Structure and assembling technology of propeller blade connecting joint

Abstract

The invention belongs to the technical field of structural design and assembling technologies of main propeller hubs of helicopters, and particularly relates to a structure and assembling technology of a propeller blade connecting joint. At present, one structure is to assemble and mount a lining with a large protruding shoulder into a hole through the temperature difference, the other structure is to assemble and mount a straight lining into the hole through the temperature difference, and then a large gasket is bonded to the hole end face through an adhesive agent. The linings of the two connecting joints adopt the mode of temperature difference assembly, initial damage of the inner surface of the hole has uncertainty, binding force of the hole and the lining is small, and the hole and the lining are prone to generating fretting wear after the hole is subjected to force. According to the structure of the propeller blade connecting joint, a lining is mounted in a connecting hole, thelining is provided with a protruding shoulder, the lining is mounted in the connecting hole through a secondary extruding strengthening method, the lining is used for transmitting the force, and the width of the protruding shoulder of the lining is smaller than 10 mm; and a guiding gasket is arranged on the periphery of the protruding shoulder, the easily occurred problem of sliding of the liningcan be avoided, and meanwhile, the problem of upwarp by excessively extruding strengthening assembly of the protruding shoulder is solved.

Description

technical field [0001] The invention belongs to the technical field of structural design and assembly of a main rotor hub of a helicopter, and in particular relates to a structure and an assembly process of a blade connecting joint. Background technique [0002] At present, the newly developed main propeller hub of the helicopter adopts a spherical flexible structure, and the propeller and the support arm are connected by a propeller pin. The shimmy and torsional force are the bottlenecks of the life of the support arm. [0003] At present, there are mainly two structures, one is that the large shoulder bush is installed in the hole through temperature difference assembly, such as figure 1 A bushing 3 is installed in the connecting hole 4 of the paddle joint, and the shoulder of the bushing 3 has a force transmission area 2 and a guiding area 1. The force-bearing and force-transmitting part of the vibration; the force-transmitting area 2 is in contact with the blade, and i...

AI Technical Summary

Problems solved by technology

The bumping of the shoulder during the installation of the propeller may cause loosening or fretting of the large shoulder bushing, and at the same time, the bumping damage is not easy to replace, thus affecting the life of the hole, reliability and structural maintainability

The other is that the straight bushing is installed in the hole through temperature difference assembly, and then the large gasket is bonded to the end face of the hole with an adhesive, such as figure 2 , the bushing is a straight bushing, and the force transmission gasket and the guide gasket are combined into a large gasket. In the actual use process, the straight bush often has the bushing slippage, and the large gasket is degummed and falls off after being stressed, which affects the hole. Long life and reliability, poor maintainability

[0004] The bushings of these two connection joints are assembled by temperature difference, and the temperature difference assembly is easy to cause initial damage to the inner surface of the hole and has uncertainty, the bonding force between the hole and the bush is small, and the hole and the bush are easy to bear after the hole is stressed. Fretting wear occurs, reducing the life and reliability of the hole

All have certain flaws, which can no longer meet the requirements of the new generation of helicopters for arm life, reliability and maintainability, and have become uncertain factors affecting flight safety and attendance

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