large theatrical productions. They are often embedded in the stage floor and used to move large set pieces on and off.
Theatrical scenery is that which is used as a setting for a theatrical production. Scenery may be just about anything, from a single chair to an elaborately re-created street, no matter how large or how small, whether the item was custom-made or is the genuine item, appropriated for theatrical use.
Off-road vehicles often carry a winch which may be electrically or hydraulically powered, and is wound with a wire cable. If the vehicle loses traction, the winch is used to pull it back to firmer ground.
An off-road vehicle is considered to be any type of vehicle which is capable of driving on and off paved or gravel surface. It is generally characterized by having large tires with deep, open treads, a flexible suspension, or even caterpillar tracks. Other vehicles that do not travel public streets or highways are generally termed off-highway vehicles, including tractors, forklifts, cranes, backhoes, bulldozers, and golf carts.
Lever winches are winches that use self-gripping jaws instead of spools to move rope or wire through the winch. Powered by moving a handle back and forth, they allow one person to move objects several tons in weight. Brand names include Tirfor and Griphoist.
This is a vertical spool with a ratchet mechanism similar to a conventional winch, but with no crank handle or other form of drive.The line is wrapped around the spool and can be tightened and reeled in by pulling the tail line, the winch takes the load once the pull is stopped with little operator tension needed to hold it. They also allow controlled release of the tension by the operator using the friction of the line around the ratcheted spool. They are used on small sailing boats and dinghies to control sheets and other lines, and in larger applications to supplement and relieve tension on the primary winch mechanisms.
Wakeskate winching is a growing hobby for many watersports enthusiasts. The winch consists of an engine, spool, rope, handle, frame, and some sort of simple transmission. The person being towed walks (or swims) away from the winch and pulls out all of the rope. When the winch is engaged, it pulls the boarder usually between 15 to 25 miles per hour (24 to 40 km/h). The winch may be mounted on the trailer hitch of a vehicle, set into the ground by stakes, or tied to a tree. These winches have been modified for use by skiers and snowboarders in cities.
Gliders are often launched using a winch mounted on a trailer or heavy vehicle. This method is widely used at European gliding clubs, as a cheaper alternative to aerotowing. The engine is usually a large petrol, LPG or diesel, though hydraulic fluid engines and electrical motors are also used. The winch pulls in a 1,000 to 1,600-metre (3,000 to 5,500 ft) cable, made of high-tensile steel wire or a synthetic fibre, attached to the glider. The cable is released at a height of about 400 to 700 metres (1,300 to 2,200 ft) after a short, steep climb.
An air winch, sometimes known as an air hoist or air tugger, is an air-powered version of a winch. It is commonly used for the lifting and the suspension of materials. In the oil and gas, construction, and maritime industries, air winches are frequently preferred to electric, diesel, and hydraulic winches because of their durability, versatility, and safety.
A pulley is a wheel on an axle or shaft that is designed to support movement and change of direction of a taut cable or belt, or transfer of power between the shaft and cable or belt. In the case of a pulley supported by a frame or shell that does not transfer power to a shaft, but is used to guide the cable or exert a force, the supporting shell is called a block, and the pulley may be called a sheave.
A fishing reel is a cylindrical device attached to a fishing rod used in winding and stowing line.
A starter is a device used to rotate (crank) an internal-combustion engine so as to initiate the engine's operation under its own power. Starters can be electric, pneumatic, or hydraulic. In the case of very large engines, the starter can even be another internal-combustion engine.
The windlass is an apparatus for moving heavy weights. Typically, a windlass consists of a horizontal cylinder (barrel), which is rotated by the turn of a crank or belt. A winch is affixed to one or both ends, and a cable or rope is wound around the winch, pulling a weight attached to the opposite end. The oldest depiction of a windlass for raising water can be found in the Book of Agriculture published in 1313 by the Chinese official Wang Zhen of the Yuan Dynasty . The Greek scientist Archimedes was the inventor of the windlass.
A crane is a type of machine, generally equipped with a hoist rope, wire ropes or chains, and sheaves, that can be used both to lift and lower materials and to move them horizontally. It is mainly used for lifting heavy things and transporting them to other places. The device uses one or more simple machines to create mechanical advantage and thus move loads beyond the normal capability of a human. Cranes are commonly employed in the transport industry for the loading and unloading of freight, in the construction industry for the movement of materials, and in the manufacturing industry for the assembling of heavy equipment.
Kite types, kite mooring, and kite applications result in a wide variety of kite control systems. Contemporary manufacturers, kite athletes, kite pilots, scientists, and engineers are expanding the possibilities.
A capstan is a vertical-axled rotating machine developed for use on sailing ships to multiply the pulling force of seamen when hauling ropes, cables, and hawsers. The principle is similar to that of the windlass, which has a horizontal axle.
A Prusik is a friction hitch or knot used to attach a loop of cord around a rope, applied in climbing, canyoneering, mountaineering, caving, rope rescue, ziplining, and by arborists. The term Prusik is a name for both the loops of cord and the hitch, and the verb is "to prusik". More casually, the term is used for any friction hitch or device that can grab a rope. The word is often misspelled as Prussik, Prussick or Prussic, as it is a homophone with the term prussic acid.
A fly system, or theatrical rigging system, is a system of rope lines, blocks (pulleys), counterweights and related devices within a theater that enables a stage crew to fly (hoist) quickly, quietly and safely components such as curtains, lights, scenery, stage effects and, sometimes, people. Systems are typically designed to fly components between clear view of the audience and out of view, into the large opening, known as the fly loft, above the stage.
A windlass is a machine used on ships that is used to let-out and heave-up equipment such as a ship's anchor or a fishing trawl. On some ships, it may be located in a specific room called the windlass room.
In road vehicles, the parking brake, also known as a hand brake or emergency brake (e-brake), is a mechanism used to keep the vehicle securely motionless when parked. Historically, it was also used to help perform an emergency stop should the main hydraulic brakes fail. Parking brakes often consist of a cable connected to two wheel brakes, which is then connected to a pulling mechanism. In most vehicles, the parking brake operates only on the rear wheels, which have reduced traction while braking. The mechanism may be a hand-operated lever, a straight pull handle located near the steering column or a foot-operated pedal located with the other pedals.
High lead logging is a method of cable logging using a spar, yarder and loader. It was developed by Oscar Wirkkala. It is accomplished with two lines (cables) and two winches. The mainline or yarding line extends out from one winch, while a second usually lighter line called the haulback line extends out from the other winch to a 'tail block' or pulley at the tail (back) end of the logging site, and passes through the tail block and connects to the main line. Butt rigging is installed where the two lines join and the logs are hooked to the butt rigging with chokers. The procedure is to wind up the main line and the logs are pulled in, wind up the haulback and the butt rigging is pulled out for more logs or another 'turn'.
The Meillerwagen was a German World War II trailer used to transport a V-2 rocket from the 'transloading point' of the Technical Troop Area to the launching point, to erect the missile on the Brennstand, and to act as the service gantry for fuelling and launch preparation.
USNS Apache (T-ATF-172), fifth United States Navy ship of the name, is the last of the Powhatan class of fleet ocean tugs. Apache was delivered to the U.S. Navy in 1981. She is operated by Military Sealift Command and crewed by 18 civil service mariners (CIVMARS). She is designed to provide the Navy with towing service, and when augmented by Navy divers, assist in the recovery of downed aircraft and ships. There are quarters on board for up to 22 additional personnel.
A come-a-long is a hand operated winch with a ratchet used to pull objects. The drum is wrapped with wire rope. A similar tool that uses a nylon strap is used to straighten trees in Texas, as it straightens gradually over time, therefore not splitting the trunk
Gliding is a recreational activity and competitive air sport in which pilots fly unpowered aircraft known as gliders or sailplanes using naturally occurring currents of rising air in the atmosphere to remain airborne. The word soaring is also used for the sport.
A drawworks is the primary hoisting machinery component of a rotary drilling rig. Its main function is to provide a means of raising and lowering the traveling block. The wire-rope drill line winds on the drawworks drum and over the crown block to the traveling block, allowing the drill string to be moved up and down as the drum turns. The segment of drill line from the drawworks to the crown block is called the "fast line". The drill line then enters the first sheave of the crown block and makes typically 6 to 12 passes between the crown block and traveling block pulleys for mechanical advantage. The line then exits the last sheave on the crown block and is fastened to a derrick leg on the other side of the rig floor. This section of drill line is called the "dead line."
Wire rope spooling-Technology is the technology to prevent wire rope getting snagged when spooled especially in multiple layers on a drum.
A hydraulic jigger is a hydraulically powered mechanical winch.
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