Home List your patent My account Help Support us

A helicopter rotor arrangement with offset hubs

[Category : - DESIGN PATENTS]
[Viewed 1543 times]

ABSTRACT: This is a conventional helicopter with a tail rotor but with two hubs separated at an equal distance from the mast using a non-flexible tube or bar. The blades meet the air tangentially unlike a conventional radial rotor blade.
Just like conventional two bladed rotor, blades are free to flap up and down and they can be rotated around their span axis (pitching) to increase/decrease the lift. The pitch of the blades is controlled by a swash-plate mechanism as used in a conventional helicopter but there are parallel horns of unequal lengths in each direction.
Tilting the swash-plate causes a cyclic, one per revolution increase and decrease of the pitch when the blades are revolving. This gives more lift on one side of the rotor disc, and a less lift on the other side. The dissymmetry of lift, along with gyroscopic effect tilts the rotor disc and the thrust vector tilts accordingly.

BACKGROUND: With the increase in payload in a semi-rigid rotor helicopters, there is a requirement of increase in length and width of rotor blade (i.e., a change in the aspect ratio of the rotor blade). The decrease in aspect ratio increases drag and increase in blade length increases both drag and blade tip velocity exceeding the speed of sound. To overcome this challenge, more blades with good aspect ratio is required.

CONCLUSION: This disclosure relates to vertical takeoff and landing (VTOL) rotorcraft, in general, and in particular, to a high speed, low drag, low maintenance, stiff in-plane and/or soft in-plane rotor head for a helicopter that enables four or more rotor blades to be used per rotor.

Patent publications:

No publication

Asking price:

Make an offer

Rate this patent

Great invention
Liked: 1 times

Viewed: 1543 times

Seller:

aik010879 (India)

Ask a question
or start a negotiation

Contact the seller

Share on social media