Though the Browning brand is known for their premium quality belts and other industrial components, those belts rely on Browning pulleys to operate as they should. But what is a pulley exactly? A pulley is a wheel on an axle or shaft that is designed to support movement and change of direction of a taut belt or cable, or transfer power between the shaft and the belt. A pulley may have a groove or grooves between flanges around its circumference to locate the cable or belt, and the drive element of a pulley system can be a rope, cable, belt, or chain.
Types of Pulley Systems
Pulleys are one of the six simple machines, and a tool created to make work easier. These simple machines– pulleys, wheel and axle, inclined plane, the wedge, the screw, and the lever– were some of mankind’s earliest discoveries, and they have drastically changed the way we approach problems. When it comes to pulleys– specifically Browning pulleys– there are several different types of pulley systems that are used in different circumstances and applications, and they are as follows:
The most basic types of pulleys are simply made from a wheel and a rope or cord. The rim of the wheel is grooved and the rope, or cord, fits into that groove so that when you pull either up or down on the rope, the wheel turns. The whole purpose of this is to make easier work of moving an object, because pulling a rope downward requires less energy and force than lifting a heavy object upward. That said, a single pulley will not affect the amount of work necessary to move an object very much. For this reason pulleys are usually used in pairs, or combined to form pulley systems.
Fixed Pulley Systems
Another type is the fixed pulley system. In a fixed pulley system, pulleys are immobilized, generally attached to a wall, ceiling, or other framework. In this type, the load moves up or down with the rope, while the pulleys remain stationary. Of course, there are advantages and disadvantages to the fixed pulley system. The fixed pulley changes the direction of force, but not the amount of force required. In fact, the fixed pulley is the only one that requires more effort than the load itself. It requires far more effort to move the load than a movable or compound pulley system; however, the pulley does not have to be pushed or pulled up and down.
Moveable Pulley Systems
On to moveable pulley systems. In this type, the pulley is attached to the load rather than to a wall or framework, allowing the pulley to move with the load. The advantage here is that less work is required to move the load; however, the movable pulley has its disadvantages too. In a movable pulley system, the pulley itself must be pushed or pulled up and down, meaning its own weight is added to the existing load.
Compound Pulley System
A compound pulley system features a combination of fixed and movable pulleys that forms a block and tackle. A block and tackle can have several pulleys mounted on the fixed and moving axles, further increasing the mechanical advantage of the system itself. Compound pulley systems are the most widely used type of system, and it’s obvious as to why. The effort required to move a load rigged to a compound pulley system is less than half of the original load. In other words, the compound pulley system succeeds in reducing the load by more than half. The disadvantage to using a compound pulley system is that with each pulley added, both the length of rope necessary and the distance that the rope must travel inevitably increase.
ProSource Industrial carries the complete line of Browning V-belts, pulleys, and sheaves. Maybe you need a specific trusted V-belt for your drive, or need to know more about the different Browning sheaves available, our team can help you find the right Browning pulley for your application. Peruse our vast Browning pulley catalog today. Whether you need a pulley for a new application or you need to change the speed on an existing belt drive application, our team can help you find what you need.