Though one might not think about gears as being flexible, gear couplings are extremely much regarded as a versatile coupling. A gear coupling can be a mechanical gadget designed to transmit Chain torque between two shafts that aren’t collinear. The coupling typically includes two flexible joints, one set to each shaft. These joints are often connected by a third shaft called the spindle.
Each joint generally consists of a 1:1 equipment ratio internal/exterior gear set. The tooth flanks and external size of the exterior gear are crowned to allow for angular displacement between the two gears. Mechanically, the gears are equivalent to rotating splines with altered profiles. They are known as gears due to the relatively 
large size of one’s teeth. Gear couplings are generally limited by angular misalignments of 4 to 5°.
Gear couplings ordinarily come in two variations, flanged sleeve and continuous sleeve. Flanged equipment couplings contain short sleeves surrounded by a perpendicular flange. One sleeve is normally positioned on each shaft so the two flanges fall into line in person. A series of screws or bolts in the flanges keep them together. Continuous sleeve equipment couplings feature shaft ends coupled jointly and abutted against each other, which are after that enveloped by a sleeve. Generally, these sleeves are made of metal, but they can also be made of Nylon.
Single joint equipment couplings are used to connect two nominally coaxial shafts. In this application these devices is named a gear-type flexible, or versatile coupling. The single joint allows for minimal misalignments such as installation mistakes and changes in shaft alignment because of operating circumstances. These kinds of gear couplings are usually limited by angular misalignments of 1/4 to 1/2°.