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2. Differential pulley - Wikipedia

   en.wikipedia.org/wiki/Differential_pulley

   A dumb pulley can lift very large masses a short distance. It consists of two fixed pulleys of unequal radii that are attached to each other and rotate together, a single pulley bearing the load, and an endless rope looped around the pulleys. To avoid slippage, the rope is usually replaced by a chain, and the connected pulleys by sprockets.

3. Pulley - Wikipedia

   en.wikipedia.org/wiki/Pulley

   Pulley in oil derrick A hoist using the compound pulley system yielding an advantage of 4. The single fixed pulley is installed on the hoist. The two movable pulleys (joined) are attached to the hook. One end of the rope is attached to the crane frame, another to the winch.

4. Hoist (device) - Wikipedia

   en.wikipedia.org/wiki/Hoist_(device)

   Hoist atop an elevator. A hoist is a device used for lifting or lowering a load by means of a drum or lift-wheel around which rope or chain wraps. It may be manually operated, electrically or pneumatically driven and may use chain, fiber or wire rope as its lifting medium.

5. Block and tackle - Wikipedia

   en.wikipedia.org/wiki/Block_and_tackle

   The mechanical advantage is 2, requiring a force of only 50 N to lift the load. A block and tackle is characterized by the use of a single continuous rope to transmit a tension force around one or more pulleys to lift or move a load. Its mechanical advantage is the number of parts of the rope that act on the load. The mechanical advantage of a ...

6. Treadwheel crane - Wikipedia

   en.wikipedia.org/wiki/Treadwheel_crane

   The Roman Polyspaston crane, from Ancient Greek πολύσπαστον (polúspaston, “compound pulley”), when worked by four men at both sides of the winch, could lift 3000 kg. In case the winch was replaced by a treadwheel, the maximum load even doubled to 6000 kg at only half the crew, since the treadwheel possesses a much bigger ...

7. Crane (machine) - Wikipedia

   en.wikipedia.org/wiki/Crane_(machine)

   The introduction of the winch and pulley hoist soon led to a widespread replacement of ramps as the main means of vertical motion. For the next 200 years, Greek building sites witnessed a sharp reduction in the weights handled, as the new lifting technique made the use of several smaller stones more practical than fewer larger ones.