Rotor aircraft tilting hub with reduced drag rotor head and mast
AssigneeCartercopters, L.L.C.
InventorsJay W. Carter, Jr., M. Keith Robinson, George D. Mitchell
Life of this patent
Estimating the term…
Abstract
A rotor aircraft has a tilting hub for cyclic control operated by either a tilting spindle or swash plate mounted to the upper end of the drive shaft. A spinner housing with two separate half portions encloses the hub. The blades of the rotor have root portions that are integrally joined to the separate half portions. During a collective pitch change, the half portions rotate relative to each other, but at advance ratios greater than about 0.7, when the collective can be held constant, the spinner half portions can be in perfect alignment. Concentric control sleeves surround the drive shaft for changing collective pitch as well as cyclic pitch.
Claims20
An aircraft, comprising:
- a fuselage;
- a mast extending upward from the fuselage, terminating in a masthead;
- a pair of rotor blades, each of the blades extending from the masthead along a feathering axis;
- a spinner housing enclosing the masthead, the spinner housing having two half portions that are movable relative to each other about the feathering axis of each of the blades, each of the blades terminating at one of the half portions;
- and
- a collective pitch mechanism that causes each half portion of the spinner housing to twist about its feathering axis in opposite directions relative to each other to change the collective pitch of the blades.
An aircraft, comprising:
- a fuselage;
- a drive shaft extending upward from the fuselage;
- a hub mounted to an upper end of the drive shaft by a gimbal, which allows tilting movement of the hub relative to the drive shaft while rotating in unison with the drive shaft;
- a plurality of rotor blades, each of the blades secured to the hub;
- and
- inner and outer sleeves encircling the drive shaft and rotatable in unison with the drive shaft, the sleeves having upper ends cooperatively engaged with the hub for causing tilting of the hub relative to the drive shaft in response to upward and downward movement of the sleeves relative to each other.
An aircraft, comprising:
- a fuselage;
- a rotatable drive shaft extending upward from the fuselage along a drive shaft axis;
- a hub mounted by a gimbal arrangement to an upper end of the drive shaft for rotation with the drive shaft and tilting movement relative to the drive shaft;
- a spinner housing having two separate half portions, each mounted to an opposite side of the hub;
- a pair of rotor blades, each of the blades having a root portion integrally joined with one of the half portions of the spinner housing for movement therewith;
- a pair of sleeves concentrically mounted around the drive shaft for rotation therewith, each of the sleeves being axially movable relative to each other and to the drive shaft, each of the sleeves being cooperatively engaged with one of the half portions of the spinner housing;
- a sleeve control mechanism that has one mode in which both sleeves move in unison axially relative to the drive shaft to cause the half portions of the spinner housing to twist in opposite directions relative to each other to change a collective pitch of the blades;
- the sleeve control mechanism having another mode in which the sleeves move axially relative to each other and to the drive shaft to tilt the hub and the spinner housing;
- and
- a fairing that extends upward from the fuselage and encloses the sleeves.
Dependencies are inferred from the claim text.