Question

Types of couplings and their applications

Answer 1

Types of Flexible Couplings
Most small to medium size couplings are basically one of three types. 

1.Universal Joints
A universal joint is a linkage consisting of two yokes, one on each shaft, connected by spider as shown on Figure 2. Since universal joints are frequently used, and thee r analysis is complex, a separate section is devoted to them following this section. 
2. Oldham couplings
Oldham Couplings consist of three members. A floating member is trapped by 90 displaced grooves between the two outer members which connect to the drive shafts
Oldham couplings can accommodate lateral shaft misalignments up to 10% of nominal shaft diameters and up to 3 angular misalignments. Lubrication is a problem but can in most applications be overcome by choosing a coupling that uses a wear resistant plastic or an elastomer in place of steel or bronze floating members.

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