Machine en forme de roue, dont la circonférence est creusée en demi-cercle, et sur laquelle passe une corde pour élever ou pour descendre des fardeaux.
ETYM French poulie, perhaps of Teutonic origin.
A simple machine consisting of a wheel with a groove in which a rope can run to change the direction or point of application of a force applied to the rope; SYN. pulley-block, block.
Simple machine consisting of a fixed, grooved wheel, sometimes in a block, around which a rope or chain can be run. A simple pulley serves only to change the direction of the applied effort (as in a simple hoist for raising loads). The use of more than one pulley results in a mechanical advantage, so that a given effort can raise a heavier load.
The mechanical advantage depends on the arrangement of the pulleys. For instance, a block and tackle arrangement with three ropes supporting the load will lift it with one-third of the effort needed to lift it directly (if friction is ignored), giving a mechanical advantage of 3.
ETYM Old Eng. takel, akin to lg. and Dutch takel, Dan. takkel, Swed. tackel; perhaps akin to Eng. taw, v.t, or to take.r />
1. A set of the equipment used in a particular activity; gear.
2. A ship's rigging; an assemblage of ropes and pulleys arranged to gain mechanical advantage for hoisting and pulling.
3. A position on the line of scrimmage.