Belt drives are generally divided into the following three categories:
Lightweight drive.
Medium drive.
Heavy-duty drive.
Lightweight drives: They are used as agricultural machinery and small machine tools to transmit small forces at a belt speed of approximately 10 m/s.
Medium driving force: They are used to transmit medium forces at belt speeds exceeding 10 m/s but up to 22 m/s, such as machine tools.
Heavy-duty drives: They are used in compressors and generators to transmit large forces at belt speeds exceeding 22 m/s.
There are three basic types of power transmission belts: flat belts, V-belts and timing belts. Misalignment is a common cause of premature belt damage. Power transmission belts have been in use for more than 200 years. The original belt is flat and runs on flat pulleys.
1. Flat belt
Flat belts are also used to transfer power from one shaft to another. The flat belt outputs power through the friction between the belt and the pulley. In a flat belt, the pulleys rotate in the same direction.
They are generally classified as small woven endless belts or high-strength flat belts. Braided endless belts are particularly useful. In this case, since semi-elastic materials are used in the construction, the required vibration on the driven pulley is minimal.
High-strength flat belts are often useful because they eliminate the need for high belt tension to secure the pulleys, thereby reducing the load on the bearings.
The material used for high-strength flat belts is a sticky-resistant abrasive.
2. V belt
V-belts are commonly used in factories and workshops. When two pulleys are very close to each other, a large amount of power must be transferred from one pulley to another.
The V-belt solves the problem of slippage and alignment. Now, it is the original belt for power transmission. They provide the best combination of traction, moving speed, bearing load and longer service life. They are usually endless, and their normal cross-section is roughly trapezoidal in size.
3.Round belt
The round belt is a round cross-section belt designed to run in a pulley with a 60-degree V-groove. The round groove is only suitable for the idler pulley of the guide belt, or when the O-ring type belt is used.
The V-groove transmits torque through palpation, which increases friction. However, round belts are only used for relatively low torque situations, can be purchased in various lengths or cut to certain lengths, and can be connected by staples, metal connectors, gluing or welding. Early sewing machines used belts, which were either fixed to metal staples or glued to metal nails, which worked well.
4. Timing belt
The timing belt is a forward conveyor belt that can track relative movement. The teeth of these belts can be fitted into matching toothed pulleys. When subjected to proper pressure, they will not slip, move at a constant speed, and are usually used to deliver direct motion for sequencing or timing.
They are usually used instead of chains or gears, so they are low noise and do not require a lubricating bath. These belts are often used in automobile camshafts, short timing systems and stepper motors. The timing belt requires the least tension and is the most efficient belt of all belts.
