A belt used to transmit power between two shafts.
Flat Belt Drive
Flat belts running on smooth wheels.
Toothed Belt Drive
The toothed belt is very efficient and does not allow any slip.
Toothed belt and sprocket.
Toothed (or Synchronous) belts are always more efficient than V-belt drives, but four considerations preclude them from many applications.
- They make a whirring sound that can be objectionable in some applications.
- They transfer more vibration and shock loads
- Unable to slip when driving loads that are susceptible to jamming.
- They are more sensitive to misalignment, which can cause them to wear unevenly or fail prematurely. This can be a problem where the drive motor or load is on a flexible mount as this can result in misalignment under certain load conditions. Under extreme conditions the flexibility can lead to the belt jumping.
- Pulley diameter affects V-belt efficiency, with larger pulleys producing greater efficiency.
- Narrower or fewer V-belts produce greater efficiency at low torque, while wider or more belts offer higher efficiency at high torque.
- Underbelted or overbelted V-belt drives are inefficient.
- Large variations exist between V-belt drive efficiencies (eg a notched belt).
- V-belt drives may be efficient at the time of installation (achieving 95 to 98% efficiency), but they soon stretch, causing their tension to drop.
- V-belt drives need proper retensioning or efficiency may deteriorate as much as 5% due to belt slippage.
Subjects: Mechanical Engineering