Coaxial dual-rotor helicopter

Abstract

The invention discloses a coaxial dual-rotor helicopter, which includes a rotor shaft mounted at the upper part of a helicopter body and including an outer rotating shaft and an inner rotating shaft. An upper rotor and a lower rotor are arranged on the rotor shaft; the inner rotating shaft and the outer rotating shaft are connected mutually through a bearing; the upper rotor is mounted on the inner rotating shaft; the lower rotor is mounted on the outer rotating shaft; and the lengths of blades on the upper rotor are smaller than that of blades on the lower rotor. The upper rotor is provided with four blades; and the lower rotor is provided with three blades. Due to the adoption of the technical scheme, the structure is simple; the lengths, the number, the rotating speed and the material of the blades on the upper rotor are improved substantively, so that the structure is simple to operate, and the risk of blade collision caused by upper and lower rotor interference can be avoided; and meanwhile, two rotors have smaller parasite area, thereby improving the ascending power, the maximum level speed and the combination properties of the helicopter.

Description

technical field [0001] The invention belongs to the technical field of aviation aircraft and relates to the technology of helicopters, more specifically, the invention relates to a coaxial double-rotor helicopter. Background technique [0002] Helicopter is a kind of aircraft that generates lift and propulsion by rotor and flies. Compared with fixed-wing aircraft, its important feature is that helicopter can realize hovering in the air. There are two main types of single-rotor helicopters and twin-rotor helicopters: [0003] Single-rotor helicopters generally use a tail rotor to counteract the reactive torque generated by the main rotor. A prominent problem of single-rotor helicopters with tail rotors is their own instability. Single-rotor helicopters have a large moment of inertia around the rotor axis, and generally rely entirely on the tail rotor to balance the reaction torque. The tail rotor is the biggest challenge to the flight safety of single-rotor helicopters. If...

AI Technical Summary

Problems solved by technology

[0006] The main disadvantage of the coaxial twin-rotor helicopter is the complicated control mechanism

Moreover, due to the asymmetric lift generated by the forward and backward blades during flight, the rotation planes of the upper and lower rotors may meet on one side and cause the blades to collide.

In addition, the waste resistance area of ​​the two rotors is relatively large, which limits the maximum level flight speed of the helicopter

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