Gear Couplings

Gear couplings also play a very important role in the gear performance. A properly functioning gear coupling is a must for success in any gearing system. Essentially Gear couplings are the mechanical devices that is used for transmission of torque between two shafts that are not coaxial. It consists of a flexible joint that is fixed to each shaft. Next, a third shaft called spindle connects the two joints.

The importance of Gear coupling in a peak gear performance can be gauged from the view point of backlash that the gear coupling shows. The gear teeth in a typical gear coupling displays a high backlash for allowing angular Misalignment. Gear couplings can compensate for the Misalignment through the clearance between the gear teeth.

A properly designed gear couplings is supposed to absorb the misalignment forces. This way more costly, vital and sensitive components can be saved from any harm.

Types of Gear Couplings

Flexible Couplings
The advantages of Flexible couplings makes them a preferred choice for many applications. They offer easy installation, no requirement of lubrication, no maintenance requirements, and noise free operation.

Chain Couplings
Chain couplings though not exactly a gear coupling but operate similarly to a gear coupling. Here Sprockets on each of the shaft end get connected by a roller chain. Loading is also identical as that in chain couplings.

Grid Couplings
Grid couplings typically use corrugated steel grids, which bends to compensate for the loading that is induced by misalignment.

Solid and magnetic coupling
Solid and magnetic couplings does not necessitate the need for lubrication. Solid couplings are essentially rigid structures. They do not compensate for misalignment. They allow two shafts to be connected for the transmission of torque. An example of magnetic coupling is the machine that has bolted hubs keyed onto shafts.

Features of Gear Couplings
An ideal gear coupling should show the following properties:

Misalignment of Gear Coupling
Misalignment can occur as an offset or as an angular displacement taking place on two of the three axes. Though the third axis, that is in the longitudinal direction, is commonly not measured, bit errors typically in this direction can cause constant and tremendous thrust loads in the system. The following image shows different types of Misalignment: