Belts are a superb solution for power transmission between shafts that are not axially aligned. Belts run smoothly with little noise or vibrations, and they cushion motors and bearings against load changes. They need no lubrication and require little maintenance. They have very high efficiency, usually around 95% and up to 98%. When toothed belts are used they provide excellent precision when a constant ratio between shaft rotational speeds is important.
V-belts were adopted to solve the slippage and alignments problems that are more common with flat belts. They are an excellent combination of traction, bearing load, speed and long life. Their cross section is actually trapezoidal, and this fits into the V on the pulley to provide a self-centering system where the belt cannot slip off. As load increases the belt tends to bed further into the groove which increases friction and therefore torque transmission.
Toothed belts are often used as timing belts and are incredibly efficient. They have teeth that fit into matching teeth on the pulley. They have no slippage, run at a constant speed, and are often used for either indexing or timing purposes. Their main advantage over gears or chains are the lower noise and vibration, and the lack of a need for lubrication.
Bradford Engineering Services can supply off the shelf belts, belts cut to your specific width or spliced to your required length, or can work with you to understand your requirements and recommend appropriate solutions.