When the Curved-tooth Gear Coupling is lubricated with grease, the space of the coupling will not be filled with grease, and the meshing tooth surface will lack lubrication, resulting in dry wear. Because the teeth of the Curved-tooth Gear Coupling are fixed meshing, which is different from the gear transmission, we usually think that its lubrication is not important. The Curved-tooth Gear Coupling’s teeth lubrication is not in place, resulting in the Curved-tooth Gear Coupling often operates without lubrication, which will lead to oil shortage, tooth wear damage, failure and serious loss of the occluder. During the maintenance of the Curved-tooth Gear Coupling, it must be highly lubricated.
The tooth surface of each gear transmits power through contact, especially under the conditions of high-speed and heavy-load transmission, the force on the tooth surface is large. In the process of power transmission, because the two shafts connected by the coupling have a certain deviation from the neutral, and there is a certain displacement between the contact gear tooth surfaces, resulting in the wear of each gear tooth, the gear coupling generally needs good lubrication, especially under high-speed and heavy-load operation. Because the grease does not have fluidity, the gear teeth are usually extruded in a short time after the coupling is oiled, and the gear teeth are easily damaged in a short time, so it must be added regularly to ensure good lubrication.
When the sleeve size of the Curved-tooth Gear Coupling is incorrect, the meshing force and meshing stiffness not only become nonlinear with torque and dynamic relative displacement, but also have cross stiffness. The calculation results of the dynamic meshing force model are basically the same as the equivalent stiffness model. When the radial stiffness is reduced by two orders of magnitude, the calculation results will be greatly affected. The change of dynamic meshing model is not enough to cause the change of system power characteristics. The angular stiffness of the gear sleeve has a great influence on the vibration characteristics of the system, which needs to be paid enough attention in the actual design, assembly and use.
During the vibration process of the Curved-tooth Gear Coupling, the relative displacement, assembly and use of the inner and outer sleeve teeth, as well as the coupling of the transmission torque, will greatly affect the meshing of the sleeve teeth, thus changing its connection stiffness, and having a great impact on the vibration of the entire aero-engine. Based on the deformation geometric relationship and stress analysis of the Curved-tooth Gear Coupling, the excitation model of the misalignment coupling is derived; Based on the equivalent shaft segment method, the whole system connected by the Curved-tooth Gear Coupling is regarded as a multi-span shaft disk system, in which the Curved-tooth Gear Coupling is simulated with the equivalent shaft segment.
