The gear coupling uses lubrication to form an oil film between the tooth surfaces that are in contact with each other. The tooth 

surfaces are not in direct contact with hard grinding, ensuring that the tooth surfaces will not wear out quickly. During the vibration 

process of the gear coupling, the relative displacement of the inner and outer outer teeth, the misalignment of the inner and outer 

outer teeth caused by assembly and use, and the coupling effect of transmitting torque will greatly affect the meshing situation of 

the inner and outer outer teeth, thereby changing the its connection stiffness. When lubricating a gear coupling with lubricating oil, 

as the lubricating oil can flow, the coupling can rely on the flow of lubricating oil and the rotation of the coupling to throw the 

lubricating oil onto the tooth surface of the gear coupling during operation.

Generally, lubricating oil can be filled into half of the cavity of the gear coupling. In order to ensure that the lubricating oil can regularly 

and well lubricate each gear tooth when the gear coupling is running, the gear coupling must be well prepared. External seal to prevent 

oil leakage. Because the centrifugal force of the high-speed rotating gear coupling is very large, if the outer seal of the coupling is not 

good, the lubricating oil will be thrown out, which will not only affect the normal lubrication of the gear coupling, but also affect production. 

Generally, grease lubrication is used as much as possible, because the gear teeth of the gear coupling are fixedly meshed, unlike gear 

transmission, so its lubrication is not considered important.

In the case of tooth misalignment, the meshing force and meshing stiffness not only change nonlinearly with torque and dynamic relative 

displacement, but also have cross stiffness. The meshing teeth of the inner ring gear of the flange are straight teeth, and the meshing teeth 

of the outer gear sleeve of the flange are drum-shaped teeth, which can provide a certain amount of angular offset compensation. The gear 

coupling uses a meshing pair with hard tooth surfaces to improve its load-bearing capacity. At the same time, increasing the radius of curvature 

in the middle of the drum-shaped teeth can also greatly improve the load-bearing capacity of the coupling. There is a certain deviation in the 

value of the allowable contact stress of the gear coupling. During the process of transmitting power, there is a certain displacement between the 

tooth surfaces of the contacting gear teeth.