What is the function of a coupling in machinery?

The function of a coupling in machinery is to connect two shafts while allowing for misalignment. Couplings are essential components in mechanical systems as they transmit torque and rotational motion between shafts while accommodating some degree of misalignment that may occur due to manufacturing tolerances, thermal expansion, or operational vibrations. This flexibility helps prevent excessive wear and damage to the shafts and connected equipment.

By allowing for misalignment, a coupling helps ensure smooth operation and prolongs the life of the machinery. This capability is crucial in applications where precise alignment is challenging to maintain. The other options do not accurately describe the primary function of a coupling—energy creation, speed increase, and noise reduction are influenced by different design elements and mechanisms within machinery, but not directly related to the role of a coupling.