Pulley Changes The Direction Of Force

The pulley is a small wheel with grooves on the periphery and capable of rotating around an axis. A simple machine that can rotate around the central axis is composed of a grooved disc that can rotate around the central axis and a flexible cable (rope, tape, steel cable, chain, etc.) that crosses the disc is called a pulley.

In mechanics, a typical pulley is a round wheel that can rotate around a central axis. There are grooves on the circumferential surface of the round wheel, the rope is wound around the groove, and either end of the rope is pulled hard, the friction between the rope and the round wheel will cause the round wheel to rotate around the central axis.

The pulley is actually a deformable and rotatable lever. The main function of the pulley is to pull the load, change the direction of force, transmit power and so on. A machine composed of multiple pulleys is called a "pulley block" or "complex pulley". The pulley block has greater mechanical benefits and can pull heavier loads. The pulley can also be a component of a chain drive or a belt drive, transmitting power from one rotating shaft to another.

According to whether the position of the central axis of the pulley is moving, the pulleys can be divided into "fixed pulley" and "moving pulley"; the central axis of the fixed pulley is fixed and the central axis of the movable pulley can be moved. Each has its own advantages and disadvantages. The fixed pulley and the movable pulley can be assembled together to form a pulley block, which not only saves effort, but can also change the direction of force.