Intelligent periodic supporting rod of helicopter main speed reducer and design method of intelligent periodic supporting rod

Abstract

The invention provides an intelligent periodic stay bar for a main speed reducer of a helicopter and a design method of the intelligent periodic stay bar, the intelligent periodic stay bar is mainly used for noise reduction in a helicopter cabin, the stay bar comprises an outer cylinder and an upper cylinder and a lower cylinder which are arranged in the outer cylinder, the upper cylinder and the lower cylinder are each of a periodic structure formed by connecting multiple layers of rubber and piezoelectric stacks in series, and the upper cylinder and the lower cylinder are connected in parallel; the uppermost rubber layer of the upper cylinder is connected with the top of the outer cylinder, the lowermost rubber layer of the upper cylinder is connected with the uppermost rubber layer of the lower cylinder through a connecting metal block, and the lowermost rubber layer of the lower cylinder is connected with the bottom of the outer cylinder; an upper thin-wall circular tube is arranged in the upper cylinder, one end of the upper thin-wall circular tube is in contact with the connecting metal block, and the other end of the upper thin-wall circular tube is connected with an upper connecting joint; a lower thin-wall round pipe is arranged at the bottom of the lower cylinder, and the bottom of the lower thin-wall round pipe is connected with a lower connector. The vibration isolation performance of the supporting rod can be enhanced, the size and the mass of the periodic structure can be reduced, the broadband control capacity is greatly improved, and the driving power needed by an actuator for active control is smaller.

Description

technical field [0001] The invention relates to the technical field of noise control in a helicopter cabin, in particular to an intelligent periodic strut of a helicopter main reducer and a design method thereof. Background technique [0002] The main reducer strut is a connection structure between the helicopter's main reducer and the body. Since most of them are rigid connections, gear meshing vibrations are transmitted to the airframe without attenuation, causing noise in the helicopter cabin. Therefore, the purpose of noise reduction in the cabin can be achieved by the vibration isolation design of the main reducing strut. There are two main methods currently used. [0003] One is to embed several periodic structures composed of metal / rubber in the main reducer strut. Its noise reduction mechanism is to use the broadband vibration reduction characteristics of the periodic structure to prevent the vibration of the main reducer from being transmitted to the body, so as ...

AI Technical Summary

Problems solved by technology

Although this method is effective in controlling the multi-frequency harmonic vibration generated by the meshing of several gears, the broadband control effect is limited.

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