Helicopter rotor plenum chamber

Claim 1

In a helicopter having a body, a hollow rotor shaft extending upwardly from the body for supporting a set of rotor blades, which rotor blades include a longitudinally oriented cavity terminating in a rearwardly directed orifice, an air pressure source disposed within the body for conveying a flow of air through the hollow rotor shaft and rotor hub system, including a rotor hub, for transmitting the flow of air through the hollow rotor shaft into the longitudinal cavity of each of the rotor blades, said rotor hub system comprising: A. support means concentrically secured within the hollow rotor shaft and extending upwardly therefrom for providing a structural connection between the hollow rotor shaft and said rotor hub; B. pivot means secured to said support means for interconnecting said support means and said rotor hub to permit both rotation and angular movement therebetween, whereby said rotor hub is configured as a floating hub; C. a flexible bellows circumscribing said support means and interconnecting the hollow rotor shaft and said rotor hub for directing the flow of air from within the hollow rotor shaft into said rotor hub to accommodate pivotal movement of said rotor hub without impeding the flow of air; D. sealed bearing means disposed intermediate said flexible bellows and said rotor hub for accommodating the rotational movement between said rotor hub and the hollow rotor shaft; E. porting means attached to said pivot means, said porting means being disposed within said rotor hub for distributing the flow of air from the hollow shaft and through said flexible bellows to the cavities within each of the rotor blades, said parting means including: i. an inlet port having a cross-sectional configuration equivalent to the cross-sectional configuration of the hollow rotor shaft; ii. an outlet port corresponding to each of the rotor blades and having a cross-sectional configuration equivalent to the cross-sectional configuration of the cavity within the respective rotor blades; and iii. a curved passageway interconnecting each of said outlet ports with said inlet port to minimize the pressure drop of the air flow through said porting means; F. connecting means disposed intermediate said rotor hub and each of the rotor blades for securing the rotor blades to said rotor hub, said connecting means being adapted to provide for both pivotal and rotational movement between said rotor hub and each of the rotor blades; and G. ducting means disposed intermediate each of said inlet ports and the cavity of the corresponding one of the rotor blades for conveying a flow of air from said porting means into the cavity within each rotor blade, whereby the flow of air is conveyed from the air pressure source within the body of the helicopter to each of the rotor blades while permitting rotational and angular movement between the hollow rotor shaft and the rotor blades.