Bell Helicopter Textron Inc.

Textron Innovations Inc.

Bell Textron Inc.

David E Heverly, Ii

Frank B Stamps

Michael Reaugh Smith

Taeoh Lee

Jeremy William DeWaters

Maurice D Griffin

Matthew Wade Hendricks

Robert J Pascal

James E Wright

Rupinder Singh

John Pappas

Michael Smith

Frank Bradley Stamps

Michael R Smith

A vibration control system for a rotor hub provides vibration attenuation in an aircraft by reducing the magnitude of rotor induced vibratory. The system can include a force generating device attached to a rotor hub which rotates along with the rotor at the rotational speed of the rotor. Vibratory shear force is generated by rotating unbalanced weights each about an axis non-concentric with the rotor hub axis at high speed to create large centrifugal forces. The rotational speed of the weights can be a multiple of the rotor rotational speed to create shear forces for canceling rotor induced vibrations. The amplitude of the generated shear force is controlled by indexing the positions of the unbalanced weights relative to each other, while the phase of the shear force is adjusted by equally phasing each weight relative to the rotor.

Active vibration control system with non-concentric revolving masses

In some examples, an oscillatory pumping system comprises: one or more active piston, a fluid, and two motors. The one or more active piston is disposed in a channel fluidically coupling two fluid chambers. The passive piston has a frequency response operable to counteract a vibratory displacement. The fluid is disposed in the channel and the two fluid chambers. The two motors couple to the one or more active piston. The two motors are operable to selectively change the frequency response of the passive piston based on oscillating the one or more active piston.

Oscillatory pumping system for liquid vibration isolator

A method and system to isolate vibrations, including a first pair of fluid chambers disposed to isolate first vibrations between a first body and a second body, wherein the first vibrations are parallel to a first axis, wherein the first body is a propeller hub, a rotor hub, a pylon attachment, or an engine, and wherein the second body is a propeller shaft, a rotor mast, or a body attachment; a second pair of fluid chambers disposed to isolate second vibrations between the first and second bodies, wherein the second vibrations are parallel to a second axis perpendicular to the first axis; first and second inertia tracks disposed to place the first and second pairs of chambers in fluid communication, respectively; and a plurality of elastic energy storage devices coupled to the first body and the second body and disposed to isolate vibrations between the first and second bodies.

Planar vibration isolator

A rotor system includes a hub assembly, a first, second, and third rotor blade rotatably attached to the hub assembly, a first, second, and third damper pivotally attached to the hub assembly and pivotally attached to the first, second, and third rotor blade, respectively, and a control system operably associated with the first, second, and third damper. A method to control vibratory forces exerted on the hub assembly via the first and second rotor blade includes separately controlling a dynamic spring rate of each of the first and second dampers with the control system.

Vibration control with active lag damper

In one embodiment, a centrifugal force generating device comprises a first hydraulic rotor, a second hydraulic rotor, and one or more hydraulic control valves. The first hydraulic rotor comprises a first mass and is configured to rotationally drive the first mass around a first axis of rotation using a first flow of hydraulic fluid through the first hydraulic rotor. The second hydraulic rotor comprises a second mass and is configured to rotationally drive the second mass around a second axis of rotation using a second flow of hydraulic fluid through the second hydraulic rotor. The one or more hydraulic control valves are configured to control the first flow of hydraulic fluid through the first hydraulic rotor and the second flow of hydraulic fluid through the second hydraulic rotor.

Hydraulic vibration control

The vibration suppression system includes a vibration isolator located in each corner in a four corner pylon mount structural assembly. The combination of four vibration isolators, two being forward of the transmission, and two being aft of the transmission, collectively are effective at isolating main rotor vertical shear, pitch moment, as well as roll moment induced vibrations. Each opposing pair of vibration isolators can efficiently react against the moment oscillations because the moment can be decomposed into two antagonistic vertical oscillations at each vibration isolator. A pylon structure extends between a pair of vibration isolators thereby allowing the vibration isolators to be spaced a away from a vibrating body to provide increased control.

Rotorcraft vibration suppression system in a four corner pylon mount configuration

An oscillating pump system includes a pump operable to circulate a fluid. The pump has a first port stage including an inlet port and an outlet port and a second port stage including a first oscillating port and a second oscillating port. An oscillator disk is disposed between the first port stage and the second port stage. The oscillator disk is rotatable relative to the inlet port, the outlet port, the first oscillating port and the second oscillating port. During rotation, the oscillator disk alternatingly routes the fluid to the inlet port from the first and second oscillating ports and alternatingly routes the fluid from the outlet port to the first and second oscillating ports, thereby generating oscillating fluid flow.

Oscillating pump systems for use on aircraft

A vibration isolation system includes a vibration isolator configured to flow a fluid. A fluid pumping system is connected to the vibration isolator. The fluid pumping system includes a fluid flow pathway configured to flow the fluid to the vibration isolator. The fluid pumping system includes a piston assembly positioned in the fluid flow pathway. The piston assembly includes a first piston and a second piston configured to displace the fluid in opposite directions through the fluid flow pathway. The vibration isolation system includes a fluid flow augmentation system, which includes an eccentric member positioned between the first piston and the second piston. The fluid flow augmentation system is configured to control a flow of the fluid to the vibration isolator through the fluid flow pathway by controlling a displacement of the first piston and the second piston through at least a partial rotation of the eccentric member.

Controlled pump augmentation for active vibration isolation

A tunable vibration isolator with active tuning elements having a housing, fluid chamber, and at least one tuning port. A piston is resiliently disposed within the housing. A vibration isolation fluid is disposed within the fluid chambers and the tuning ports. The tunable vibration isolator may employ either a solid tuning mass approach or a liquid tuning mass approach. The active vibration elements are preferably solid-state actuators.

Piezoelectric liquid inertia vibration eliminator

A method of isolating vibrations between vibrating bodies includes determining a pressure differential between a first fluid chamber and a second fluid chamber of a liquid inertia vibration eliminator (LIVE) unit, and selectively injecting fluid into or withdrawing fluid from the LIVE unit based on the pressure differential. A system for isolating vibrations between bodies includes a vibration isolator including fluid, a fluid regulator valve in fluid communication with the vibration isolator to selectively flow fluid through the vibration isolator, a pressurized fluid source in fluid communication with the fluid regulator to supply fluid to the fluid regulator, a controller in signal communication with the fluid regulator to control fluid flow between the fluid regulation valve and the vibration isolator, and at least one sensor in signal communication with the controller.

Active vibration isolation with direct fluid actuation

A rotorcraft vibration isolation system includes a plurality of liquid inertia vibration elimination (LIVE) units mounted on a first rotorcraft surface, an accumulator mounted on a second rotorcraft surface at a location that is remote from locations of the plurality of LIVE units, and a fluid passage to connect the accumulator to the plurality of LIVE units in parallel. The fluid passage has sufficient length to traverse between the location of the accumulator and each location of each LIVE unit. During rotorcraft operation, the second rotorcraft surface experiences lesser periodic vibration than the first rotorcraft surface.

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Arlington, TX, United States of America

David E Heverly, Ii