Which side of the belt is tight side if driver pulley is rotating in clockwise direction?
A) Top side
B) Bottom side
C) both sides are tight side
Can you guess from the image?

Answer- B
In the belt drive, when the driver pulley rotates clockwise direction, the bottom side of the belt get pulled towards it and induces tensile force inside the belt. That’s why bottom side get slightly stretched.
There is tension on the top side as well but not equal to the bottom side of the belt drive as it is just pushing the belt towards follower pulley.
More information on belt drive-
Belt drives are used to transmit the power at the speed of 10 m/s to 25 m/s with the help of pulleys of different diameters. Sometimes ropes also used instead of the belt.
It’s a cheaper option than equivalent gear drives, flexible, easy to assemble and maintenance and used from last 200 years.
Belt drives are friction drives, as the power transmission is done through the friction between the pulley and belt.
To understand flat belt drives, one should know the below different aspects of the drives.
- Why belt drives are used?
- How to select belt drive for your application?
- Materials used for belt drives
- Understand shapes or cross section of belt drives
- How to find out the length of the belt?
- Calculate the tension between the belts?
- How much power can belt drive transmit?
- Possible practical problems in the belt drives
For more information on different topics or above topics related to belt drives of mechanical engineering ,download the free app “campuscad” from Google play store.
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