Transmit power between distant shafts with flexible elements.
Flat and V-belts transmit power by friction with tension ratio T₁/T₂=e^{μθ}; chains and toothed belts avoid slip. Power P=(T₁-T₂)v. Used for longer centre distances than gears. Need tensioners and alignment.
A belt on a small pulley has lower wrap angle, limiting torque.
Belts and chains link shafts that are far apart, and they are simpler and cheaper than gears for many drives.
Transmit power between distant shafts with flexible elements.
Belts and chains link shafts that are far apart, and they are simpler and cheaper than gears for many drives.
Chains handle higher loads and resist slip better, while belts are quieter and need no lubrication, so the choice depends on load, speed and environment.
Slip occurs when the tension is too low or the load exceeds the friction capacity, so the belt must be tensioned correctly.
Typical applications include driving a pump from an engine several metres away, setting the drive ratio for a conveyor on a belt drive and choosing a timing belt for a camshaft that needs exact synchronisation.
Study "Gear trains" first (topic 87 of 106 in Engineering Mechanics). It covers the groundwork this topic builds on.
Capstan equation. Synchronous belts for timing. Chain polygon effect.
A belt on a small pulley has lower wrap angle, limiting torque.
The next topic is "Bearings", which builds directly on this one.
It is classed as Advanced in Engineering Mechanics (topic 88 of 106). It is an advanced topic. It assumes you are comfortable with the intermediate topics in Engineering Mechanics.
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