Patent classifications
B64C27/78
Gimbaled tail rotor hub with spherical elastomeric centrifugal force bearing for blade retention and pitch change articulation
A rotor hub comprises a gimbal assembly and an elastomeric centrifugal force bearing. The gimbal assembly is configured to transfer rotational movement of a mast to the rotor hub and to enable the rotor hub to flap relative to the mast. The elastomeric centrifugal force bearing is configured to withstand centrifugal force of a rotor blade when the mast is rotated and is configured to accommodate pitch changes of the rotor blade. A method comprises designing a gimbal assembly that enables a tail rotor hub to flap relative to a tail rotor mast. A centrifugal force bearing is selected that enables tail rotor blades to withstand centrifugal force and that allows for tail rotor blade pitch change articulation. Then, instructions are provided to use the gimbal assembly and the centrifugal force bearing in an in-plane tail rotor assembly.
Gimbaled tail rotor hub with spherical elastomeric centrifugal force bearing for blade retention and pitch change articulation
A rotor hub comprises a gimbal assembly and an elastomeric centrifugal force bearing. The gimbal assembly is configured to transfer rotational movement of a mast to the rotor hub and to enable the rotor hub to flap relative to the mast. The elastomeric centrifugal force bearing is configured to withstand centrifugal force of a rotor blade when the mast is rotated and is configured to accommodate pitch changes of the rotor blade. A method comprises designing a gimbal assembly that enables a tail rotor hub to flap relative to a tail rotor mast. A centrifugal force bearing is selected that enables tail rotor blades to withstand centrifugal force and that allows for tail rotor blade pitch change articulation. Then, instructions are provided to use the gimbal assembly and the centrifugal force bearing in an in-plane tail rotor assembly.
Aircraft turbine engine comprising variable-pitch propeller blades
An assembly comprising a propeller blade and its system for angularly adjusting the pitch of the blade including a bowl which is radially delimited by an annular wall extending about an axis for adjusting the pitch of the blade, the bowl having a bottom wall, a free lower end of the root being fitted axially into a complementary housing of the bottom wall in order to rotatably connect the bowl and the blade about the pitch-adjustment axis. The root of the blade comprises a first limiting face that engages with a first abutment face of the bowl to limit the rotation of the blade in the event of breakage of the lower end of the root.
Aircraft turbine engine comprising variable-pitch propeller blades
An assembly comprising a propeller blade and its system for angularly adjusting the pitch of the blade including a bowl which is radially delimited by an annular wall extending about an axis for adjusting the pitch of the blade, the bowl having a bottom wall, a free lower end of the root being fitted axially into a complementary housing of the bottom wall in order to rotatably connect the bowl and the blade about the pitch-adjustment axis. The root of the blade comprises a first limiting face that engages with a first abutment face of the bowl to limit the rotation of the blade in the event of breakage of the lower end of the root.
System and method for tail rotor margin awareness
In an embodiment, a rotorcraft includes: tail rotor blades; a tail rotor actuator coupled to the tail rotor blades such that the pitch of the tail rotor blades varies according to a current extension of the tail rotor actuator; pilot flight controls electrically coupled to the tail rotor actuator; and a flight control computer electrically coupled to the tail rotor actuator and the pilot flight controls, the flight control computer configured to: determine the current extension of the tail rotor actuator; determine whether the current extension of the tail rotor actuator is within a margin of a maximum extension of the tail rotor actuator; and indicate a first warning to a pilot in response to the current extension of the tail rotor actuator being within the margin of the maximum extension of the tail rotor actuator.
Axial springs for rotor hub assembly
A rotor hub assembly for a rotorcraft includes a yoke forming a bearing bore. The yoke has a teetering axis extending through the bearing bore. The rotor hub assembly includes a flapping bearing disposed in the bearing bore. The flapping bearing is operable to regulate teetering of the yoke about the teetering axis. The rotor hub assembly includes an axial spring abutting the flapping, thereby reducing movement of the flapping bearing along the teetering axis.
Axial springs for rotor hub assembly
A rotor hub assembly for a rotorcraft includes a yoke forming a bearing bore. The yoke has a teetering axis extending through the bearing bore. The rotor hub assembly includes a flapping bearing disposed in the bearing bore. The flapping bearing is operable to regulate teetering of the yoke about the teetering axis. The rotor hub assembly includes an axial spring abutting the flapping, thereby reducing movement of the flapping bearing along the teetering axis.
Transmission unit of an anti-torque rotor for a helicopter
An anti-torque rotor includes a mast rotatable about a first axis; a plurality of blades extending along respective second axes; and a control element sliding along the first axis with respect to the mast, integrally rotatable with said mast, and connected to said blades. A control rod slides axially along first axis and is angularly fixed with respect to said first axis. A connection element is interposed between the control rod and the control element and is configured to enable the relative rotation of said control element with respect to the control rod about the first axis. A transmission unit is available in an active configuration or an inactive configuration. The transmission unit has an annular ridge axially and angularly integral with the control rod and a seat engaged by the ridge and angularly integral with the control element.
Transmission unit of an anti-torque rotor for a helicopter
An anti-torque rotor includes a mast rotatable about a first axis; a plurality of blades extending along respective second axes; and a control element sliding along the first axis with respect to the mast, integrally rotatable with said mast, and connected to said blades. A control rod slides axially along first axis and is angularly fixed with respect to said first axis. A connection element is interposed between the control rod and the control element and is configured to enable the relative rotation of said control element with respect to the control rod about the first axis. A transmission unit is available in an active configuration or an inactive configuration. The transmission unit has an annular ridge axially and angularly integral with the control rod and a seat engaged by the ridge and angularly integral with the control element.
Rotorcraft and associated rotor blade position monitoring system and method
A rotorcraft including a rotor hub, a pitch housing moveable relative to the rotor hub about at least a feather axis and a flap axis, the pitch housing defining an internal volume, a bearing pin, the inboard end portion of the bearing pin being fixedly connected to the rotor hub, wherein the bearing pin defines the feather axis, a spherical bearing connected to the inboard end portion of the pitch housing and defining the flap axis, wherein the bearing pin extends through the spherical bearing, a rotor blade connected to the outboard end portion of the pitch housing, and a sensor assembly positioned in the internal volume and operatively connected to both the pitch housing and the outboard end portion of the bearing pin.