A single fixed pulley, like the one in Figure 1(a), has an ideal mechanical advantage of 1 since the effort force (120 N) is equal to the load force (120 N). However, in the single movable pulley (Figure 1(b)), half of the load is supported by the rope attached to the ceiling.

Many types of exercise equipment use pulleys in order to function. Construction pulleys are used in order to lift and place heavy materials. Curtains at a theatre are moved using pulley systems that pull the curtains apart. Blinds on windows operate using a pulley system to move the blinds up and down.

A pulley is similar to another simple machine, the lever. A lever has a fulcrum, or fixed point, around which a bar turns.

The main advantage in the use of pulleys is that the effort becomes less as compared to the normal lifting of the weights. In other words, it reduces the amount of actual force required to lift heavy objects. It also changes the direction of the force applied.

The mechanical advantage of a moveable pulley is 2. This means that a moveable pulley will halve the required force needed to move any object attached to it. This occurs because in a moveable pulley one end of the rope is stationary, which means it absorbs some of the force needed to move the object.

Single movable pulley considered more superior than single fixed pulley because its mechanical advantage is more than 1. Hope this information will clear your doubts about topic.

The movable pulley is used to reduce the amount of input force to lift a load. The most popular system that uses this pulley would be a well. Unlike the fixed pulley, the movable pulley is attached to the load, and is lifted by pulling up on the rope, making it twice as easier to lift a heavy object.

Watch This short introduction on Pulleys. The fixed pulley is a pulley that is attached to a structure and does not move. It’s main purpose is to change the direction of the force needed to lift a load. The effort force needed does not change.

To find the total ratio, use the pulley ratio formula: Ratio = (Radius of Driven Pulley) / (Radius of Drive Pulley) Example: A handcrank is attached to a drive pulley of 2 inches in radius. The belt runs from the drive pulley to a driven pulley.

By changing the diameter of the pulley wheels, speed can be changed. A smaller pulley turning a larger pulley results in the larger one moving more slowly but with more shaft power.

The number of teeth on a gear or sprocket is exactly proportional to the pitch diameter. Therefore, the gear ratio equals the number of teeth on the gear divided by the number of teeth on the driver gear.

If a smaller pulley turns a larger one, the larger one will turn slower, but with more power available at the shaft. If a bigger pulley turns a smaller one, the smaller one will turn much faster than the bigger one but with less power available at the shaft.

What effect does pulley diameter have on efficiency? A larger diameter pulley wheel (aka sheave) is technically more efficient than a smaller diameter pulley. But it’s a trade off: a larger pulley has increased bulk, weight and cost.

Synchronous belt drives require no lubrication, are clean running, are maintenance free, and once installed properly, do not require retensioning.

V-Belts are the most common type of drive belt used for power transmission. Their primary function is to transmit power from a primary source, like a motor, to a secondary driven unit. They provide the best combination of traction, speed transfer, load distribution, and extended service life.